Description edit
The sandbar shark is one of the largest coastal sharks in the world, and is closely related to the dusky shark, the bignose shark, and the bull shark. Its dorsal fin is triangular and very high, and it has very long pectoral fins. Sandbar sharks usually have heavy-set bodies and rounded snouts that are shorter than the average shark's snout. Its upper teeth have broadly uneven cusps with sharp edges. Its second dorsal fin and anal fin are close to the same height.
Females can grow to 2–2.5 m (6.6–8.2 ft), males up to 1.8 m (5.9 ft). The maximum recorded weight is 240 kg (530 lb). Female sandbar sharks have an average fork-length (tip of the nose to fork in the tail) of 154.9 cm with the males' average fork-length being 151.6 cm. Its body color can vary from a blue-ish brown, grey or bronze, with a white or pale underside. Sandbar sharks swim alone or gather in sex-segregated schools that vary in size.
Maturity and Reproduction edit
There are disagreements about when exactly sandbar sharks reach sexual maturity, but most studies conclude that females reach sexual maturity around 13 years of age, while males tend to reach maturity around age 12 years old[1]. Sandbar sharks are viviparous, with the embryos supported in placental yolk sac inside the mother. Females have been found to exhibit both biennial, consistently reproducing every two years and returning to the same place to have deliver the pup, and triennial, reproducing every three years and returning to the same place for delivery, migration and gestation periods. They also ovulate in early summer, and give birth to an average of eight pups, which they carry for 1 year before giving birth. The longevity of the sandbar shark is typically 35–41 years.
Habitat and Distribution edit
The sandbar shark, true to its nickname, is commonly found over muddy or sandy bottoms in shallow coastal waters such as bays, estuaries, harbors, or the mouths of rivers, but it also swims in deeper waters (200 m or more) as well as intertidal zones.
Sandbar sharks are found in tropical to temperate waters worldwide; in the western Atlantic they range from Massachusetts to Brazil. Juveniles are common to abundant in the lower Chesapeake Bay, and nursery grounds are found from Delaware Bay to South Carolina. Other nursery grounds include Bonjuk Bay in Marmaris, Muğla/Turkey and the Florida Keys.
Predators and Diet edit
Natural predators of the sandbar shark are often tiger sharks, and rarely, great white sharks.
The sandbar shark itself preys on fish, rays, crabs, and molluscs. They have been found to primaily consume osteichthyes, or bony fish, octopi, european squid, and cuttlefish when in areas such as the Mediterranean or the Gulf of Gabés[3]. Sandbar sharks have been described as being a top predator in their ecosystem's food chain[4].
*there is also an image on the wikipedia page itself that is of a sandbar shark that has been caught by fisherman and I chose to move it next to the "human impacts"*
- ^ Romine, J. G., et al. “Compensatory Growth of the Sandbar Shark in the Western North Atlantic Including the Gulf of Mexico.” Marine and Coastal Fisheries, vol. 5, no. 1, Jan. 2013, pp. 189–199, https://doi.org/10.1080/19425120.2013.793631. Accessed 14 July 2019.
- ^ “File:Sandbar Shark Seaworld.jpg - Wikipedia.” Commons.wikimedia.org, 14 Jan. 2007, en.wikipedia.org/wiki/File:Sandbar_shark_seaworld.jpg. Accessed 10 Mar. 2024.
- ^ Saidi, Bechir, et al. "Feeding habits of the sandbar shark Carcharhinus plumbeus (Chondrichthyes: Carcharhinidae) from the Gulf of Gabès, Tunisia." Cahiers de biologie marine48.2 (2007): 139-144.
- ^ Ellis, Julia K., and John A. Musick. "Ontogenetic changes in the diet of the sandbar shark, Carcharhinus plumbeus, in lower Chesapeake Bay and Virginia (USA) coastal waters." Environmental biology of fishes 80 (2007): 51-67.