RESOURCES AND WORKING DRAFTS ONLY

Devil worm

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Human impact on marine ecosystems

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Synergies amongst anthropogenic impacts on deep-sea habitats: The lines link impacts that, when found together, have a synergistic effect on habitats or faunal communities. The lines are colour coded, indicating the direction of the synergy. LLRW, low-level radioactive waste; CFCs, chlorofluorocarbons; PAHs, polycyclic aromatic hydrocarbons.[1]
Model results for global count density in four size classes. Model prediction of global count density (pieces km−2; see colorbar) for each of four size classes (0.33–1.00 mm, 1.01–4.75 mm, 4.76–200 mm, and >200 mm).[2]
Model results for global weight density in four size classes.Model prediction of global weight density (g km−2; see colorbar) for each of four size classes (0.33–1.00 mm, 1.01–4.75 mm, 4.76–200 mm, and >200 mm). The majority of global weight is from the largest size class.[2]
Litter composition in different physiographic settings across European waters.[3]
Spatial patterns for (A) species richness, (B) range rarity, and (C) proportional range rarity and (D) cumulative human impacts within EEZs and ABNJ.The highest values for all diversity measures within 5% of EEZ or ANBJ area are also shown. Due to scale, not all values may be visible. EEZ boundaries are shown in white.[4]
Response to global change in marine and terrestrial biodiversity.[5]
History
Shifting baselines
Ecosystem services
Ecosystem disruption
Overexploitation
Habitat destruction
Acidification
Death By Plastic
Shipping noise
Links to land ecosystems
Biodiversity and species extinction
Future

"Habitat destruction is one of five global ecological pressures affecting the ocean, along with fishing pressure, climate change (including ocean acidification, water pollution and the introduction of alien species or genotypes."[6]

Biocapacity:

Marine Habitat destruction [2]

"Our use of natural resources has grown dramatically, particularly since the mid-20th century, so that we are endangering the key environmental systems that we rely upon."[14]

ocean acidification and ocean warming

- makes it more difficult for shellfish to make their shells, killing coral (now in the "third mass bleaching event". On present projections, coral reefs will cease to exist by 2050. They will be replaced with slime. Coral reefs support 500 million people world wide.

  • Marine food chains at risk of collapse, extensive study of world's oceans finds The Guardian, 13 October 2015.
  • Nagelkerken, I. and Connell, S.D. (2015) "Global alteration of ocean ecosystem functioning due to increasing human CO2 emissions". Proceedings of the National Academy of Sciences, 112 (43): 13272–13277. doi:10.1073/pnas.1510856112

Todays ocean is 30% more acidic than it was before the industrial revolution.[15]

From Habitat destruction... "Wetlands and marine areas have endured high levels of habitat destruction. More than 50% of wetlands in the U.S. have been destroyed in just the last 200 years.[16] Between 60% and 70% of European wetlands have been completely destroyed.[17] About one-fifth (20%) of marine coastal areas have been highly modified by humans.[18] One-fifth of coral reefs have also been destroyed, and another fifth has been severely degraded by overfishing, pollution, and invasive species; 90% of the Philippines’ coral reefs alone have been destroyed.[19] Finally, over 35% mangrove ecosystems worldwide have been destroyed.[19]"

consequences and denial

We looked at the oceans and thought they would last forever... Oceans are finite. They cannot indefinitely absorb pollution or survive unrelieved overexploitation.

"threats to the ocean"

"collapse of the oceans"

We have to decarbonise the oceans or face the consequences.

It's not just marine life that is at risk... humans will suffer too.

Living dangerously[20]

Denial mechanisms

It has taken 4.5 billion years for within decades we have undermined the very basis on which life exists. The biggest problem is ignorance. - Sylvia Earle

protection

Only 4% of the ocean is protected. But protection cannot stop the oceans from acidifying and warming.

"Natural capital is defined as the stock of environmental assets such as soil, biodiversity and freshwater which generate bene ts to humans."

"For every pound of tuna we fish from of the ocean, we are now putting back two pounds of plastic. This is a transfer ratio that we cannot continue to sustain." — UCSB marine scientist Douglas McCauley

"scientists propose that, as a result of human activity, we have transitioned from the Holocene into a new geological epoch: the Anthropocene."

"BIODIVERSITY: The Living Planet Index, which measures biodiversity abundance levels based on 14,152 monitored populations of 3,706 vertebrate species, shows a persistent downward trend."

"Earth’s ecosystems have evolved for millions of years. This process has resulted in diverse and complex biological communities, living in balance with their environment. These diverse ecosystems also provide people with food, fresh water, clean air, energy, medicine and recreation. Over the past 100 years, however, nature and the services it provides to humanity have come under increasing risk. The size and scale of the human enterprise have grown exponentially since the mid-20th century. As a result, the environmental conditions that fostered this extraordinary growth are beginning to shift. To symbolize this emerging environmental condition, Nobel Prize winner Paul Crutzen (2002) and others have proposed that we have transitioned from the Holocene into a new geological epoch, calling it the “Anthropocene” (e.g. Waters et al., 2016). During the Anthropocene, our climate has changed more rapidly, oceans are acidifying and entire biomes are disappearing – all at a rate measurable during a single human lifetime. This trajectory constitutes a risk that the Earth will become much less hospitable to our modern globalized society (Richardson et al., 2011). Scientists are now trying to discern which human-induced changes represent the greatest threat to our planet’s resilience (Rockström et al., 2009a). Such is the magnitude of our impact on the planet that the Anthropocene might be characterized by the world’s sixth mass extinction event. In the past such extinction events took place over hundreds of thousands to millions of years. What makes the Anthropocene so remarkable is that these changes are occurring within an extremely condensed period of time. Furthermore, the driving force behind the transition is exceptional. This is the first time a new geological epoch may be marked by what a single species (Homo sapiens) has consciously done to the planet – as opposed to what the planet has imposed on resident species."[14]


"Recent human development has taken place within the relatively stable climatic conditions of the Holocene epoch (Figure 1). The concept of a new epoch – the Anthropocene – is attracting the attention of more and more scientists with a wide range of interests and expertise. Geologists interpret the Earth’s environmental phases, including the history of climate, atmosphere and biodiversity, by studying what is recorded in the rock record. Eons, eras, periods and epochs are based on progressively smaller but nested units of geologic time. They are defined through global events that leave a trace within rock strata. For instance, there might be evidence of changes in rock chemistry or of the emergence or disappearance of particular species identified through their fossilized remains. Until recently all of these phase or time changes resulted from naturally occurring events such as meteorite impacts, tectonic movements, massive volcanic activity and changes in atmospheric conditions. Sometimes the effects of these changes on contemporary species were so profound as to cause widespread mass extinctions. To date, five mass extinctions have been identified in the rock record, including at the end of the Permian period when over 90 per cent of marine and around 70 per cent of terrestrial species were lost (e.g. Erwin, 1994). How might a future geologist identify the Anthropocene epoch in the rock record? There are many features that might bear witness to human influence. For example, remains of some megacities may become complex fossil structures. Urbanization itself may be regarded as an alteration in sedimentation processes via the construction of manmade rock strata. Scientists suggest a range of potential markers will be detected, from pesticides to nitrogen and phosphorus, and radionuclides (Waters et al., 2016). The accumulation of particulate plastics in marine sediments (Zalasiewicz et al., 2016) might be found in many of the rocks. Finally, it is likely that a future geologist will notice the rapid decline in the number of species based on clues in the fossil record (Ceballos et al., 2015): we are already losing species at a rate consistent with a sixth mass extinction event. The current evidence regarding these types of changes indicates that the Anthropocene may have commenced in the mid-20th Century (Waters et al., 2016)"[14]

"Marine ecosystems provide a wide variety of services, including provision of food, regulation of climate, support via primary production and nutrient recycling, and cultural enrichment.[21] However, many coastal and shelf ecosystems are currently degraded from their earlier states,[22][23][24][25] which compromises the services they can provide. One of the fundamental challenges in marine ecology is to relate the nature and magnitude of ecosystem services to the extent of habitats and communities, the biodiversity that they contain, and the types and levels of disturbance they can endure, because humans will continue to both use and depend on the marine environment."[26] – Ellis, S.L., Incze, L.S., Lawton, P., Ojaveer, H., MacKenzie, B.R., Pitcher, C.R., Shirley, T.C., Eero, M., Tunnell Jr, J.W., Doherty, P.J. and Zeller, B.M. (2011) "Four regional marine biodiversity studies: approaches and contributions to ecosystem-based management". PloS one, 6 (4): e18997. doi:10.1371/journal.pone.0018997

"human Influence"|"human Influences"|"human impact"|"human impacts" on "marine ecosystems"


  • Jennings, S. and Kaiser, M.J., 1998. The effects of fishing on marine ecosystems. Advances in marine biology, 34, pp. 201–352.
  • Myers, R.A. and Worm, B., 2003. Rapid worldwide depletion of predatory fish communities. Nature, 423(6937), pp. 280–283.
  • Waycott, M., Duarte, C.M., Carruthers, T.J., Orth, R.J., Dennison, W.C., Olyarnik, S., Calladine, A., Fourqurean, J.W., Heck, K.L., Hughes, A.R. and Kendrick, G.A., 2009. Accelerating loss of seagrasses across the globe threatens coastal ecosystems. Proceedings of the National Academy of Sciences, 106(30), pp. 12377–12381.
  • Worm, B., Barbier, E.B., Beaumont, N., Duffy, J.E., Folke, C., Halpern, B.S., Jackson, J.B., Lotze, H.K., Micheli, F., Palumbi, S.R. and Sala, E., 2006. Impacts of biodiversity loss on ocean ecosystem services. science, 314(5800), pp. 787–790.
  • Myers, R.A. and Worm, B., 2003. Rapid worldwide depletion of predatory fish communities. Nature, 423(6937), pp. 280–283.
  • Hughes, T.P., Baird, A.H., Bellwood, D.R., Card, M., Connolly, S.R., Folke, C., Grosberg, R., Hoegh-Guldberg, O., Jackson, J.B.C., Kleypas, J. and Lough, J.M., 2003. Climate change, human impacts, and the resilience of coral reefs. science, 301(5635), pp. 929–933.
  • Halpern, B.S., Walbridge, S., Selkoe, K.A., Kappel, C.V., Micheli, F., D'Agrosa, C., Bruno, J.F., Casey, K.S., Ebert, C., Fox, H.E. and Fujita, R., 2008. A global map of human impact on marine ecosystems. Science, 319(5865), pp. 948–952.
  • Pauly, D., Christensen, V., Guénette, S., Pitcher, T.J., Sumaila, U.R., Walters, C.J., Watson, R. and Zeller, D., 2002. Towards sustainability in world fisheries. Nature, 418(6898), pp. 689–695.
  • Bellwood, D.R., Hughes, T.P., Folke, C. and Nyström, M., 2004. Confronting the coral reef crisis. Nature, 429(6994), pp. 827–833.
  • Barbier, E.B., Hacker, S.D., Kennedy, C., Koch, E.W., Stier, A.C. and Silliman, B.R., 2011. The value of estuarine and coastal ecosystem services. Ecological monographs, 81(2), pp. 169–193.
  • Doney, S.C., Ruckelshaus, M., Duffy, J.E., Barry, J.P., Chan, F., English, C.A., Galindo, H.M., Grebmeier, J.M., Hollowed, A.B., Knowlton, N. and Polovina, J., 2012. Climate change impacts on marine ecosystems. Marine Science, 4.
  • Fourqurean, J.W., Duarte, C.M., Kennedy, H., Marbà, N., Holmer, M., Mateo, M.A., Apostolaki, E.T., Kendrick, G.A., Krause-Jensen, D., McGlathery, K.J. and Serrano, O., 2012. Seagrass ecosystems as a globally significant carbon stock. Nature Geoscience, 5(7), pp. 505–509.
  • Short, F.T., Polidoro, B., Livingstone, S.R., Carpenter, K.E., Bandeira, S., Bujang, J.S., Calumpong, H.P., Carruthers, T.J., Coles, R.G., Dennison, W.C. and Erftemeijer, P.L., 2011. Extinction risk assessment of the world’s seagrass species. Biological Conservation, 144(7), pp. 1961–1971.
  • Short, F.T., Polidoro, B., Livingstone, S.R., Carpenter, K.E., Bandeira, S., Bujang, J.S., Calumpong, H.P., Carruthers, T.J., Coles, R.G., Dennison, W.C. and Erftemeijer, P.L., 2011. Extinction risk assessment of the world’s seagrass species. Biological Conservation, 144(7), pp. 1961–1971.
  • Harnik, P.G., Lotze, H.K., Anderson, S.C., Finkel, Z.V., Finnegan, S., Lindberg, D.R., Liow, L.H., Lockwood, R., McClain, C.R., McGuire, J.L. and O’Dea, A., 2012. Extinctions in ancient and modern seas. Trends in Ecology & Evolution, 27(11), pp. 608–617.
  • Kendrick, G.A., Waycott, M., Carruthers, T.J., Cambridge, M.L., Hovey, R., Krauss, S.L., Lavery, P.S., Les, D.H., Lowe, R.J., i Vidal, O.M. and Ooi, J.L., 2012. The central role of dispersal in the maintenance and persistence of seagrass populations. BioScience, 62(1), pp. 56–65.
  • Costanza, R., d'Arge, R., De Groot, R., Faber, S., Grasso, M., Hannon, B., Limburg, K., Naeem, S., O'neill, R.V., Paruelo, J. and Raskin, R.G., 1997. The value of the world's ecosystem services and natural capital.
  • Assessment, M.E., 2003. Ecosystems and human well-being (Vol. 200). Washington, DC: Island Press.
Degradation of marine habitats
The collapse of Atlantic cod off the coast of Newfoundland in 1992 as a result of overfishing. The population never recovered, completely altering the ecosystem and rendering the species locally extinct.

from Holocene extinction...

"Rising levels of carbon dioxide are resulting in influx of this gas into the ocean, increasing its acidity. Marine organisms which possess Calcium Carbonate shells or exoskeletons experience physiological pressure as the carbonate reacts with acid. This is already resulting in coral bleaching on various coral reefs worldwide, which provide valuable habitat for very high biodiversity. Marine gastropods, bivalves and other invertebrates are also affected, as are any organisms that feed on them. Fishing has had a devastating effect on marine organism populations for several centuries even before the explosion of destructive and highly effective fishing practices like trawling.[27] Humans are unique among predators in that they regularly predate on other adult apex predators, particularly in marine environments;[28] bluefin tuna, blue whales, and various sharks in particular are particularly vulnerable to predation pressure from human fishing. A 2016 study published in Science concludes that humans tend to hunt larger species, and this could disrupt ocean ecosystems for millions of years.[29] Jonathan Payne, associate professor and chair of geological sciences at Stanford University, explains: "If this pattern goes unchecked, the future oceans would lack many of the largest species in today’s oceans. Many large species play critical roles in ecosystems and so their extinctions could lead to ecological cascades that would influence the structure and function of future ecosystems beyond the simple fact of losing those species."[30]

Marine habitat destruction

"Habitat destruction occurs when the conditions necessary for plants and animals to survive are significantly compromised or eliminated. Most areas of the world's oceans are experiencing habitat loss. But coastal areas, with their closeness to human population centers, have suffered disproportionately and mainly from manmade stresses. Habitat loss here has far-reaching impacts on the entire ocean's biodiversity. These critical areas, which include estuaries, swamps, marshes, and wetlands, serve as breeding grounds or nurseries for nearly all marine species."Cite error: A <ref> tag is missing the closing </ref> (see the help page).

