The Isabela oriole (Oriolus isabellae) is a species of the oriole family endemic to Luzon in the Philippines. The bird was presumed to be extinct for many years until its rediscovery in December 1993 near Diffun, Quirino,[2] and in Mansarong in September 1994.[3] Additional sightings were made in San Mariano, Isabela. and Baggao, Cagayan Valley[4] It It is found in moist lowland forest up to 440 masl. It is threatened by habitat loss and hunting.

Isabela oriole
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Oriolidae
Genus: Oriolus
Species:
O. isabellae
Binomial name
Oriolus isabellae
Map of the Northern Philippines showing known locations of sightings or collections of the Isabela oriole
Known locations of sightings or collections

Taxonomy and systematics edit

The Isabela oriole is commonly confused with the much more common white-lored orioles and black-naped orioles. It is differentiated by its extremely large bill grey bill, uniform olive-yellow plumage and lack of white on its lores.

The Isabela oriole is most closely related to the white-lored oriole. Both species are closely related to the paraphyletic Philippine oriole.[5] The Isabela oriole is sometimes considered to form a superspecies with the dark-throated oriole and the Philippine oriole.[6] Alternate names for the Isabela oriole include the green-lored oriole and olive-lored oriole.

Distribution and habitat edit

The Isabela oriole is now confined to the lowland forests in the Northern Sierra Madre mountain range in Luzon.[7] It is frequently seen in the canopy and middle storeys of forests and also forest edge or patches up to 440 masl. It is seen in mixed flocks with other birds such as bar-bellied cuckooshrikes, black-and-white trillers, blackish cuckooshrikes and other forest birds.

It has not been recorded in Bataan province since 1947 despite an intensive search done in 2014.[1]

Conservation status edit

The Isabela oriole has a known population of about 50-250 mature individuals and is assessed as Critically Endangered based on its extremely small and fragmented population.[1] Organisations such as Buhay-Ilang and the Mabuwaya Foundation are working to conserve them with educational programs and festivals celebrating this bird. The oriole is now a Flagship species for the North Sierra Madre National Park.

Since 2015, a research and conservation project for the Isabela Oriole has been implemented in Baggao by the Mabuwaya Foundation. Information, education and communication, community consultations are held in Baggao with the local government, the Department of Environment and Natural Resources and local residents. Plans are underway to declare the oriole site in Baggao a Critical Habitat and to encourage ecotourism.[8]

References edit

  1. ^ a b c BirdLife International (2018). "Oriolus isabellae". IUCN Red List of Threatened Species. 2018: e.T22706378A134213171. doi:10.2305/IUCN.UK.2018-2.RLTS.T22706378A134213171.en. Retrieved 12 November 2021.
  2. ^ Gamauf, Anita; Tebbich, Sabine (February 1996). "Re-discovery of the Isabela Oriole, Oriolus isabellae" (PDF). Forktail. 11: 170–171. ISSN 0950-1746.
  3. ^ van der Linde, K. (1996). "A further record of the Isabela oriole (Oriolus isabellae) from Baggao, Cagayan Province, northern Philippines." Forktail 11: 171.
  4. ^ van Weerd, M. and Hutchinson, R. (2004) "Observations of Isabela Oriole Oriolus isabellae in the Sierra Madre, Luzon, Philippines, with descriptions of the call." Forktail 20: 133-136. [1] Archived 2012-04-14 at the Wayback Machine
  5. ^ Knud A. Jønsson, Rauri C. K. Bowie, Robert G. Moyle, Martin Irestedt, Les Christidis, Janette A. Norman, Jon Fjeldså (2010) Phylogeny and biogeography of Oriolidae (Aves: Passeriformes) Ecography 33(2): 232–241 doi:10.1111/j.1600-0587.2010.06167.x
  6. ^ "Dark-throated Oriole (Oriolus xanthonotus)". www.hbw.com. Retrieved 2017-02-24.
  7. ^ "Oriolus isabellae - Avibase". avibase.bsc-eoc.org. Retrieved 2017-02-25.
  8. ^ International), BirdLife International (BirdLife (2018-08-20). "IUCN Red List of Threatened Species: Oriolus isabellae". IUCN Red List of Threatened Species. Retrieved 2021-09-04.