Portal:Sharks

The whitetip reef shark, Triaenodon obesus, is a species of requiem shark, family Carcharhinidae, and the only member of its genus. A small shark usually not exceeding 1.6 m (5.2 ft) in length, this species is easily recognizable by its slender body and short but broad head, as well as tubular skin flaps beside the nostrils, oval eyes with vertical pupils, and white-tipped dorsal and caudal fins. One of the most common sharks found on Indo-Pacific coral reefs, the whitetip reef shark occurs as far west as South Africa and as far east as Central America. It is typically found on or near the bottom in clear water, at a depth of 8–40 m (26–131 ft).

During the day, whitetip reef sharks spend much of their time resting inside caves. Unlike other requiem sharks, which rely on ram ventilation and must constantly swim to breathe, this shark can pump water over its gills and lie still on the bottom. At night, whitetip reef sharks emerge to hunt bony fishes, crustaceans, and octopus in groups, their elongate bodies allowing them to force their way into crevices and holes to extract hidden prey. Individual whitetip reef sharks may stay within a particular area of the reef for months to years, time and again returning to the same shelter. This species is viviparous, in which the developing embryos sustained by a placental connection to their mother. One of the few sharks in which mating has been observed in the wild, receptive female whitetip reef sharks are followed by prospective males, who attempt to grasp her pectoral fin and maneuver the two of them into positions suitable for copulation. Females give birth to 1–6 pups every other year, after a gestation period of 10–13 months.

Whitetip reef sharks are rarely aggressive towards humans, though they may investigate swimmers closely. However, spear fishers are at risk of being bitten by one attempting to steal their catch. This species is caught for food, though there are reports of ciguatera poisoning resulting from its consumption. The International Union for Conservation of Nature (IUCN) has assessed the whitetip reef shark as Near Threatened, noting that its numbers are dwindling due to increasing levels of unregulated fishing activity across its range. The slow reproductive rate and limited habitat preferences of this species renders its populations vulnerable to over-exploitation.

• ... that Alexis Sharkey's last Instagram post before her murder documented her travels to Tulum, Mexico?
• ... that since 2018, IKEA's stuffed toy shark Blåhaj has become a popular Internet meme and an icon of the online transgender community?
• ... that "the Hurricane Shark is real"?
• ... that the greeneye spurdog, Sydney skate, grey skate and whitefin swellshark are at risk of extinction by trawling, according to a 2021 report?
• ... that the ampullae of Lorenzini enable sharks to sense electric fields?
• ... that Hixxy and Sharkey created a schism in the UK rave music scene in 1995?

WikiProjects related to sharks:

• WikiProject Science
  • WikiProject Biology
    • WikiProject Tree of Life
      • WikiProject Animals
        • WikiProject Fishes
          • WikiProject Sharks
• WikiProject Aquarium Fishes
• WikiProject Fishing

• ... that male Arabian carpetsharks competing for a mate have been known to bite the claspers of their rivals?
• ... that the porbeagle has been known to "play" with kelp fronds, pieces of wood, and fishing floats?
• ... that the blind shark and the bluegrey carpetshark close their eyes when taken out of the water?
• ... that male Arabian carpetsharks competing for a mate have been known to bite the claspers of their rivals?
• ... that the whitefin, Cook's, Australian reticulate, spotted, leopard-spotted, painted, flagtail, speckled, saddled, and narrowbar swellsharks were all scientifically described in 2008, more than doubling the number of species in the genus Cephaloscyllium?