"Jackson rated the status of ocean ecosystems.

  • Coral reefs: “Critically endangered” and among the most threatened ecosystems
  • Estuaries and coastal seas: “Critically endangered,” threatened by overfishing and runoff
  • Continental shelves: “Endangered” due to, among other things, losses of fishes and sharks
  • Open ocean: “Threatened” mainly by overfishing...

Overexploitation, pollution, and climate are the three main “drivers” that must be addressed, Jackson said... Jackson says in his paper that the following steps, if taken immediately, could reverse the demise of the oceans: Establish marine reserves, enforce fishing regulations, implement aquaculture, remove subsidies on fertilizer use, muster human ingenuity to limit fossil fuel consumption, buy time by establishing local conservation measures."[31][32]

coastal

"Every day 1,500 new homes rise along the U.S. coastline. More than half the nation's population now lives in coastal counties, which amount to only 17 percent of the land in the lower 48. In 2003 coastal watersheds generated over six trillion dollars, more than half the national economy, making them among our most valuable assets. Yet two blue-ribbon bipartisan panels—the Pew Oceans Commission and the U.S. Commission on Ocean Policy, convened by the Pew Trusts and the U.S. Congress, respectively—recently issued disturbing reports that found the coasts are being battered by an array of pollution and population pressures. Former Secretary of Energy Adm. James D. Watkins—not exactly a wild-eyed environmentalist—chaired the U.S. commission and laid it out for Congress: "Our failure to properly manage the human activities that affect the nation's oceans, coasts, and Great Lakes is compromising their ecological integrity…threatening human health, and putting our future at risk."[33] <= plus six more pages


"The Adélies are the canaries in the coal mine of climate change in the Antarctic," according to [34] <= plus four more pages

"today, for the first time, humanity's global civilization—the worldwide, increasingly interconnected, highly technological society in which we all are to one degree or another, embedded—is threatened with collapse by an array of environmental problems... The human predicament is driven by overpopulation, overconsumption of natural resources and the use of unnecessarily environmentally damaging technologies and socio-economic-political arrangements to service Homo sapiens’ aggregate consumption".[35]


  • Oceans on the Brink: Dying Plankton, Dead Zones, Acidification 31 July 2010.
  • The coming death of the oceans
  • Worm, B., Barbier, E.B., Beaumont, N., Duffy, J.E., Folke, C., Halpern, B.S., Jackson, J.B., Lotze, H.K., Micheli, F., Palumbi, S.R. and Sala, E. (2006) "Impacts of biodiversity loss on ocean ecosystem services". Science, 314 (5800): 787–790. Cited by 2960
  • Halpern, B.S., Walbridge, S., Selkoe, K.A., Kappel, C.V., Micheli, F., D'Agrosa, C., Bruno, J.F., Casey, K.S., Ebert, C., Fox, H.E. and Fujita, R. (2008) "A global map of human impact on marine ecosystems". Science, 319 (5865): 948–952. Cited by 2727
  • Harvell, C.D., Mitchell, C.E., Ward, J.R., Altizer, S., Dobson, A.P., Ostfeld, R.S. and Samuel, M.D. (2002) "Climate warming and disease risks for terrestrial and marine biota". Science, 296 (5576): 2158–2162. Cited by 1769 pdf
  • Lotze, H.K., Lenihan, H.S., Bourque, B.J., Bradbury, R.H., Cooke, R.G., Kay, M.C., Kidwell, S.M., Kirby, M.X., Peterson, C.H. and Jackson, J.B. (2006) "epletion, degradation, and recovery potential of estuaries and coastal seas". Science, 312 (5781): 1806–1809. pdf
  • Orth, R.J., Carruthers, T.J., Dennison, W.C., Duarte, C.M., Fourqurean, J.W., Heck, K.L., Hughes, A.R., Kendrick, G.A., Kenworthy, W.J., Olyarnik, S. and Short, F.T. (2006) "A global crisis for seagrass ecosystems". Bioscience, 56 (12): 987–996. doi:10.1641/0006-3568(2006)56[987:AGCFSE2.0.CO;2]
  • Waycott, M., Duarte, C.M., Carruthers, T.J., Orth, R.J., Dennison, W.C., Olyarnik, S., Calladine, A., Fourqurean, J.W., Heck, K.L., Hughes, A.R. and Kendrick, G.A. (2009) "Accelerating loss of seagrasses across the globe threatens coastal ecosystems". Proceedings of the National Academy of Sciences, 106 (30),: 12377–12381. pdf
  • Lester, S.E., Halpern, B.S., Grorud-Colvert, K., Lubchenco, J., Ruttenberg, B.I., Gaines, S.D., Airamé, S. and Warner, R.R., 2009. Biological effects within no-take marine reserves: a global synthesis. Marine Ecology Progress Series, 384, pp. 33–46. pdf
  • Crain, C.M., Kroeker, K. and Halpern, B.S., 2008. Interactive and cumulative effects of multiple human stressors in marine systems. Ecology letters, 11(12), pp. 1304–1315. pdf
  • Defeo, O., McLachlan, A., Schoeman, D.S., Schlacher, T.A., Dugan, J., Jones, A., Lastra, M. and Scapini, F., 2009. Threats to sandy beach ecosystems: a review. Estuarine, Coastal and Shelf Science, 81(1), pp. 1–12. pdf
  • Belkin, I.M., 2009. Rapid warming of large marine ecosystems. Progress in Oceanography, 81(1), pp. 207–213.
  • Tittensor, D.P., Mora, C., Jetz, W., Lotze, H.K., Ricard, D., Berghe, E.V. and Worm, B., 2010. Global patterns and predictors of marine biodiversity across taxa. Nature, 466(7310), pp. 1098–1101.
  • Rabalais, N.N., Turner, R.E., Díaz, R.J. and Justić, D., 2009. Global change and eutrophication of coastal waters. ICES Journal of Marine Science: Journal du Conseil, 66(7), pp. 1528–1537.
  • Gattuso, J.P., Magnan, A., Billé, R., Cheung, W.W.L., Howes, E.L., Joos, F., Allemand, D., Bopp, L., Cooley, S.R., Eakin, C.M. and Hoegh-Guldberg, O., 2015. Contrasting futures for ocean and society from different anthropogenic CO2 emissions scenarios. Science, 349(6243), p.aac4722. pdf
  • Cheung, W.W., Watson, R. and Pauly, D., 2013. Signature of ocean warming in global fisheries catch. Nature, 497(7449), pp. 365–368. pdf
  • Danovaro, R., Corinaldesi, C., Dell'Anno, A., Fuhrman, J.A., Middelburg, J.J., Noble, R.T. and Suttle, C.A. (2011) "Marine viruses and global climate change". FEMS microbiology reviews, 35 (6): 993–1034.doi:10.1111/j.1574-6976.2010.00258.x 993-1034 [
  • Pörtner, H.O., Karl, D.M., Boyd, P.W., Cheung, W., Lluch-Cota, S.E., Nojiri, Y., Schmidt, D.N., Zavialov, P.O., Alheit, J., Aristegui, J. and Armstrong, C., 2014. Ocean systems. Climate change 2014: impacts, adaptation, and vulnerability. Part A: global and sectoral aspects. contribution of working group II to the fifth assessment report of the intergovernmental panel on climate change, pp. 411–484. pdf

See also

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References

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  34. ^ Signs From Earth: No Room to Run National Geographic.
  35. ^ Ehrlich, P.R. and Ehrlich, A.H., 2013, March. Can a collapse of global civilization be avoided?. In Proc. R. Soc. B (Vol. 280, No. 1754, p. 20122845). The Royal Society.

Biological information system

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Marine life

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Spinosaurus restoration based on a 2014 description

Timeline

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See {{Graphical timeline}}

References

  1. ^ Parry, S.F.; Noble S.R.; Crowley Q.G.; Wellman C.H. (2011). "A high-precision U–Pb age constraint on the Rhynie Chert Konservat-Lagerstätte: time scale and other implications". Journal of the Geological Society. 168 (4). London: Geological Society: 863–872. doi:10.1144/0016-76492010-043.
  2. ^ Kaufmann, B.; Trapp, E.; Mezger, K. (2004). "The numerical age of the Upper Frasnian (Upper Devonian) Kellwasser horizons: A new U-Pb zircon date from Steinbruch Schmidt(Kellerwald, Germany)". The Journal of Geology. 112 (4): 495–501. Bibcode:2004JG....112..495K. doi:10.1086/421077.




Classification

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"The science of taxonomy classifies species into evolutionary relationships to help identify organisms and name species. Taxonomy is also referred to as scientific classification. Today's classification system was developed by Carl Linnaeus external link as an important tool for use in the study of biology and for use in the protection of biodiversity. Without very specific classification information and a naming system to identify species' relationships, scientists would be limited in attempts to accurately describe the relationships among species. Understanding these relationships helps predict how ecosystems can be altered by human or natural factors. Preserving biodiversity is facilitated by taxonomy. Species data can be better analyzed to determine the number of different species in a community and to determine how they might be affected by environmental stresses. Family, or phylogenetic, trees for species help predict environmental impacts on individual species and their relatives."[1]

"Linnaean Taxonomic System: Carl Linnaeus was born in 1707 and died in 1778. He created the entire category of systematic zoology and botany as well as a classification scheme—still used by biologists today. His masterpiece was the Systema Naturae. Linnaeus invented the classification system to establish consensus on plant and animal names and to understand complex evolutionary relationships between organisms. The Linnaean taxonomic system begins with the most general category of Domain or Kingdom and becomes increasingly specific until it ends with a specific genus and species name derived from Greek and/or Latin roots. Based on concepts introduced by his scientist predecessors, Linnaeus developed his system so that each species had a Latin double name. The first name is the genus and the second is the species name. This two-word naming system is called binomial nomenclature. The name is always italicized with the genus capitalized and the species in lowercase letters."[1]

The World Register of Marine Species

As of November 20, 2010: 205,968 valid species; of which 173,404 are checked (84%) 331,305 species names including synonyms 405,601 taxa (infraspecies to kingdoms)

"The aim of a World Register of Marine Species (WoRMS) external link is to provide an authoritative and comprehensive list of names of marine organisms, including information on synonymy. While highest priority goes to valid names, other names in use are included so that this register can serve as a guide to interpret taxonomic literature. The content of WoRMS is controlled by taxonomic experts, not by database managers. WoRMS has an editorial management system where each taxonomic group is represented by an expert who has the authority over the content, and is responsible to control the quality of the information. Each of these main taxonomic editors can invite several specialists of smaller groups within their area of responsibility."[1]

"This register of marine species grew from the European Register of Marine Species (ERMS external link), and its combination with several other species registers maintained at the Flanders Marine Institute (VLIZ external link). Rather than building separate registers for all projects, and to make sure taxonomy used in these different projects is consistent, we developed a consolidated database called ‘Aphia'. A list of marine species registers included in Aphia is available below. MarineSpecies.org is the web interface to this database. The WoRMS is an idea that is being developed, and will combine information from Aphia with other authoritative marine species lists which are maintained by others (e.g. AlgaeBase, FishBase, Hexacorallia, NeMys)."[1]

Marine biology history

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"It wasn't until the writings of Aristotle external link from 384-322 BC that specific references to marine life were recorded. Aristotle identified a variety of species including crustaceans, echinoderms, mollusks, and fish. He also recognized that cetaceans are mammals, and that marine vertebrates are either oviparous (producing eggs that hatch outside the body) or viviparous (producing eggs that hatch within the body). Because he is the first to record observations on marine life, Aristotle is often referred to as the father of marine biology."[2]

"The modern day study of marine biology began with the exploration by Captain James Cook external link (1728-1779) in 18th century Britain. Captain Cook is most known for his extensive voyages of discovery for the British Navy, mapping much of the world's uncharted waters during that time. He circumnavigated the world twice during his lifetime, during which he logged descriptions of numerous plants and animals then unknown to most of mankind. Following Cook's explorations, a number of scientists began a closer study of marine life including Charles Darwin external link (1809-1882) who, although he is best known for the Theory external link of Evolution external link, contributed significantly to the early study of marine biology. His expeditions as the resident naturalist aboard the HMS Beagle external link from 1831 to 1836 were spent collecting and studying specimens from a number of marine organisms that were sent to the British Museum for cataloguing. His interest in geology gave rise to his study of coral reefs and their formation. His experience on the HMS Beagle helped Darwin formulate his theories of natural selection and evolution based on the similarities he found in species specimens and fossils he discovered in the same geographic region."[2]

"The voyages of the HMS Beagle were followed by a 3-year voyage by the British ship HMS Challenger external link led by Sir Charles Wyville Thomson external link (1830-1882) to all the oceans of the world during which thousands of marine specimens were collected and analyzed. This voyage is often referred to as the birth of oceanography. The data collected during this trip filled 50 volumes and served as the basis for the study of marine biology across many disciplines for many years. Deep sea exploration was a benchmark of the Challenger's voyage disproving British explorer Edward Forbes' theory that marine life could not exist below about 550 m or 1,800 feet."[2]

"HMS Challenger was well equipped to explore deeper than previous expeditions with laboratories aboard stocked with tools and materials, microscopes, chemistry supplies, trawls and dredges, thermometers, devices to collect specimens from the deep sea, and miles of rope and hemp used to reach the ocean depths. The end product of the Challenger's voyage was almost 30,000 pages of oceanographic information compiled by a number of scientists from a wide range of disciplines. The "Report of the Scientific Results of the Exploring Voyage of H.M.S. Challenger during the years 1873-76" reported, in addition to the fact that life does exist below 550 m/1,800 feet, findings such as:"[2]

* 4,717 new species; * The first systematic plot of currents and temperatures in the ocean; * A map of bottom deposits much of which has remained current to the present; * An outline of the main contours of the ocean basins; and * The discovery of the mid-Atlantic Ridge external link.

