Pregnant gray nurse shark (Karchari Vrisha) are wandering away from no-take marine protected areas at night, threatening the extinction of a fierce-looking but mild-mannered species. Not only that, but the critically endangered shark has only about 400 breeding in the wild, according to a 10-year study tracking 34 gray nurse sharks that migrate between the Great Barrier Reef and southern New South Wales (NSW). The people who do are left.
It is commonly known as the ‘grey nurse shark’, ‘spotted tooth shark’ or ‘sand tiger shark’. , [+]
Commonly known as the ‘grey nurse shark,’ ‘spotted ragged-tooth shark,’ or ‘sand tiger shark,’ this species can be found in various parts of the world, including eastern Australia, where they Live in coastal waters, including rocky reefs. coral reefs, and offshore islands. Known to congregate at several sites at “aggregation sites” along the coast of NSW and southern Queensland, they travel hundreds of kilometers between these sites in short periods of time, returning to the same locations in successive years. One of the more distinctive-looking sharks, they are known for their upturned mouth and sharp, jagged teeth, which give them a fierce appearance, despite recorded shark bites in the oceanic continent and generally hostile to humans. Not considered a significant threat unless provoked or cornered. However, this fearsome-looking appearance combined with their large size has caused the eastern Australian population to decline heavily due to overfishing, habitat destruction and the historical misconception that they are dangerous to humans.
Many conservation efforts are being made to protect their habitat, reduce fishing pressure, and raise awareness of the importance of conserving them. But renowned shark activist Valerie Taylor has publicly stated that this is not enough. And this collaborative research, led by Dr Ross Dwyer from the University of the Sunshine Coast and Dr Carley Kilpatrick from the Queensland Parks and Wildlife Service (QPWS), suggests things are more dire than previously thought. Scientists have found that migratory sharks regularly visit no-take MPAs established along Australia’s east coast.
Flat Rock, Henderson Rock, and Cherubs Cave are often frequented by migrating male and female sharks during the winter to early summer. “In contrast, Wolf Rock was particularly important to pregnant female sharks who would remain at the site for up to 254 days during their pregnancies. However, sharks routinely bypass the MPA’s relative safety, often leaving them in the dark,” Dr Dwyer said. Said. “These excursions will increase their risk of becoming bycatch – accidentally entangled in commercial or recreational fisheries or in shark control equipment along beaches.”
Many conservation efforts are being made to protect their habitat, reduce fishing pressure, and , [+]
Kilpatrick explained, “These night-time visits suggest that the existing no-take MPA at Wolf Rock needs to be enlarged to protect the sharks in the areas we now know they use, and for the long-term health of the species.” help ensure protection.” “tracking revealed a longer than expected three-year migratory cycle associated with breeding. This slow breeding rate, until they are at least nine years old and have a maximum of two pups at a time, is sheds light on why the population has been so slow to recover. However, both scientists are concerned that Australia’s no-take MPAs do a great job protecting gray nurse sharks while they congregate in them , they’re spending a lot more time outside of them than they think — including areas around no-take MPAs like Wolf Rock.
The study used a novel combination of the latest animal tracking technology and shark counts for the first time by citizen scientists, said Dwyer: “The study was a largely collaborative effort, and we would like to thank everyone who helped count the sharks.” and helped tag, and maintain more than 300 anchorages along the Australian east coast where these tagged gray nurse sharks were detected – from Heron Island in the Great Barrier Reef to Montague Island in southeast New South Wales. This approach produced accurate, valuable data and can now be applied to other migratory coastal shark species to ensure marine field networks provide maximum protection benefits.