"The report is an important work still used by scientists today. In addition to the report, Sir Thomson also wrote a book about the voyage in 1877 titled "The Voyage of the Challenger." He also wrote one of the early marine biology textbooks "The Depths of the Sea" in 1877."[2]

Marine ecology

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Marine trophics

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Reproduction

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Feeding methods

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Krill filter feeding

Locomotion

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Senescence

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Vision in fishes
The four-eyed fish feeds at the surface of the water with eyes that allow it to see both above and below the surface at the same time
The two stripe damselfish can signal secret alarms by reflecting ultraviolet to other fish of its species
The barreleye has barrel-shaped, telescopic eyes which are
generally directed upwards, but can also be swiveled forward
Flashlight fish use a retroreflector behind the retina with photophores to detect eyeshine in other fish

Mediaeval fish ponds

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The fish pond at the deserted mediaeval village of Wharram Percy
Fishing with nets, 15th century

5th century to the 15th century

Piscina: "in Roman times, an artificial reservoir used for swimming or as a fish pond. During the Middle Ages a piscina was a pool or tank in which fish were stored by monastic communities, for whose members fish was a staple item of diet. Although never a calculated feature of gardens, existing ponds or fish stews (tanks) were sometimes later incorporated in decorative schemes. At Monticello, Thomas Jefferson’s home near Charlottesville, Va., an original piscina has been restored. A stone vessel having a drain that leads directly to the ground, located near an altar of a church, and used for disposing of water from ablutions is also known as a piscina."[3]


  • "A significant part of Magna Carta is taken up with concerns about fish weirs."
  • "Many castles and manor houses (and monasteries) had nearby fish ponds. If a natural pond did not exist then one could be built."
  • Nash, Colin (2011) The History of Aquaculture p. 28–29, John Wiley and Sons. ISBN 9780813821634.

"When Britain was Catholic, meat was off the menu not only every Friday but for the 40 days of Lent and other holy days as well. Fish was considered a poor substitute (probably for good reason, in the days before refrigeration). With the dissolution of the monasteries in the 1530s, monastic fishponds disappeared along with the monks, and fish became politically suspect. Fish consumption did not recover for centuries."[4]

From Economy of England in the Middle Ages: "Fish ponds were created on most estates to provide freshwater fish for the consumption of the nobility and church; these ponds were extremely expensive to create and maintain."[5] "The use of expensive freshwater fish ponds on estates began to decline during this period (15th century), as more of the gentry and nobility opted to purchase freshwater fish from commercial river fisheries."[6]

During the Middle Ages, lampreys were widely eaten by the upper classes throughout Europe, especially during fasting periods, since their taste is much meatier than that of most true fish. King Henry I of England is said to have died from eating "a surfeit of lampreys".[7]

"Depending on their status in society and where they lived, medieval people had a variety of meats to enjoy. But thanks to Fridays, Lent, and various days deemed meatless by the Catholic Church, even the wealthiest and most powerful people did not eat meat or poultry every day. Fresh fish was fairly common, not only in coastal regions, but inland, where rivers and streams were still teeming with fish in the Middle Ages, and where most castles and manors included well-stocked fish ponds."[8]

  • "In the Middle Ages, the seas, lakes and rivers were teeming with fish, and medieval people took advantage of this fact with professional fishing fleets and fish traps. When a castle moat had water it might also have fish, and fish ponds were part of many manor holdings. Preserved fish was very common and easy to acquire." [8]
  • "Fish was allowed on the days of the week that the Church had declared "meatless" (such as every Friday and all of Lent), but it was usually eaten more often, especially in coastal regions. In medieval cookbooks, the exact type of fish wasn't always specified; as with measurements and cooking times, the knowledgeable cook decided what recipe went best with what fish."[8]
  • "Carp - Carp is native to northern European rivers and wasn't introduced into England until the late Middle Ages. Bream, a variety of carp, is indigenous to northern and central Europe and prefers slow-flowing and stagnant waters. This made it perfect for medieval fish ponds and castle moats, but its reputation as a bottom-feeder limited its prestige. The active dace, also of the carp family, could be caught by skilled anglers in fairly swift-moving streams and rivers, and occasionally made a good meal." [8]
  • "Lamprey and Eel - Lamprey fish are sometimes mistaken for eels because of their slick, snakelike appearance, but they are actually parasites that suck the blood of larger fish. They live in the sea and spawn in rivers. Eels spawn in the ocean and spend most of their lives in fresh water; they were often caught in river traps. Eels, which were very common in the Middle Ages, were sometimes carefully separated from their skins, seasoned, and returned to the skin for roasting. Some surviving medieval recipes regard lamprey and eel as interchangeable."[8]
  • "Pike - This carnivorous fish was held in high regard by medieval cooks and was a favorite of the nobility. Though often caught wild in the lakes and rivers of low-lying regions, pike were also kept in fish ponds, where they kept down the population of such prolific fish as bream."[8]

Monasteries

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"The demands of religion also dictated a prominent place for fish in the European diet, especially after the seventh century, when meat consumption was prohibited for observant Christians on approximately 150 fast days per year. Much of the fish supply must have come from fresh water or coastal salt water, because deep water fishing was not a significant activity until the later Middle Ages. Few data survive about fish consumption, but there bare scattered mentions of fish ponds in sources predating 1000."[9]

"In England, fish ponds are described in tenth-century charters, and the best documented case, the royal fish pond at Fosse, York, was constructed by William the Conqueror before 1086, supplying fish for the royal household and gifts for others until the thirteenth century. More sophisticated methods of farming fish began after the twelfth century with the development of sophisticated fish ponds, often linked with as system of pools by which supply could be tailored to fit the life cycle of the fish and to meet increased demands during Lent. Ingenious fish farmers also discovered that ponds could be drained every three to five years and planted with crops that benefited from the enriched soil, then grazed over by stock and ultimately returned for use as fish ponds in a regular rotation."[9]

"Large scale commercial fishing seems to have begun in the twelfth century, when herring became the quarry of English and German fishing fleets that ranged across the North and Baltic Seas. But it was not until the thirteenth century, when Lubek merchants booth financed Baltic fishing fleets and provided vast quantities of salt needed tom preserve the catch, that herring became the Lenten dish par excellence in northern Europe."[9] …and fishponds declined in importance…

Some cloister gardens contained small fish ponds as well, another source of food for the community.

Remains of monastery fishponds

Although Prittlewell Priory in Southend-on-Sea has long since gone, its fishponds at grid reference TQ 877 871 are still there and are popular with fisherpeople.

Castles and manor houses

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Fish House built at Meare for the chief fisherman of the Abbot of Glastonbury Abbey


Meat in Castles and Manor Homes

"A large portion of the foodstuffs served to the residents of castles and manor homes came from the land on which they lived. This included wild game from nearby forests and fields, meat and poultry from the livestock they raised in their pastureland and barnyards, and fish from stock ponds as well as from the rivers, streams and seas. Food was used swiftly -- usually within a few days, and sometimes on the same day -- and if there were leftovers, they were gathered up as alms for the poor and distributed daily."[8]

In the 14th century a Fish House was built at Meare for the chief fisherman of the Abbot of Glastonbury that was also used for salting and preparing fish.[10] It is the only surviving monastic fishery building in England.[11] At the time of the Dissolution in 1540, Meare Pool was said to contain a great abundance of pike, tench, roach and eels.[12] In 1638 it was owned by William Freake, who described it as "lately a fish pool".[13] The importance of this industry is illustrated by a series of acrimonious disputes between Glastonbury and the Dean and Chapter of Wells Cathedral.[14] The Abbey required fish on Fridays, fast days and during Lent. As many as 5000 eels were landed in a typical year.[15]

There were also three fishponds which would have allowed fish to have been bred or stored.[16]

  • Braybrooke – Braybrooke Castle - fortified manor house - mid C12 to early C16. "The earthwork and buried remains of the moated site, which measures 80m square, lie within a larger rectangular enclosure which is bounded by a ditch to the east, by a ditch and bank to the south and a pond to the west and north. These enclosure ditches form part of a water managment system associated with the moated manor and include ponds, fish breeding tanks and further water channels. To the north of the moated site is a large rectangular pond. At its eastern end is a smaller pond which is joined to the former by two channels which in turn form two sides of a small raised island. To the west of the moaed site are a series of inter-connencting fishponds that take the form of rectangular mounds surrounded by ditches. Three have shallow depressions or ponds within them which have been interpreted as fish-breeding tanks where small fish were kept until they were large enough to be transferred into the main pond."[5]
  • Raglan Castle - In the 15th century there were also extensive orchards and fish ponds surrounding the castle, favourably commented upon by contemporaries.[17] Upon inheriting Raglan in 1628, Henry Somerset, then the 5th Earl of Worcester, continued to live a grand lifestyle in the castle in the 1630s, with a host of staff, including a Master of Fishponds.[18]
  • Searle, Muriel V. (2002). West Country History: Somerset. Bristol: Venton Publications. ISBN 1-84150-802-0.


"Weoley Castle near Birmingham isn’t very noteworthy. No memorable lords dwelled there, no legendary battles surged against its walls, no knights rode out from its gates, across its moat, to defend the place—it has laid in ruins since at least the seventeenth century. But Weoley Castle’s toppled ramparts, empty moats, and relatively pedestrian history offers a glimpse of medieval fish farming. In 1902, the castle was the subject of an historical survey published by the Birmingham Archaeological Society; according to the survey’s author, the castle’s most striking feature was its several moats:"[19]

"There is a peculiar feature on the east side of the castle. The moat there was double, a narrow causeway separating the moat into two equal parts. As the east was the side of the castle least liable to attack, the object of the double moat is not apparent at first sight, but my own idea is that when moats were no longer of their former importance from a military point of view, they gained in importance from a culinary aspect, and that this division was to create a stew pond for my Lord the Pike and his Excellence the Carp, both persons of high distinction in medieval times."[19]

“Lord the Pike” and “his Excellence the Carp” are, of course, fish."[19]

"Medieval Europe was covered in castle moats and other manmade fish ponds—known as stew ponds—stocked with carp, pike, bream, perch, and other freshwater fish that were raised for the eventual journey to a nearby kitchen. Chaucer, the most famous of medieval documentarians, writes in his prologue to The Canterbury Tales that the Franklin (a non-noble landowner) had “many a breem and many a luce in stewe”—translated as “many bream and many pike in his fishpond.”"[19]

Remains of castle fishponds

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Remains of manor house fishponds

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  • Stew pond: Another name for fishponds during the mediaeval period.
  • Oakham Castle: Some deep hollows in the park are the remnants of the castle's dried-up stew ponds (fishponds).[20]

Villages

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Wharram Percy is a deserted medieval village (DMV) site on the western edge of the chalk Wolds in North Yorkshire, England. Wharram Percy is perhaps the best-known DMV in the whole of England, although there are several others which are in a similarly good state of preservation. Although the site has apparently been settled since pre-historic times, the village seems to have been most active from the tenth to the twelfth centuries. It is now in the care of English Heritage.[21] English Heritage. Retrieved 22 October 2011.

See also

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Notes

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  1. ^ a b c d The Naming of Life: Marine Taxonomy MarineBio.org. Updated 26 November 2010. Retrieved 3 May 2011.
  2. ^ a b c d e A History of the Study of Marine Biology MarineBio.org. Updated 26 November 2010. Retrieved 3 May 2011.
  3. ^ piscina (2012) In Encyclopædia Britannica. Retrieved 18 March 2012.
  4. ^ Feast and famine The Economist, 22 Nov 2007.
  5. ^ Dyer 2000, p. 102.
  6. ^ Dyer 2000, p. 107.
  7. ^ "A Surfeit of Lampreys". Time. 1955-05-09. Retrieved 2008-06-07.
  8. ^ a b c d e f g Types of Fish & Seafood: Water creatures eaten in medieval times About.com.
  9. ^ a b c Hunt ES and Murray JM (1999) The history of business in medieval Europe, 1200–1550 p. 17–18, Cambridge University Press. ISBN 0521495814.
  10. ^ "The Abbot's Fish House". Images of England. English Heritage. Retrieved 3 November 2008.
  11. ^ "Meare Fish House". English Heritage website. Retrieved 3 November 2008.
  12. ^ Bulleid, L.R.C.P., F.S.A.,, Arthur (1948/53/66). The Meare Lake Village. Taunton: pub. privately. pp. 1–14. {{cite book}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)CS1 maint: extra punctuation (link) CS1 maint: multiple names: authors list (link)
  13. ^ Havinden, Michael (1982). The Somerset Landscape. The making of the English landscape. London: Hodder and Stoughton. pp. 161–162. ISBN 0340201169.
  14. ^ Rippon, Stephen (2004). "Making the Most of a Bad Situation? Glastonbury Abbey, Meare, and the Medieval Exploitation of Wetland Resources in the Somerset Levels" (PDF). Medieval Archaeology. 40. Maney Publishing: 91–130. doi:10.1179/007660904225022816.
  15. ^ Searle p.100
  16. ^ Rippon, Stephen. "Making the Most of a Bad Situation? Glastonbury Abbey, Meare, and the Medieval Exploitation of Wetland Resources in the Somerset Levels" (PDF). archaeologydataservice.ac.uk. pp. 32–33. Retrieved 2008-11-04.
  17. ^ Kenyon (2003), p.11.
  18. ^ Tribe, p.1.
  19. ^ a b c d The Mastery of Fish Lapham's Quarterly, 6 November 2011.
  20. ^ "Oakham Castle". Rutland On Line. Retrieved 2007-02-20.
  21. ^ Wharram Percy

References

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Further reading

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by Melitta Weiss Adamson

  • Food and Eating in Medieval Europe

edited by Martha Carlin and Joel T. Rosenthal

  • Food in Medieval England: Diet and Nutrition

edited by by C.M. Woolgar, D. Serjeantson and T. Waldron

  • The Cambridge economic history of Europe, Volume 5

edited by E.E. Rich and C.H. Wilson

  • Food in the Middle Ages: A Book of Essays

by Melitta Weiss Adamson

  • Hoffmann, Richard C (1995) [ "Environmental change and the culture of common carp in medieval Europe"] Guelph Ichthyol. Rev. 3 : 57–85. (blacklisted!?)
  • Currie, CK (1991) [ "The Early History of the Carp and its Economic Significance

in England"] Ag Hist Rev, 39 (II): 97–107. (another blacklisted site!? The early history of carp is apparently a very subversive topic)

Fish pond

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There is something, Sir, in fishponds, but what it is I leave to system builders and fish pond diggers betwixt'em to find out; but there is something under the first disorderly transport of the humorous, so unaccountably becalming in an orderly and a sober walk towards one of them...

Tristram Shandy, 1792[1]

Overview

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Basic structure of a fishpond

basic components/features of a well-designed pond.

History

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Prehistory

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Ancient history

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China
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Egypt
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Rectangular fishpond with ducks and lotus planted round with date palms and fruit trees, in a fresco from the Tomb of Nebamun, Thebes, 18th Dynasty
Small fishing pond
Vladimir Putin fishing with George Bush
Contemporary ponds used for farming fish in Mexio

"Gardens were much cherished in the Egyptian times and were kept both for secular purposes and attached to temple compounds. Gardens in private homes and villas before the New Kingdom were mostly used for growing vegetables and located close to a canal or the river. However, in the New Kingdom they were often surrounded by walls and their purpose incorporated pleasure and beauty besides utility. Garden produce made out an important part of foodstuff but flowers were also cultivated for use in garlands to wear at festive occasions and for medicinal purposes. While the poor kept a patch for growing vegetables, the rich people could afford gardens lined with sheltering trees and decorative pools with fish and waterfowl. There could be wooden structrures forming pergolas to support vines of grapes from which raisins and wine were produced. There could even be elaborate stone kiosks for ornamental reasons, with decorative statues."

"Temple gardens had plots for cultivating special vegetables, plants or herbs considered sacred to a certain deity and which were required in rituals and offerings like lettuce to Min. Sacred groves and ornamental trees were planted in front of or near both cult temples and mortuary temples. As temples were representations of heaven and built as the actual home of the god, gardens were laid out according to the same principle. Avenues leading up to the entrance could be lined with trees, courtyards could hold small gardens and between temple buildings gardens with trees, vineyards, flowers and ponds were maintained."

Syria
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  • Atargatis - " great goddess of northern Syria" - As Ataratha, doves and fish were considered sacred by her, doves as an emblem of the Love-Goddess, and fish as symbolic of the fertility and life of the waters.[2]… At her temples at Ascalon, Hierapolis Bambyce, and Edessa, there were fish ponds containing fish only her priests might touch.[3] Glueck noted in 1936 that "to this day there is a sacred fish-pond swarming with untouchable fish at Qubbet el-Baeddwī, a dervish monastery three kilometres east of Tripolis, Lebanon."[4]
Greece
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Rome
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Lampreys have long been used as food for humans. They were highly appreciated by ancient Romans.

Notoriously, Vedius Pollio kept a pool of lampreys into which slaves who incurred his displeasure would be thrown as food[5] – a particularly unpleasant means of death, since the lamprey "clamps its mouth on the victim and bores a dentated tongue into the flesh to ingest blood".[6]

Vedius Pollio was punished by Augustus for attempting to feed a clumsy slave to the lampreys in his fishpond.

...one of his slaves had broken a crystal cup. Vedius ordered him to be seized and then put to death, but in an unusual way. He ordered him to be thrown to the huge lampreys which he had in his fish pond. Who would not think he did this for display? Yet it was out of cruelty. The boy slipped from the captor’s hands and fled to Caesar’s feet asking nothing else other than a different way to die — he did not want to be eaten. Caesar was moved by the novelty of the cruelty and ordered him to be released, all the crystal cups to be broken before his eyes, and the fish pond to be filled in... – Seneca, On Anger, III, 40[7]

"every Roman wished to follow the example of Velins Pollio, who, in the time of Augustus flung such slaves as displeased him into his fishponds, to feed his lampreys"

  • Gardens of Lucullus – The fabled gardens of Lucullus were among the most influential in the history of gardening… Lucullus' rural villas in the hills at Tusculum, near modern Frascati, and at Naples were also set in lavish garden settings. Plutarch, 'Lucullus' ch. 37 mentions "the chambers and galleries, with their sea-views, built at Naples by Lucullus, out of the spoils of the barbarians.", and Pliny writes of Lucullus cutting a channel through a mountain on his Naples estate to allow seawater to circulate in his fishpond, which recalled the channel that had been cut through the isthmus at Mount Athos by the Persian king.[8] Plutarch, like most of Lucullus' Roman contemporaries, thought these occupations of Lucullus' retirement unbecoming to a Roman, and mere play:

Hawaii

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Middle ages

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Italy

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Garden of Villa d'Este. Fish ponds.
  • Villa d'Este - Italian villa - UNESCO world heritage site - The glory of the Villa d'Este was the system of fountains, fed by two aqueducts that Ligorio constructed from the River Aniene. In the centre of the garden, the alley of one hundred fountains (which actually had two hundred fountains), crossed the hillside, connecting the Oval Fountain with the Fountain of Rome, which was decorated with models of the famous landmarks of Rome. On a lower level, another alley passed by the Fountain of Dragons and joined the Fountain of Proserpina with the Fountain of the Owl. Still lower, an alley of fishponds connected the Fountain of the Organ to the site of a proposed Fountain of Neptune.[12]

England

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The modern era

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Modern writers

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16th century on

Starting with the reformation (16th century onwards), the earliest significant writer on fishponds during this period was Jan Dubravius, bishop of Olomouc in Bohemia,[13] who early in the 16th century published an influential five book treatise in Latin on fish ponds, dedicated to Anton Fugger and cited by Izaak Walton.

Includes a guide to fishponds of the time in Moravia, Bavaria and Saxony.

In book i. chap. iii., he refers to "the profits that were in those days derived from fish ponds in his native county. He instances those belonging to Janus of Berenstenie, "the rich ruler and alderman of Bohemia and Moravia," who he positively states annually derived three times the amount that Cato received from the ponds of Lucullus, during the minority of the latter, which in out currency would represent 9,376 pounds per year.


Contemporary fishponds

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Ornamental

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Recreational fishing

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Aquaculture

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Notes

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  1. ^ Laurence, Sterne (1792) The life and opinions of Tristram Shandy University of Lausanne, pp. 368–369.
  2. ^ http://www.thaliatook.com/OGOD/atargatis.html
  3. ^ Lucian, De Dea Syria; Diodorus Siculus II.4.2.
  4. ^ Glueck 1936: p. 374, note 4
  5. ^ Dio 52.23.2; Pliny the Elder, Natural History 9.39; Seneca the Younger, On Clemency 1.18.2.
  6. ^ Africa, p. 71, citing M. W. Hardisty (1971). The Biology of Lampreys. New York. pp. vol. I, pp. 147–161. ISBN 0123248019. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  7. ^ Thelatinlibrary.com
  8. ^ Pliny, IX.171 - also in this book are references to scientific observations carried out on Lucullus's fish.
  9. ^ AD 122, when Plutarch was writing
  10. ^ Then Hadrian
  11. ^ Plutarch, Life of Lucullus, 39
  12. ^ The present Fountain of Neptune was built in 1927
  13. ^ Hoare, 1870, p. 6.

References

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Ponds

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From Haiku#Examples... The best-known Japanese haiku[1] is Bashō's "old pond":

古池や蛙飛込む水の音
ふるいけやかわずとびこむみずのおと (transliterated into 17 hiragana)
furuike ya kawazu tobikomu mizu no oto (transliterated into romaji)

This separates into on as:

fu-ru-i-ke ya (5)
ka-wa-zu to-bi-ko-mu (7)
mi-zu no o-to (5)

Translated:[2]

old pond . . .
a frog leaps in
water’s sound

Galleries

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Sediments

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Sources needed

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Need proper sources for some of the following points (from - [10])...

  • "It’s hard for fish to evoke compassion. Unlike humans and other animals, they can’t express pain or fear through behaviours which are easy to recognise, such as vocalisation. They aren’t furry and cute with sad eyes."
  • "Fish with hook in its mouth Fish have nerve structures which are anatomically similar to those of humans and other mammals. The lips and mouth of fish are particularly well supplied with these pain specific nerve endings—the very area impacted upon by hook and line fishing."
  • "Fish avoid painful stimuli suggesting that they experience distress. Studies have also revealed that in a restrictive environment fish, like other animals in captivity, will exhibit abnormal behaviours indicating stress and distress."
  • Fishing affects more individual animals than any other human-based animal industry. In Australia there are more than 3 million recreational anglers and 24% of households fish regularly. The commercial ‘wild capture’ fisheries seek some 800 different marine and freshwater ‘seafood’ species – under 300 marketing names for domestic and overseas consumption. 241,000 tonnes of fish, crustacea (prawns, cabs etc) and molluscs (scallops, oysters etc) were commercially ‘harvested’ in the 2005/6 year in Australia (State and Commonwealth). This does not account for the fish taken by recreational fishers."
  • Trawling is one of the most common methods of commercial fishing in the world – and a system of fishing that eventually kills all in its path. Hundreds of different life forms are killed as trawl nets grind over the sandy bottom of the ocean. When fish in the nets are dragged up from the ocean depths the change in pressure (called barotrauma) causes their eyes to balloon and their swim bladders to burst. Many fish (and other aqautic animals) drown under the weight of all the other fish and creatures including starfish, crabs and shellfish. The unwanted catch is simply thrown back to the sea where many will subsequently die."
  • "Once caught either by hook or by net – most fish suffer an extended death through suffocation. In their death throes fish writhe, gasping and flapping their gills as they desperately try to get oxygen."
  • "Finning, long line fishing, purse seine nets and drift gill netting are all other methods of commercial fishing that cause suffering to the targeted fish. These methods of fishing do not discriminate – marine mammals such as dolphins, porpoises and seals, turtles and ‘non-target’ fish are also caught and suffer as a result."

Background

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From Moral status of animals in the ancient world

The 21st-century animal welfare and animal rights debates about how human beings ought to treat animals can be traced back to the ancient world.

The idea that the use of animals — for food, clothing, entertainment, and education — is acceptable springs mainly from two sources. First, there is the idea of a divine hierarchy based on the theological concept of "dominion," from Genesis (1:20-28), where Adam is given either ownership or stewardship over the non-human world. Closely related to this is the idea that animals are in some way defective, because they lack rationality and language, or even consciousness.

In philosophy

The philosopher and mathematician Pythagoras ( c. 580–c. 500 BCE), who has been called the first animal rights philosopher,[3] urged respect for animals, because he believed that humans and non-humans had the same kind of soul. Pythagoras believed that “there is one spirit which pervades, like a soul, the whole universe and also makes us one with irrational animals.” [4]

For Aristotle was the first to attempt a taxonomical hierarchy of animals.[5] Aristotle recognized some similarities between human and non-human species and he developed a sort of "psychological continuum", recognizing that human and non-human animals differ only by degree in possessing certain temperaments and that some non-humans possess analogous intellectual capacities to humans.[5] Yet, Aristotle claimed that the powers of rational thought and understanding were reserved to humans.[5] Aristotle argued that humans were the “masters” in his created hierarchal structure based upon the foregoing notion.[5]

[this sets a divide in thought which still echoes in current thinking]

In religion

The first chapter of Genesis describes how God gave human beings dominion over animals, tempered throughout the Torah, or Old Testament, by injunctions to be kind. Severing a limb from a live animal and eating it was forbidden (Genesis 9:4).

Both Hindu and Buddhist societies saw widespread vegetarianism from the third century BCE, in line with ahimsa, the doctrine of non-violence. Ryder writes that animals were thought to possess the same feelings as human beings, and several kings of ancient India built hospitals for sick animals. To kill a cow in Hinduism was as serious as killing a high-caste man, and the killing of a dog equivalent to killing an untouchable.

Human souls could be reborn as animals and insects if they had behaved badly, with all souls regarded as part of the Supreme Being. Failing to observe the duty to care could lead to bad karma, which increased the likelihood of returning as an animal next time round.[7]

The traditional Buddhist understanding of non-violence is not as rigid as the Jain one, but like the Jains, Buddhists have always condemned the killing of all living beings.[8][9] In most Buddhist traditions vegetarianism is not mandatory. Monks and lay persons may eat meat and fish on condition that the animal was not killed specifically for them.[10]

In the Laṅkāvatāra & Aṅgulimāla sutra the Buddha explicitly prohibits the eating of meat, fish and any animal products which are the result of harming and killing of any sentient being.

Background reference

Thomas Nagel's famous 1974 anti-reductionist essay; "What Is it Like to Be a Bat?".

See Thomas Nagel#Philosophy of mind

© 2000


Perpectives

Fish and pain can be approached from several directions:

  • religious
  • ethical/moral
  • philosophical
  • scientific
  • special interest groups

[Whether or not fish feel pain has some philosophical implication, concerning what is meant by "pain", and whether, or in what sense, the experience of pain depends on cognition and consciousness.]

[Darwin opened the idea that, as humans, we are related to other species]

[the question should perhaps be "in what sense do fish feel pain?", rather than "do fish feel pain?"]

[pro angling interests commonly point to the fact that many fish do not seem to experience pain when hooked in the roof of their mouth, as evidence that fish do not feel pain in any sense. ]


in The animal ethics reader Eds Armstrong SJ and Botzler RG, Routledge, 2003. ISBN 9780415275880

in Animal Consciousness and Animal Ethics: Perspectives from the Netherlands Eds Dol M, Kasanmoentalib S, Lijmbach S and Rivas, E. Pub. Van Gorcum. ISBN 9023232151.

  • Bermont, B (2001). "A Neuropsychological and Evolutionary Approach to Animal Consciousness and Animal Suffering". Animal Welfare Supplement, '10:47- 62.
  • Bermont, B (1997). "Consciousness or the Art of Foul Play", Journal of Agricultural and Environmental Ethics, 10 (3).

"The psychological literature about consciousness has been analyzed. It is argued that: 1) Only the higher symbolic cognitive powers like the ability to keep secrets, knowledge of self or self-consciousness, a long-term view on the future, the ability to determine long-term goals, and to freely plan future behavior, add positive fitness-value to consciousness. Without these higher intellectual abilities consciousness will have only negative fitness value and no positive one. The intellectual powers mentioned may therefore be considered as prerequisites for consciousness."

REVIEW: "For many years scientists within human and animal science have extensively discussed the philosophy of medicine, but never have both sides communicated on their concepts of health, quality of life and welfare, with each other. This book helps clarify the difficult but central notions of health and welfare by comparing the human and animal variants of these concepts. Split into three parts this book starts by presenting a background of some of the major theories of human health and welfare, among these are the bio-statistical theory, classical theories such as Aristotle and Bentham, as well as objectivist and subjectivist contemporary theories. This is followed by a detailed discussion of theories on animal welfare and health; these include coping, feeling and preference theories. The final part of the book tests a comprehensive conceptual framework of a holistic kind, which focuses on the individual's ability to achieve it's vital goals."

REVIEW: "While the problem of evil remains a perennial challenge to theistic belief, little attention has been paid to the special problem of animal pain and suffering. This absence is especially conspicuous in our Darwinian era when theists are forced to confront the fact that animal pain and suffering has gone on for at least tens of millions of years, through billions of animal generations. Evil of this sort might not be especially problematic if the standard of explanations for evil employed by theists could be applied in this instance as well. But there is the central problem: all or most of the explanations for evil cited by theists seem impotent to explain the reality of animal pain and suffering through evolutionary history. Nature Red in Tooth and Claw addresses the evil of animal pain and suffering directly, scrutinizing explanations that have been offered for such evil."

Do fish experience pain?

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The case against

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"James Rose of the University of Wyoming has put forth a strong argument for the inability of fish to experience pain that relies on analogy between human and fish neuroanatomy. Rose emphasizes the distinction between reaction to injury and psychological experience of pain and emphasizes that the existence of the former does not evince the existence of the latter. Indeed, human experiments have proven that pain is experienced in the brain and that sensation of and reaction to noxious, or potentially harmful, stimuli can occur without the experience of pain. The concept of nociception makes this possible."[11]

Nociception
External image
image icon Comparison of the human central nervous system with a fish[11]

"The term nociception refers to the detection of noxious stimuli by the nervous system. The peripheral nervous receptors we call nociceptors sense stimuli and report to the central nervous system where motor responses are initiated and the sensation of pain is perceived. Some fish species certainly do have nociceptive neurones analogous to those found in the human. However, this means only that these animals are capable of sensing noxious stimuli; it provides no evidence for the psychological experience of pain."[11]

Pain Related Chemicals

"Teleost nervous systems also produce opiate-related compounds and proteins similar to the GABA/benzodiazepen receptors that play a role in the sensation of human pain. However, these compounds are not exclusively related to pain in humans and may play other roles in the physiology of fish. For greater evidence of the psychological experience of pain it seems appropriate to examine the brain."[11]

Main anatomical regions of the vertebrate brain.
Dorsal view of the brain of the rainbow trout.
The Brain

"According to Bermond (1997) the highly developed neocortex of the human cerebral hemispheres is responsible for our ability to experience emotions and sensations such as pain. The existence of this feature in the fish brain would strengthen an argument for the ability of fish to experience pain. However, the fish brain is dominated by brainstem components and features very primitive cerebral hemispheres that lack neocortex. Humans require this neocortex for basic sensory functions as it is thought to be responsible for interpreting the sensory information received and processed by our brainstem and spinal cord. In fish, a higher level of cortical sensory interpretation appears nonexistent, since fish behaviour is unaffected by cortical damage. For example, cortical damage in a human may cause blindness whereas the complete removal of a fish’s cerebral hemispheres causes no apparent change in sensory-dependant behaviour."[11]

"If we assume, as Rose and Bermond do, that the neocortex is necessary for pain sensation, then we must admit that sensation of pain in any animal lacking an analogous structure is unlikely. Fish would

therefore lack the neurological capability to experience the negative psychological sensation of pain."[11]

Figure 1. "Comparison of human brain with a trout brain. A. Diagram of a midline view of the human brain. The cerebral hemisphere is shaded in darker gray and the brainstem is in lighter gray. B. Diagram of a midline view of a rainbow trout brain. The cerebral hemisphere (darker gray) is very small relative to the size of the brainstem (lighter gray). The white region at the left of the cerebral hemisphere is the olfactory bulb, which processes odor information. The olfactory bulb of a trout and many other fishes is large compared to the size of the brain as a whole, but the olfactory bulb in humans is relatively small. C. Diagram of the brain of a 12 inch rainbow trout shown at the same scale as the human brain diagram."[11]

Figure 2. "The diagram below shows the basic regions of the human central nervous system, the large cerebral hemispheres, the brainstem and the spinal cord."[11]

The case for

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"How convincing is the argument as stated above? Is the lack of certain so-called higher brain structures evidence enough to deny that fish feel pain? The following argument may refute such a claim quite effectively."[11]

Accessing Subjective Experience

"It cannot be denied that psychological states are entirely private experiences. This fact alone requires us to make inferences about subjective experiences of non-humans in one of two manners:"[11]

1. "by analogy between the behaviours and physiological states of humans and of animals"[11] 2. "by making the case that the existence of a subjective state is evolutionarily significant and a precondition for the species’ evolution"[11]

Argument by Analogy

"The first method is employed routinely by animal welfare scientists when assessing the experience of mammals and birds and has even been used to argue convincingly for the capacity of invertebrates to suffer (Sherwin 2001). In the argument outlined above, Rose makes a case by analogy to cast doubt upon pain sensation in fish by showing that fish neuroanatomy is sufficiently different from that of humans. The behavioural evidence provided on this site (kk) is similar to that used to explain painful experiences of mammals and birds and even human infants in other research (Dubner & Ren 1999, Sanford et al 1986, Anand & Craig 1996). If we use such indicators to describe pain in so-called higher vertebrates, then why not use them to describe pain in fish?"[11]

Argument by Evolutionary Necessity

"The second method is used quite eloquently by Dawkins when she says:"[11]

  • "Pain evolved because, by being unpleasant, it keeps us away from the larger evolutionary disaster of death. Pain is part of a mechanism for helping us to avoid immediate sources of injury, and also to refrain from repeating actions that have resulted in damage (1998)."[11]

"This argument is highly persuasive. Clearly any animal could not be successful unless it featured both a mechanism for detecting potentially harmful stimuli and a kind of negative or unpleasant psychological or subjective state or experience with which it could associate such stimuli. Fish, it appears, may have remarkably different systems of nociception and brain function from mammals and therefore may not experience the precise sensation of pain that humans do but this does not mean that fish are incapable of experiencing a negative psychological state analogous to human pain in response to noxious stimuli."[11]

"This reasoning is undoubtedly compelling. Though what is quite apparent from both of the arguments outlined above is that our current body of knowledge about the neuro-physiology of fish is inadequate for either argument to be entirely convincing. Therefore it is particularly relevant in this case to remember that "absence of evidence is not evidence of absence" (Sherwin, 2001). We must remain open-minded and recognize that our ability to answer the question "do fish feel pain?" with confidence is limited by the constraints of our own perception."[11]

References
  • Anand, KJS and Craig, KD. 1996. New perspectives on the definition of pain. Pain. 67: 3-6.
  • Bermond, B. 1997. The myth of animal suffering. In Dol, M, Kasamoentalib, S Lijmbach, S, Rivas, E and vandenBos, R (eds). Animal Consciousness and
  • Animal Ethics: Perspectives from the Netherlands. pp 125-143. Van Gorcum: Assen, The Netherlands.
  • Dubner, R and Ren, K. 1999. Assessing transient and persistent pain in animals. In: Wall PD and Melzack (eds) Textbook of Pain, 4th ed.. pp 359-369. Churchill Livingstone: Edinburgh, UK.
  • Sanford, J, Ewbank, R, Molony, V, Tavernor, WD, Uvarov, O. 1986. Guidelines for the recognition and assessment of pain in animals. Veterinary Record. 118: 334-338.
  • Sherwin, C. 2001. Can invertebrates suffer? Or, how robust is argument–by analogy? Animal Welfare. 10: S103-118.

Thrust and parry

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(or "The evolving debate") There are many reviews of the issues, but little experimental research.

Special interest groups

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PETA takes the uncompromising position that "fish feel pain".[12]

The issue of consciousness

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Pain in fish

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"The study is the work of James D. Rose, a professor of zoology and physiology at the University of Wyoming, who has examined data on animals' responses to pain. His report, published in the American academic journal Reviews of Fisheries Science, concludes that awareness of pain depends on functions of regions of the cerebral cortex which fish do not possess.

"Prof Rose, 60, said that previous studies which had indicated that fish can feel pain had confused "nociception" - responding to a threatening stimulus - with feeling pain.

"Pain is predicated on awareness," he said. "The key issue is the distinction between nociception and pain. A person who is anaesthetised in an operating theatre will still respond physically to an external stimulus, but he or she will not feel pain. Anyone who has seen a chicken with its head cut off will know that, while its body can respond to stimuli, it cannot be feeling pain."[13]Anglers are finally off the hook: fish feel no pain Telegraph, 5 May 2003.

"Rose argues that because fish don't have an adequately developed forebrain neocortex they are incapable of consciousness, and therefore cannot feel pain."

"According to James Rose, a professor of zoology at the University of Wyoming, and an admitted fisherman, "Awareness of pain in humans depends on specific regions of the cerebral cortex. Fishes lack these brain regions and thus the neural requirements necessary for pain experience." Rose believes that a fish's reaction to being hooked is an "escape reaction."

"Countering Rose's view is a recently released British study that claims fish do in fact feel pain. Lynne Sneddon and Michael J. Gentle of the Roslin Institute (the place that gave us Dolly the sheep), and Victoria Braithwaite of the University of Edinburgh, injected bee venom, or acetic acid, into the lips of some trout. They concluded the fish had polymodal nociceptors receptors that respond to tissue-damaging stimuli. Therefore, Sneddon and company state that fish feel pain"[14]

eard about Lynne’s rather controversial studies where the lips of live trout were injected with bee venom.

Lynne Sneddon: So I had to give the fish a painful stimulus which was a short term acute stimulus that lasted about three hours. And this had a major effect on behaviour, it adversely effected the behaviour; the fish didn’t feed, they performed quite strange anomalous behaviours—and also their physiology was affected—and these responses were similar to those seen in humans. So since these stimuli are painful to humans, then it’s likely that they’re painful to the fish.

Abbie Thomas: What sort of reactions did they display?

Lynne Sneddon: Well the performed quite strange behaviours where they rocked from side to side so they were situated on the bottom of the tank and they’d rock from side to side on either pectoral fin and that might be similar to stereotypical rocking you see in zoo animals and primates, and that’s thought to be an indicator of poor welfare.

The other thing we did was they rubbed the affected area against the sides of the tank and into the gravel—and that might be similar to rubbing behaviour where an animal rubs an affected area and it helps to reduce the intensity of pain, so when we stub our toe, the first thing you do is you start rubbing it, and that helps to reduce the pain that you’re feeling.

Rose's position

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"Human existence is dominated by functions of the massively developed cerebral hemispheres. Fishes have only primitive cerebral hemispheres and their existence is dominated by brainstem functions... Fish have the simplest types of brains, of any vertebrates, while humans, have the most complex brains of any species. All mammals have enlarged cerebral hemispheres that are mainly an outer layer of neocortex. Conscious awareness of sensations, emotions and pain in humans depend on our massively-developed neocortex and other specialized brain regions in the cerebral hemispheres. If the cerebral hemispheres of a human are destroyed, a comatose, vegetative state results. Fish, in contrast, have very small cerebral hemispheres that lack neocortex. If the cerebral hemispheres of a fish are destroyed, the fish’s behavior is quite normal, because the simple behaviors of which a fish is capable (including all of its reactions to nociceptive stimuli) depend mainly on the brainstem and spinal cord. Thus, a human’s existence is dominated by the cerebral hemispheres, but a fish is a brainstem-dominated organism."[15]

"The experience of pain depends on functions of our complex, enlarged cerebral hemispheres. The unpleasant emotional aspect of pain is generated by specific regions of the human cerebral hemispheres, especially the frontal lobes. The functional activity of these frontal lobe regions is closely tied to the emotional aspect of pain in humans and damage of these brain regions in people eliminates the unpleasantness of pain. These regions do not exist in a fish brain. Therefore, a fish doesn’t appear to have the neurological capacity to experience the unpleasant psychological aspect of pain. This point is especially important, because some opponents of fishing have argued that fish are capable of feeling pain because some of the lower, subcortical nervous system pathways important for nociception are present in fish. Obviously this argument has no validity because without the special frontal lobe regions that are essential for pain experiences, lower pathways alone can’t produce this experience. The rapid, well-coordinated escape responses of a fish to nociceptive stimuli are generated automatically at brainstem and spinal cord levels but, if a fish’s brainstem and spinal cord work like a humans (and it is very likely that they do) there is no awareness of neural activity occurring at these levels."[15]

Do fish feel pain?

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Do fish feel pain? Both sides say they have science on their side.

"According to some scientists, the brain of a fish is not equipped with certain structures needed to process pain, but others believe that fish nevertheless do sense some type of pain."[16]

"They have a neurologic input into their central nervous system that alerts them of possible tissue injury so they can make a reflexive response to protect themselves. Pain is believed by many to require higher order functions that a fish brain is too simple to have. Nonetheless, researchers are required to approach work with fish, and all other vertebrates, as if they could experience pain."[17]

  • pro People for the Ethical Treatment of Animals
  • 1979: pro paper sponsored by the Royal Society for the Prevention of Cruelty to Animals, reaches this conclusion: "The evidence suggests that all vertebrates (including fish), through the mediation of similar neuoropharmacological processes, experience similar sensations to a greater or lesser degree in response to noxious stimuli."
  • 2002 con Rose of the University of Wyoming reported in the American journal Reviews of Fisheries Science that "fish brains were not sufficiently developed to sense pain or fear. At the time he said that responding to threatening stimuli (nociception) was not the same as feeling pain".[18][19]
  • 2003 pro Sneddon - trout - "Their research, involving rainbow trout, showed the fish had receptors in their heads called polymodal nociceptors, which respond to tissue-damaging stimuli. The fish also showed "adverse behavioural and physiological changes" when they were subjected to noxious substances." After the team injected simulated bee venom (a chemical extract) into the lips of rainbow trout, the trout indicated pain by rocking with pain, much as mammals do, rubbing their lips on the gravel floor of the tank and on tank walls, andtaking three times longer than the control fish to resume eating after being 'stung' by the 'bees.'"[18][20][21]

From the introduction: "Therefore, if we can demonstrate that therainbow trout possesses the neural apparatus to detect noxious stimuli, then this confirms that the trout is capable of nociception, the simple detection and reflex response to a noxious stimulus (Kavaliers 1988; Bateson 1991). To suggest pain perception, it must be shown that any behavioural or physiological responses are not merely reflexive."[21]

"The criteria that must be met for animal pain are firstly, the demonstration of the sensory capability of detecting potentially painful stimuli, and secondly, the performance of adverse behavioural responses to a potentially painful event that are not simple reflexes."

From the discussion: "The results of the present study demonstrate nociception and suggest that noxious stimulation in the rainbow trout has adverse behavioural and physiological effects. This fulfils the criteria for animal pain as stated in the introduction"[21]

  • 2009: con Paper by Rose, initiated by The American Fisheries Society - a scientific organization of biologists, scientists, fisheries managers, and fish-culture experts -
  • 2009: pro Researchers at Purdue University subjected goldfish to potentially painful heat. "Half of the fish were injected with morphine, and the others received saline". "The fish given the morphine acted like they always had: swimming and being fish," Garner said. "The fish that had gotten saline - even though they responded the same in the test - later acted different, though. They acted with defensive behaviors, indicating wariness, or fear and anxiety."[30][31][32]
  • The Norwegian Research Council is funding a three year research project, scheduled to end in December 2011, into whether cod can feel pain.[33][16]


"Dr. James Rose of the University of Wyoming, who has studied animals’ reactions to painful stimuli for three decades, has concluded that fish do not have the brain system necessary to feel pain. They react to being hooked but don’t have the ability in its brain to define it as pain. In “Do Fish Feel Pain?” Rose wrote, “The facts about the neurological processes that generate pain make it highly unlikely that fish experience the emotional distress and suffering of pain. Thus, the struggles of a fish don’t signify suffering when the fish is seized in the talons of an osprey, when it is devoured while still alive by a Kodiak bear, or when it is caught by an angler.”

"In 2003, a study at Edinburgh University and the Roslin Institute in the United Kingdom — one that is used by the People for the Ethical Treatment of Animals in its Fishing Hurts campaign — concluded that fish feel “emotional stress” in response to pain stimuli. The study was based on subjecting anethesized trout to damaging stimuli. The research team, according to PETA, concluded that fish clearly experience pain in the same way as mammals, both physically and psychologically.

"Research into "fish-pain" was done by Drs. Sneddon, Braithwaite and Gentle from the Roslin Institute in the UK (the home of Dolly the Cloned Sheep) and the University of Edinburgh.

"The scientists tested rainbow trout - but only 20 of them. Now, "20" is not a very big sample size. This is true. I await a follow-up study with bigger numbers. But it's a start.

"Previous studies looked for pain receptors in fish with cartilaginous or non-bony skeletons (creatures such as sharks or manta rays), and could not find any. But trout (like us humans) have a bony skeleton, which is why the researchers chose them - and the results were startling.[34]

The International Association for the Study of Pain defines pain as:

"An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage… activity induced in the nociceptors and nociceptive pathways by a noxious stimulus is not pain, which is always a psychological state."[35]

Timeline

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  • And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea...Genesis 1:26-8.[6]

See also

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Notes

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  1. ^ Higginson, William J. The Haiku Handbook, Kodansha International, 1985, ISBN 4-7700-1430-9, p.9
  2. ^ Translated by William J. Higginson in Matsuo Bashō: Frog Haiku (Thirty Translations and One Commentary), including commentary from Robert Aitken’s A Zen Wave: Bashô’s Haiku and Zen (revised ed., Shoemaker & Hoard, 2003)
  3. ^ Violin, Mary Ann. "Pythagoras—The First Animal Rights Philosopher," Between the Species 6:122–127, cited in Taylor, Angus. Animals and Ethics. Broad view Press, p. 34.
  4. ^ Gary Steiner, Anthropocentrism and its Discontents: The Moral Status of Animals in the History of Western Philosophy, University of Pittsburgh Press, 2005, at page 47.
  5. ^ a b c d Mark R. Fellenz, The Moral Menagerie: Philosophy and Animal Rights, University of Illinois Press, 2007, p. 90.
  6. ^ a b Cited in Ryder, Richard D. Animal Revolution: Changing Attitudes towards Speciesism. Berg, 2000, pp. 23-24.
  7. ^ Ryder, Richard D. Animal Revolution: Changing Attitudes towards Speciesism. Berg, 2000, p. 21.
  8. ^ Sarao, K.T.S.: The Origin and Nature of Ancient Indian Buddhism, Delhi 1989, p. 49; Goyal p. 143; Tähtinen p. 37.
  9. ^ Lamotte, Etienne: History of Indian Buddhism from the Origins to the Śaka Era, Louvain-la-Neuve 1988, p. 54-55.
  10. ^ Sarao p. 51-52; Alsdorf p. 561-564.
  11. ^ a b c d e f g h i j k l m n o p q Do fish feel pain? Royal (Dick) School of Veterinary Studies. Retrieved 19 Nay 2009.
  12. ^ Fish feel pain Position statement by PETA.
  13. ^ Block quote
  14. ^ Hooked! Ouch?: Fish, they say, feel pain National Review Online, 5 June 2003.
  15. ^ a b Do fish feel pain. Undated essay by James D. Rose, University of Wyoming.
  16. ^ a b Can fish feel pain?
  17. ^ Can fish feel pain - please explain in detail?
  18. ^ a b Can fish feel pain? The argument continues
  19. ^ Rose JD (2002) The neurobehavioral nature of fishes and the question of awareness and pain Reviews in Fisheries Science, 10:1-38
  20. ^ Trout trauma puts anglers on the hook? Royal Society Science News. 30 April 2003.
  21. ^ a b c Sneddon LU, Braithwaite VA and Gentle MJ (2003) "Do fish have nociceptors: Evidence for the evolution of a vertebrate sensory system" Proceedings of the Royal Society: Biological Sciences, 270 (1520)
  22. ^ Rose, J.D. 2003. A Critique of the paper: "Do fish have nociceptors: Evidence for the evolution of a vertebrate sensory system"
  23. ^ Rose, J.D. 2003. A Critique of the paper: "Do fish have nociceptors: Evidence for the evolution of a vertebrate sensory system" published in Proceedings of the Royal Society: Biological Sciences. 270(1520):1115-1121
  24. ^ Goldfish remember pain
  25. ^ Painful memories for goldfish Telegraph, 30 Jan 2006
  26. ^ Dunlop R, Laming P (2005) "Mechanoreceptive and nociceptive responses in the central nervous system of goldfish (Carassius auratus) and trout (Oncorhynchus mykiss)" The Journal of Pain, 6(9):561-568.
  27. ^ Millsoppa S and Laming P (2008) "Trade-offs between feeding and shock avoidance in goldfish (Carassius auratus)" Applied Animal Behaviour Science, 113 (1-3) 247-254.
  28. ^ Arlinghaus R, Cooke SJ, Schwab A and Cowx IG (2007) "Fish welfare: a challenge to the feelings-based approach, with implications for recreational fishing," Fish and Fisheries, 8 (1): 57-71. Download
  29. ^ Huntingford F, Adams C, Braithwaite VA, Kadri S, Pottinger T, Sandoe P and Turnbull JF (2007) "The implications of a feelings-based approach to fish welfare: a reply to Arlinghaus et al." Fish and Fisheries, 8: 277-280.
  30. ^ Fish feel pain, Purdue team concludes Purdue University, 29 April 2009.
  31. ^ Fish may actually feel pain and react to it much like humans Purdue University, 29 April 2009.
  32. ^ Nordgreen J, Garner J, Janczak A, Ranheim B, Muir W and Horsberg T (2009) [linkinghub.elsevier.com/retrieve/pii/S0168159109001051 "Thermonociception in fish: Effects of two different doses of morphine on thermal threshold and post-test behaviour in goldfish",] (Carassius auratus)"], Applied Animal Behaviour Science, 119(1) 101-107.
  33. ^ Nociception and potential pain perception in Atlantic cod (Gadus morhua) Norwegian Research Council project, 1 August 2008 to 31 December 2011.
  34. ^ Do fish feel pain?
  35. ^ International Association for the Study of Pain: IASP Pain Terminology Retrieved 26 May 2009.

References

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book
con
pro
neutral
overview
consciousness
  • It is difficult to say what is meant by consciousness. The International Dictionary of Psychology (ed. Stuart Sutherland, 1989) goes so far as to define it as follows:
"Consciousness: The having of perceptions, thoughts and feelings; awareness. The term is impossible to define except in terms that are unintelligible without a grasp of what consciousness means. Many fall into the trap of confusing consciousness with self-consciousness - to be conscious it is only necessary to be aware of the external world. Consciousness is a fascinating but elusive phenomenon: it is impossible to specify what it is what it does or why it evolved. Nothing worth reading has been written about it."
consider these


commentaries


unprocessed

Do crabs feel pain

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  • Swarm intelligence of fish schools
  • Migratory Behavior
  • social structures: school vs. shoal vs. solitary swimmers).
  • Shoaling: the behaviour of certain species of aquatic animals (anchovy, squid, juvenile opaleye) to swim in large groups for protection against predators.
  • Social behavior and group dynamics: Group living is a basic life history characteristic of many fishes, with twenty five percent of all species forming schools or shoals during their life, and fifty percent during larval and juvenile stages (Radakov, 1973; Pavlov and Kasumyan, 2000). Pavlov and Kasumyan (2000) define a fish school as having all individuals oriented in the same direction, situated at a certain distance from each other, and unitary in all movements (polarized). Shoaling, in contrast, is a simple, spatial aggregation of fish attracted by a stimulus occurring independently of each other with no mutual attraction between individuals (non-polarized). Schooling and shoaling behaviors are complex social behaviors utilized by a wide diversity of fish species to increase individual fitness and propagate their genes in the population (Partridge, 1982) by providing defense from predation while increasing reproductive, foraging and migration efficiency. These behaviors have predictable structures, shapes, and responses to threats and environmental fluctuations. In addition, these behaviors are intimately tied to, and regulated by, the visual and lateral line systems, and are developed as soon as fish are able to swim and feed (Pavlov and Kasumyan, 2000).

Countering the attacks of predators

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Pitcher (1993) lists nine categories "defining the ways in which fish shoals may counter attacks of predators":

  • Avoidance – "Avoiding coming into the attack range of the predator. Predator may or may not be detected."
  • Dilution – "Reduction of risk for an individual member of the group as group size increases because predator is attacking only one of the group (or strictly, less than the total number). Predator is detected."
  • Abatement – "Reduction of risk with group size for an individual member od a population because of search and dilution. Predator is detected."
  • Evasion – "Reducing the success of an attack by moving out of strike range of a detected predator by beating the predator's manoeuvrability during a strike. May apply to individual behaviours (eg, skittering) or to the group as a whole (eg, flash expansion)."
  • Detection – "An individual becoming aware of the presence of a predator, usually (but not always) denotedby some small behavioural clue signalling alertness. Sensory clues from the predator may be direct (visual, auditory, chemosensory) or indirect, mediated by hanges in neighbour fishes behaviour signalling alertness."
  • Mitigation – "Reducing the probability of success of an attack which has already been launched by a detected predator."
  • Inspection – "Gaining information about a potential predator while approaching it, and then returning to the group."
  • Inhibition – "Reducing the likelihood of a detected and attacking predator launching a strike."
  • Confusion – "Reducing the succes of an attack that has been launched, by beating the predator's sensory (or cognitive) capacity."

Herrings

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Notes

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References

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Fish migration

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Migration patterns

Cobia make seasonal migrations along the coasts in search of water in their preferred temperature range. Wintering in the Gulf of Mexico, they migrate north as far as Maryland in the Summer, passing East Central Florida in March.



Muroami

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"Muro-ami, a Japanese term for the type of net used, refers to a method to catch elusive reef fish that are difficult to harvest. According to the ILO, fishing corporations employ children between 12 and 14 years of age, who spend 10 months a year out at sea, swimming and diving to a depth of 100 feet to attach nets to coral reefs. These children have no protective swimwear and are subjected to needlefish and shark attacks, and diseases like typhoid." Victoria Rialp, Children and Hazardous Work in the Philippines (Geneva: International Labor Organization, 1993) 6-8 [hereinafter Rialp]. See also Professor Nymia Simbulan, Children in Trouble: Its Socio-Economic Dimensions (unpublished manuscript, n.d.) 16 [on file] [hereinafter Simbulan]. See also Henk van Oosterhout, "Child Labor in the Philippines: The Muro-Ami Deep Sea Fishing Operation," in Combating Child Labor (Geneva: International Labor Organization, 1988) 109-122.[1]

"illegal method of fishing that originated from the Japanese in the early 1900s and this fishing technology became widespread across southeast asia and thereby including the Philippines. Muro-Ami has its roots in Japan"[2]


"Muro Ami is a film that depicts one of the worst forms of child labor in the illegal fishing system. Fredo is the ruthless captain of 150 Muro Ami divers. The illegal fishing is done by pounding and crushing corals underwater to scare the fishes and luring them towards the nets. With a high quota to meet, Fredo forces the divers mostly children, to accomplish at least eight dives a day to meet their goal before the millennium. Tired and harassed after the burdening task being given to them, the children have to make do in subhuman conditions in the Aurora, the Muro Ami boat. They sleep in rat-infested bunks and are fed only twice a day. Life above the boat is much worse than the suffering the children encounter beneath the sea. For every dive, a child's life is perilously in danger."[3]

"Deep­sea fishing - In many Asian countries, especially Myanmar (Burma), Indonesia, the Philippines and Thailand, children work in muro­ami fishing, which involves deep­sea diving without the use of protective equipment. Children are used to bang on coral reefs to scare the fish into nets. Each fishing ship employs up to 300 boys between 10 and 15 years old recruited from poor neighbourhoods. Divers reset the nets several times a day, so that the children are often in the water for up to 12 hours. Dozens of children are killed or injured each year from drowning or from decompression illness or other fatal accidents from exposure to high atmospheric pressure. Predatory fish such as sharks, barracudas, needle­fish and poisonous sea snakes also attack the children." [4]

"The muroami fishing technique, employed on coral reefs in Southeast Asia, uses an encircling net together with pounding devices. These devices usually comprise large stones fitted on ropes that are pounded onto the coral reefs. They can also consist of large heavy blocks of cement that are suspended above the sea by a crane fitted to the vessel. The pounding devices are repeatedly and violently lowered into the area encircled by the net, literally smashing the coral in that area into small fragments in order to scare the fish out of their coral refuges. The "crushing" effect of the pounding process on the coral heads has been described as having longlasting and practically totally destructive effects."wiki.answers

From Fishing nets...

"MURO-AMI is a system of drive-in net fishing that originated in Okinawa in the early 1900s and progressed with Japanese expansion and economic penetration to Southeast Asia and the Philippines. From an extremely extractive and economically successful fishing practice in the Philippines, using about fifteen divers, swimmers, and fishers around 1930, muro-ami transformed over time, scaling up in response to the post war demand from growing cities, until as many as three hundred boys or young men are employed nowadays as swimmers and divers. Despite scaling up and having a large labour force, muro-ami still maintains pre-capitalist labour relations and systems of dependency and reciprocity that bind impoverished parents to give up their youth to a life at sea, regardless of the dangers."

"The MURO-AMI net is made up of an enormous bag and two wings that each stretches almost three-quarters of a kilometre. The bag net is secured to the seabed by about twenty young divers, youths that free dive to depths of up to eighty feet to attach the net to the seabed. The children swim along the surface, from the end of the wings, carrying 25 metre long 'scarelines' with attached banners and a rock or 'two-eyed' chain as a weight that bangs on the coral reefs, scaring fish from their protective environment, and driving them with the current into the bag net. The divers then dislodge the net from the seabed, removing the rocks, and at the same time detaching the wings, ready to haul the bag with the fish to the surface. The net is cast up to ten times a day, with children spending extended periods in the water, fighting exhaustion and pushing themselves to the limits of their endurance. The work is extremely hazardous, with children diving without protective clothing or gear, except for home made wooden goggles. Every year children lose their lives, their hearing or are maimed."

"The ships on which the children are housed are unseaworthy, stinking Dickensian hulks, overcrowded, unsanitary and accommodating as many as four hundred and fifty fishers, some as young as seven and many around fifteen. Fleets stay out at sea for up to ten months, with the 'mother ship' transporting the catch to the markets and returning with ice and provisions. They scour strand coastal foreshores, coral reefs and atolls, moving constantly in search of new ground, causing considerable damage and species depletion. The system intrudes on the communal, coastal fishing communities, threatening their livelihood, as well as destroying biodiversity of coastal fishing grounds. Muro-ami still survives today, operating out of two fishing communities in Cebu, in the Visayas."

Source: The muro-ami system, a case study

"MURO-AMI was banned in 1986 after a national outcry when bodies of 100 Muro-ami victims, mostly children who were unable to escape from the nets after diving, were found in a graveyard along the shores of Panlaitan Island in Busuanga (Palawan)".

Asia Observer (May 23, 2001)

"Muroami The Muroami fishing technique, employed on coral reefs in Southeast Asia, uses an encircling net together with pounding devices. These devices usually comprise large stones fitted on ropes that are pounded onto the coral reefs. They can also consist of large heavy blocks of cement that are suspended above the sea by a crane fitted to the vessel. The pounding devices are repeatedly and violently lowered into the area encircled by the net, literally smashing the coral in that area into small fragments in order to scare the fish out of their coral refuges. The "crushing" effect of the pounding process on the coral heads has been described as having longlasting and practically totally destructive effects."Destructive fishing practices United Nations Atlas of the Oceans.

"Muroami netting is a dangerous fishing practice that has led to extensive coral reef deterioration in Southeast Asia. Fishermen use a combination of nets that are weighted and decorated with brightly colored plastic strips with pounding devices in order to startle and herd reef fish. The pounding devices are usually large stones on ropes or cement attached to a crane fitted to the fishing vessel. The weights are lifted and dropped repeatedly along the reef, breaking live coral along the way. In many counties that use this practice, as many as 300 young boys, 10 to 15 years old, are used to set the nets and bang on the coral. The practice was banned in the Philippines in the 1980s, but continues illegally in some places." [5]

  • Carpenter, K.E. and A.C. Alcala (1977) Muro-ami and Kayakas reef fisheries, benefit or bane? Philipp. J. Fish. 15(2):217-235.

"Coral reefs, the storehouses of much of the world’s marine biodiversity, and the source of many socio-economic benefits, are in decline worldwide. The causes of the ‘coral reef crisis’ are complex but there is general agreement that two broad categories of stress are involved: global-scale climatic changes induced by production of greenhouse gases, and local-scale impacts. The major feature of climate change affecting coral reefs is rising sea temperature, which has caused widespread coral bleaching and is implicated in increased occurrence of coral diseases and reduced rates of calcification. Local impacts on coral reefs stem from natural phenomena, such as storms, and from human populations in coastal areas, which are large and growing. The local human impacts include increased nutrient and sediment loads, habitat modification, destructive fishing and chronic overfishing. The losses of biodiversity, and lost opportunities for coastal communities to earn sustainable incomes from coral reefs, that can result from local human impacts are illustrated by blast, cyanide and muro-ami fishing. These destructive methods reduce the physical complexity and live coral cover of reefs and, because degraded reefs support fewer fish, ultimately remove the basis for long-term fish productivity. In Indonesia alone, blast fishing is estimated to have resulted in a loss of US$3.8 billion over 25 years."[6]

Ocean and Coastal Management, 49, 976-985pp.

Ring of fire

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Upwelling and gyres

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Upwelling Upwelling and downwelling influence sea-surface temperature and biological productivity. Upwelling waters may originate below the pycnocline and are therefore colder than the surface waters they replace. Sometimes upwelling waters are confined to the mixed layer depending on the thickness of the warm layer. You may have experienced upwelling at the beach on a windy day when the warm surface water was blown offshore and replaced by chilly water from below. Where the thermocline is shallow, the upwelling waters are usually rich in the dissolved nutrients (e.g., nitrogen and phosphate compounds) required for phytoplankton growth. This nutrient transport into the surface waters where sunlight, also required for phytoplankton growth (photic zone), is present, results in rapid growth of phytoplankton populations. Since phytoplankton form the base of marine food webs, the world's most productive fisheries are located in areas of coastal upwelling that bring cold nutrient rich waters to the surface (especially in the eastern boundary regions of the subtropical gyres); about half the world's total fish catch comes from upwelling zones. On the other hand, in zones of coastal downwelling, the surface layer of warm, nutrient-deficient water thickens as water sinks. Downwelling reduces biological productivity and transports heat, dissolved materials, and surface waters rich in dissolved oxygen to greater depths. This occurs along the west coast of Alaska in the eastern boundary region of the Gulf of Alaska gyre (driven by winds in the Aleutian low).[7]

Alternate upwelling of nutrient poor and nutrient rich waters off the coast of Ecuador and Peru are associated with El Niño and La Niña episodes in the tropical Pacific. During El Niño the pycnocline is so deep that the upwelled waters come from the nutrient poor waters above the pycnocline. In extreme cases, nutrient-deficient waters coupled with over-fishing cause fisheries to collapse bringing about severe, extended economic impacts.[7]

Oceanic futures like fronts, eddies, gyres and upwelling areas plays major role in supply of nutrients in oceanic waters. Most of the very good fishing grounds of the world are located in the areas, where the upwelling is found to occur. Coastal upwelling is a process by which nutrient rich subsurface cold waters brought to the surface near the coast. Fronts are the zones, where the convergence of two water masses with different properties takes place. Gyres are circular water masses formed by meandering currents, similarly eddies are formed due to circular movement of water. Such locations are rich in nutrient for the sustenance of fishing resources. These futures are found to be good fishing grounds due to availability of nutrients rich waters.

Map of Ocean Gyres

Ocean gyres are large-scale circling ocean currents caused by the Coriolis effect[8] Some major gyres are:

The currents of the North Pacific Gyre

This gyre comprises most of the northern Pacific Ocean. It is located between the equator and 50º N latitude and occupies an area of approximately ten million square miles (34 million km²). The North Pacific Gyre has a clockwise circular pattern and comprises four prevailing ocean currents: the North Pacific Current to the north, the California Current to the east, the North Equatorial Current to the south, and the Kuroshio Current to the west.
An accumulation of marine debris known as the "Great Pacific Garbage Patch" is collecting in the gyre.[9]

The center of a subtropical gyre is a high pressure zone. Circulation around the high pressure is clockwise in the northern hemisphere and counterclockwise in the southern hemisphere, due to the Coriolis force. The high pressure in the center is due to the westerly winds on the northern side of the gyre and easterly trade winds on the southern side of the gyre. These cause frictional surface currents towards the latitude at the center of the gyre. The buildup of water in the center of the gyre creates equatorward flow in the upper 1000 to 2000 meters of the ocean, through rather complex dynamics. This equatorward flow is returned poleward in an intensified western boundary current (Western intensification).

The intensified western boundary current of the North Atlantic's subtropical gyre is the Gulf Stream; in the North Pacific it is the Kuroshio; in the South Atlantic, it is the Brazil Current; in the South Pacific, it is the East Australia Current; in the Indian Ocean, it is the Agulhas Current.

Subpolar gyres form at high latitudes (around 60 degrees). Circulation of surface wind and ocean water is counterclockwise in the Northern Hemisphere, around a low pressure system (such as the persistent Aleution Low and the Icelandic Low). Surface currents generally move outward from the center of the system. This drives Ekman transport which creates an upwelling of nutrient-rich water from the lower depths.[10]

Subpolar circulation in the southern hemisphere is dominated by the Antarctic Circumpolar Current due to the lack of large landmasses breaking up the Southern Ocean. There are minor gyres in the Wendall and Ross Seas, which circulate in a clockwise direction.[11]



Fixed harbour defences

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Fixed harbour defences are ground installations used in time of war to defend harbours and ports from attack by sea. In the past, the attack might come from Viking ships, pirate ships or naval ships. In the 20th century the attack could also come from submarines, planes or missiles.

Some examples of fixed harbour defences are fortified structures protecting personnel and providing a platform for devices that hurl missiles; underground bunkers protecting supplies, power generators and control rooms; defensive barriers across the harbour entrance; and arrays of mines on the seabed of the harbour which can be selectively triggered from the shore. By contrast, some examples of harbour defences which are mobile, and not fixed, are fire ships, harbour defense launches, dive bombers, and infantry or tank divisions.

Apart perhaps from the use of deep bunkers, traditional fixed harbour defences are not used these days. Modern missile and monitoring systems, with their long range and pin point targeting capabilities, render traditional fixed defences irrelevant.

History

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The Roman Empire fortification system of the Saxon Shore at the end of the 3rd century
Siege of Constantinople

Fortifications and barriers

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The classic fixed harbour defence was the fort. Towards the of the 3rd century the Roman Empire established a network of mainly coastal fortifications on both sides of the English Channel. This defence system, called the Saxon Shore, defended many harbours, possibly from seaborne piracy.

During the 885-886 Siege of Paris, the Franks built fortified bridges to defend the Seine; unable to progress past these, the Vikings created fire ships by filling three warships with combustible material and pulled them upriver in a failed attempt to destroy them.[12]

Many coastal forts incorporated harbour facilities which enabled supply from the sea in times of land siege. Some castles, such as Conwy, had projecting spurs with towers acted as breakwaters as well as defensive structures.[13]

By the later medieval period it was customary for towns on the coast or navigable rivers to defend their harbours and waterways by chains or booms; this also facilitated the collection of tolls.[14] These could be operated by windlasses or pulleys located in boom towers.[15] At Harfleur, at the 1415 siege during the Hundred Years' War, the port's iron chain defences were supplemented by sharpened stakes driven into the riverbed.[16]

The 15th century writer Gutierre Diaz de Gamez recorded an attack on Marseilles in 1404:

"A strong chain of iron closes or frees the [harbour] entrance, which is very narrow. This chain is riveted to a great lighthouse in the middle of the harbour, so that no ship can come in or go out without leave.[17]

Diaz de Gamez goes on to describe a signal staff on an island just off shore; it was fitted with two sails, one the square sail from a ship, the other a triangular sail from a galley. A lookout keeps watch and when he spies a boat, he lowers the relevant sail to warn the town when a ship approaches.[17]

Catapults and Greek fire

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This possibly anachronistic lithograph from an 1869 Harper's Magazine depicts a 13th century engine for throwing Greek fire in a barrel.

Fortifications provided protection for infantry or cavalry, and also provided protected platforms for devices that could hurl things at naval boats. Siege catapults were used in 400-300 BC, both in China[18] and Greece[19]

Automated peer review

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You may wish to browse through User:AndyZ/Suggestions for further ideas. Thanks, Geronimo20 (talk) 21:29, 7 June 2009 (UTC)

  1. ^ The Philippines U.S. Department of Labor: Bureau of International Labor Affairs. Retrieved 19 January 2009.
  2. ^ [1]
  3. ^ MURO AMI: Reef Hunters
  4. ^ IOL: ILO Calls for Immediate Action Against Intolerable Forms of Child Labour Press release: 12 November 1996
  5. ^ McClellan, Kate and Bruno, John (2008) Coral degradation through destructive fishing practices Encyclopedia of Earth. Retrieved 25 Oct 2008.
  6. ^ Bell, JD; Ratner BD; Stobutzki, I and Oliver, J (2006) Addressing the coral reef crisis in developing countries. Ocean and Coastal Management, 49, 976–985
  7. ^ a b Wind Driven Surface Currents: Upwelling and Downwelling
  8. ^ Heinemann, B. and the Open University (1998) Ocean circulation, Oxford University Press: Page 98
  9. ^ "New 'battle of Midway' over plastic". BBC News. 26 March 2008. Retrieved 2008-04-01.
  10. ^ Wind Driven Surface Currents: Gyres
  11. ^ Cite error: The named reference SIO210slides was invoked but never defined (see the help page).
  12. ^ Bennett et al, pp 221-222
  13. ^ Creighton and Higham, p 99
  14. ^ Creighton and Higham, pp 40-41
  15. ^ Creighton and Higham, p 118
  16. ^ Kaufmann and Kaufmann, p 151
  17. ^ a b Diaz de Gamez, p 60
  18. ^ Liang (2006)
  19. ^ Rihall (2007)

END FISH PONDS

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end fish ponds


Distribution

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Polar life

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Image of an ice wall and ocean floor at Explorer's Cover, New Harbor, McMurdo Sound. Visible species include the antarctic scallop (Adamussium colbecki), the common antarctic sea urchin (Sterechinus neumayeri), a stalk-like bush sponge (Homaxinella balfourensis), a brittlestar (Ophionotus victoriae), seaspiders (Colossendeis sp.)
Cold currents

"Cold water currents flow from the polar areas towards the equator. Unlike faster warm currents, cold currents aren’t very useful for navigation but they do bring nutrients with them. An example is the Humboldt Current which flows north from the Antarctic along the Pacific coast of Chile. The nutrient-rich water forms the basis for life that thrives under the intense sunlight near the equator. This, in turn, provides food for near surface predators that can cope with the cooler water conditions. Even tropical fish are able to take advantage of the edges of cold water currents. The Humboldt Current reaches Panama in Central America where sailfish feed on schools of anchoveta. Cold currents tend to flow on the eastern side of the great ocean basins. The cold California Current travels south along the Pacific coast of North America. In summer, it can support subtropical species such as striped marlin which feed on mackerel and sardines, but in winter the water cools and the fish are forced to head south."[1]

"North of the Arctic Circle and south of the Antarctic Circle are the polar regions"

"Fish: About 200 kinds of fish live in the Antarctic. The largest is the Antarctic cod, which grows to 1.5 m and weighs 25 kg. Other fish include plunder fish, dragonfish, icefish, eel-pouts, sea snails, rat-tailed fish, hagfish, barracuda, lantern fish and skates. Some Antarctic fish are the only vertebrates that have no hemoglobin in their blood. This makes their blood move more slowly, so they can save energy. Ice fish and cod can survive in the Antarctic because they have glycoproteins, or antifreeze, in their blood."[2]

Crocodile icefish larvae
Antarctic cod

Most of the Antarctic coastline is hidden beneath the ice flowing off the continent. Beneath the seemingly lifeless expanses of pack-ice and sea-ice lies a much more rich and varied world of animals than on land. The factor which has the greatest effect on life in the Southern Ocean is not temperature but light. Without light plants cannot grow, and without plants there is no food for the animals at the bottom of the Antarctic food chain."[3]

Phytoplankton: "The food chain is based on phytoplankton, a varied group of tiny free floating plants. In spring and early summer their numbers increase rapidly, producing "blooms" like a think pea soup which can cover thousand of square kilometres of the ocean. These blooms provide a food source which is 300-400 times more concentrated than normal for a variety of zooplankton (tiny animals, especially copepods and krill, which in turn provide food for fish, seals, whales and penguins. Not surprisingly, zooplankton grow rapidly, increasing their body weight by around 5% a day over the short summer."[3]


"Antarctic krill are tiny shrimplike creatures. Antarctic krill is one of 85 species of krill found in the world. Krill swim in schools thousands of feet wide and look like a red wave at the bottom of the sea. They rise to the surface only at night. They are important in the Antarctic food chain. Krill feed on diatoms, tiny algae that have a hard skeleton, algae and phytoplankton or tiny plants. Birds, fish, squid, seals and whales eat krill."[2]

Krill: "a Norwegian whaling term meaning "small fry", refers to many species of planktonic crustacea. It is the most commercially important and so its biology is the best known. Surprisingly, it is poorly adapted to its environment. It is heavier than water and has to work hard just to keep afloat. For this, it has five pairs of legs for swimming, and also several more that form a net to filter its food. Krill are omnivores; they filter with the fine hairs on their thoractic appendages a wide variety of microorganisms and other crustacea from the water. They are also cannibalistic. Krill spawn in summer, and mature females can do so twice a season. They lay 2000-3000 eggs each time and the eggs sink into deep water where they are carried southward on the currents to the edges of the continent. There they hatch into larvae, which go through several stages as they gradually rise, emerging on the surface as adults in two or three years. Krill live a long time for plankton, up to seven years. In winter, they feed on algae on the underside of the pack ice. They shrink on this sparse diet, but make up for it the following summer when the phytoplankton blooms once more."[3]

Killer whales (orca) are apex predators. They hunt practically anything, including tuna, smaller sharks and seals.

"There live only 120 species of fish in the waters south of the Antarctic Convergence. 90 per cent of the total number of individual fish belong to the well studied group, the Notothenioidea. This sub-order is divided into four families: Antarctic cod, plunder fish, Dragonfish and ice fish."[3]

"There are two groups of whales in the Antarctic, six species of baleen whales and four species of toothed whales. Baleen is a hairy filter in the whale's mouth. It keep the krill, small fish and other food in and allows the water the whale gulped in with the food to flow out. Baleens include the bluewhale, the largest in the world... Other baleens are the fin, the southern right whale, the sei, the minke and the humpback. Toothed whales eat fish and squid and include the sperm whale, the smaller bottlenose whale, and the southern four-tooth whale."[2]

"Killer whales, or orcas, are the largest members of the dolphin family.They live in most ocens, but mainly in the Arctic and Antarctic.... Killer whales live in groups, or pod, of about 100... "[2]

"Seals are well adapted to cold Antarctic waters. Some have layer of dense fur and others a layer of blubber beneath the skin, which is equally effective in the air or under water. Seals are divided into two main types: The true of "earless" seals, which evolved from otter-like ancestors. The otariids is the other type, which includes fur seals and sealions. They have visible earflaps, and use all their limbs for locomotion on land , which they do very well."[3]

Antarctic seals: weddell seal, ross seal, crabeater seal (Lobodon carcinophagus), elephant and leopard seal

Crabeater seals "grow up to 2.7m long and have a weight of over 250kg. With a world population estimated at 40 million, this seal is one of the world’s most abundant large mammals. Crabeater seals are now the single biggest consumers of krill, accounting for 63 million tonnes a year. This is more than all the remaining baleen whales put together. Their numbers have increased enormously in the last 50 years as whales were hunted almost to extinction. For whales to make a comeback the crabeater population may have to fall, but it is not clear how this could happen."[3]

A census of sea life carried out during the International Polar Year and which involved some 500 researchers is due for release in 2010. The research is part of the global Census of Marine Life (CoML) and has disclosed some remarkable findings. More than 235 marine organisms live in both polar regions, having bridged the gap of 12,000 km (7,456 mi). Large animals such as some cetaceans and birds make the round trip annually. More surprising are small forms of life such as mudworms, sea cucumbers and free-swimming snails found in both polar oceans. Various factors may aid in their distribution - fairly uniform temperatures of the deep ocean at the poles and the equator which differ by no more than 5 °C, and the major current systems or marine conveyor belt which transport egg and larvae stages.[4]

"90 per cent of the total number of individual fish belong to the well studied group, the Notothenioidei. This sub-order is divided into four families: Antarctic cod, plunder fish, Dragonfish and ice fish. There polar fish have become well adapted to cold, their body fluids remain still liquid at temperatures below the freezing point. Their body contain different anti-freeze molecules which impede crystal growth and prevent ice form spreading through the body fluids. Exactly how this works is not yet fully understood."[3]

"The most unusual fish in Antarctic water are the ice fish. They are the only vertebrates whose bodies entirely lack haemoglobin, the red oxygen-carrying pigment in the blood. As they have no haemoglobin, they have only 10% of the normal oxygen-carrying capacity, so they have to compensate with other special adaptations suited to low temperatures. They need less energy to circulate the blood because the viscosity of the blood is lower without haemoglobin. The circulation is even quicken by a larger heart which bears faster. All this makes the transfer of oxygen from blood to tissues more efficient. They also use less energy to maintain their metabolism when resting than red-blooded fish."[3]

Antarctic dragonfishes,

The dominant taxa are the cod icefishes, such as the Antarctic cod.

  1. The Southern Ocean's very cold water allows more oxygen to dissolve in the sea, which is advantageous for marine life.
  2. This, along with the up- welling of currents which bring nutrients from the seabed to feed microscopic algae at the surface, is the key factor of all life in the Southern Ocean.
  3. In this marine food chain, the microscopic algae (or plankton) provide food for krill, which in turn are eaten by fish, whales, seals and birds.
  4. The food web in the Southern Ocean remains remarkably simple when compared with other oceans.[5]

"The cold waters are about four times as productive, acre for acre, as the other oceans of the world. The first link in this immense food chain is the microscopic algae which drift in the ocean and are eaten by zooplankton, of which krill is the most prominent, as well as being the principal food supply for whales. Krill are shrimp-like crustaceans that grow to 7 or 8 centimeters in length, and form enormous schools, which color the sea red. Squid and octopus are also important to the Antarctic ecosystem, providing food for sperm whales, seals, penguins, sea birds, and fishes (see Wildlife Section). It has been estimated that about 55 million tons of squid is consumed annually by the whales of the Southern Hemisphere; this is about 75 percent of the world's current total fisheries catch."[5]

"With the end of the long polar winter comes the arrival of millions of sea birds to breed. Probably 100 million or more birds breed along the coast and offshore islands of Antarctica. Most of the sea birds belong to the species Procellariiformes, which include the albatross (largest flying sea bird, with the wingspan of some species exceeding 4 meters, the fulmers, prions, petrels, and shearwaters. The remaining regular sea bird species encompass shore birds, skuas, gulls, terns, and the penguin."

Seabirds: "While each spring. Around 35 species visit the subantarctic Islands. They range from the magnificent wandering albatross, which flies thousands of kilometres to feed, to gulls, cormorants and terns, which hunt closer inshore. Most return to the same sites each year. Some, like the albatross, mate for life. In addition five species of land birds live all year round on South Georgia, Kerguelen and Marion Islands."[3]

Penguins: "There are 18 species of penguins in the southern water, seven of them live around Antarctica. This flightless birds are found from the equator to the coast of Antarctica. They are well adapted for cold with their dense overall plumage. Best adapted are the emperor penguin, the largest ones."[3]

"Many fish of Antarctica are the only vertebrates that entirely lack red oxygen-carrying pigment (hemoglobin) in their blood. scientists sorting a marine net catchThis adaptation to the cold conditions allows a decrease in blood viscosity and in the amount of energy required to circulate blood. Most research has concentrated on the two most abundant groups: the Antarctic cod Nototheniidae and the ice fish Channichthyidae. Initial interest focused on the evolution of the groups, their ability to survive in icy waters, their reproduction and growth rates and their population age structure. Much current research is concerned with making more accurate estimates of growth and population size."

The Arctic

"The Arctic Ocean is the most extreme ocean on the planet in regards to the seasonality of light and its year-round existing ice cover. The Arctic seas hold a multitude of unique life forms, highly adapted in their life history, ecology and physiology to the extreme and seasonal conditions of their environment. Our knowledge of what currently lives in the Arctic Ocean is still rudimentary compared to other oceans, due to the logistical challenges imposed by its multi-year ice and inhospitable climate."[6]

Arctic Sea Ice

"The Arctic sea ice covers approximately 7x106 km2 in summer and twice that in winter. The unique multi-year sea ice of the deep basins reaches a thickness of 2-3m and allowed the evolution of endemic ice-associated (=sympagic) species, meaning species that are not found anywhere else. Ice organisms live either in the tiny (mostly <1mm in diameter), liquid-filled pores and brine channels within the ice or at the ice-water interface. The biota within the sea ice is consequently small (<1mm) and dominated by bacteria, unicellular plants and animals and small multi-cellular animals (metazoa). Protozoans and metazoans (in particular turbellarians, nematodes, crustaceans and rotifers) can be abundant in all ice types year-round. A partially endemic fauna, comprised mainly of gammaridean amphipods, thrive at the underside of ice floes with up to several 100 individuals m-2. The amphipods are important as the major prey for the Arctic cod (Boreogadus saida), which in turn acts as the major link to seals, birds and whales."[6]

Arctic Pelagic Realm

"Due to their high abundance and ease of capture, the taxonomic composition and life history of the larger more common copepods in the Arctic Ocean was relatively well understood. The same cannot be said for the smallest copepod species that are invariably missed by collection techniques, all deep-water species, and the more fragile gelatinous forms. Although copepods typically predominate, there is a broad assemblage of other planktonic groups in the Arctic that are only occasionally reported in detail."[6]

Arctic fish

"Fish can be found in association with all three Arctic realms described above. Just over 400 fish species are known from Arctic seas and adjacent waters including marine, diadromous (mostly anadromous), and freshwater fish species which enter brackish water. Most of these species are living on or near the bottom. The dominant Arctic fish families are cods, eelpouts, snailfishes, sculpins, and salmonids. One of the key species in the Arctic is the Arctic cod Boreogadus saida, because it is a critical link between lower trophic levels (copepods and under-ice amphipods) and birds, seals, and whales. The Arctic cod is the most northerly distributed gadid, occurring roughly between 60°N and the North Pole, nearshore as well as offshore."

"Unlike most other oceans, commercial fisheries do not exist in the high Arctic, while they are extensive in the sub-Arctic southern Barents and southeastern Bering Seas. The lack of high-Arctic fisheries catch and by-catch data yields a void of even basic knowledge. The traditional methods of collecting fish by trawls do not work well in ice-covered waters, making it difficult even today to advance our understanding of fish biodiversity and biology"[6]

Arctic Benthos

"It is the food supply and not the low water temperatures per se that restrains growth and survival of the seafloor (benthic) animals in the Arctic. On some Arctic continental shelves such as the Chukchi and Bering Seas, the benthos receives large food input from the water column and, therefore, plays a greater role than at lower latitudes. This explains the locally high abundance of bottom-feeding mammals like gray whales and walruses. In contrast, food availability and benthic biomass in the deep Arctic basins are substantially lower than on the shelves."[6]

Census of Marine Life

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Three books released by CoML, 4 October 2010:

  • Discoveries of the Census of Marine Life: Making Ocean Life Count(Cambridge University Press, 304 pages), by Paul V.R. Snelgrove, an overview of Census insights and their implications ([12]);
  • Life in the World's Oceans: Diversity, Distribution, and Abundance(Blackwell Publishing Ltd., 384 pages), Alasdair D. McIntyre (editor), a summary of findings and discoveries by the 17 Census projects ([13])
  • Citizens of the Sea: Wondrous Creatures from the Census of Marine Life,(National Geographic, 216 pages), by Nancy Knowlton, portraits of about 100 species ([14]).

Also released:

  • A National Geographic Society map, depicting the Census' work showing "Ocean Life: Diversity, Distribution, and Abundance" on one side and "Ocean Life: Past, Present and Future" on the other;
  • New scientific reports from the Census of Marine Life added to the new open access Collections and Biodiversity Hub of the Public Library of Science ([15])

See also:

  • Knowlton N (2010) Citizens of the Sea: Wondrous Creatures from the Census of Marine Life, National Geographic Society. ISBN 9781426206436.

Notes

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Shark fishing

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A 14-foot (4.3 m), 1,200-pound (540 kg) tiger shark caught in Kāne‘ohe Bay, Oahu in 1966

It is estimated that 100 million sharks are killed by people every year, due to commercial and recreational fishing.[1][2] Sharks are a common seafood in many places around the world. The meat of dogfishes, smoothhounds, catsharks, makos, porbeagle and also skates and rays are in demand by European consumers.[3] However, the U.S. FDA lists sharks as one of four fish (with swordfish, king mackerel, and tilefish) that children and women who are or may be pregnant should refrain from eating. For details see mercury in fish.

Sharks generally reach sexual maturity slowly and produce very few offspring in comparison to other harvested fish. Harvesting sharks before they reproduce has severe impacts on future populations. Organizations such as the Shark Trust campaign to limit shark fishing. According to Seafood Watch, sharks are currently on the list of fish that American consumers, who are sustainability minded, should avoid.[4]

Overfishing of sharks has led to the upset of entire marine ecosystems.[5]

In 2004, the U.S. National Marine Fisheries Service estimated about 12 million sharks, skates and rays were captured in U.S. waters.[6] About 359,000 were killed and the rest were released back to the sea. For 15 years over a 21-year span, recreational fishermen caught more sharks than commercial fishermen. In California, six tiger sharks were caught recreationally for every one caught commercially.[7]

Threatened species

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In 2009, the International Union for Conservation of Nature (IUCN) produced the first red list for threatened oceanic sharks and rays. They claim that about one third of open ocean sharks and rays are under threat of extinction.[8] There are 64 species of oceanic sharks and rays on the list, including hammerheads, giant devil rays and porbeagle.[9]

Oceanic sharks are captured incidentally by swordfish and tuna high seas fisheries. In the past there were few markets for sharks, which were regarded as worthless bycatch. Now sharks are being increasingly targeted to supply emerging Asian markets, particularly for shark fins, which are used in shark fin soup.[9]

The northwest Atlantic Ocean shark populations are estimated to have declined by 50 percent since the early 1970s. Oceanic sharks are vulnerable because they don't produce many young, and the young can take decades to mature.[9]

See also

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Notes

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References

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  • Shark Depredation and Unwanted Bycatch in Pelagic Longline Fisheries, Blue Ocean Institute, 2007.
  • Dulvy, N.K. and R.E. Forrest. In press. Life histories, population dynamics and extinction risks in chondrichthyans. Chapter 17 In The Biology of Sharks and their Relatives. Volume 2 – Physiological Adaptations, Behavior, Ecology, Conservation and Management of Sharks and Their Relatives. Edited by J. Carrier, J. Musick and M. Heithaus. CRC Press.
  • Forrest, R.E. and C.J. Walters. In press. Estimating thresholds to optimal harvest rate for long-lived, low-fecundity sharks accounting for selectivity and density dependence in recruitment. Canadian Journal of Fisheries & Aquatic Sciences.
  • Clarke, S.C., McAllister, M.K., Milner-Gulland, E.J., Kirkwood, G.P., Michielsens, C.G..J., Agnew, D..J., Pikitch, E. K., Nakano, H., Shivji, M. 2006. Global estimates of shark catches using trade records from commercial markets. Ecology Letters 9: 1-12.
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Workers at a Sturgeon fish market in Türkmenbaşy, Turkmenistan

Five species of fish "Its area is 2000 sq.km and the most depth is about 40 m."[1] It is part of the Aral Sea drainage system[2]


Fishing in New Zealand

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Misc references

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Aquaculture
Recreational Fishing
Fishing industry in New Zealand

Fishing grounds

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Exclusive Economic Zones of New Zealand
 
Sea areas in international rights did not become universally recognized until 1982.
External image
  complex patterns of modern surface currents as warm waters of the Subtropical Gyre and cold Antarctic Circumpolar Current intercept the submarine topography around New Zealand.[3]
Mangroves

New Zealand has mangrove forests extending to around 38°S: the furthest geographical extent on the west coast is Raglan Harbour (37°48′S); on the east coast, Ohiwa Harbour (near Opotiki) is the furthest south that mangroves are found (38°00′S).[4]