![]() ![]() ![]() “If we don’t really substantially start to manage these open-ocean fisheries then we have to start imagining a future where there are oceans that don’t have sharks in them, and then the consequences that come from that.” Will sharks survive? “We’re only starting now to get a hint of the climate change effects on sharks … there will be profound effects. “Fishing is the primary and immediate problem,” he says. ![]() As threats from climate change begin to build, he says it’s even more important to protect shark populations now. Simpfendorfer says the threats to sharks from fishing are now well documented and severe. Because sharks eat smaller fish and take out the weak and injured, they support the integrity of the whole system. Marine scientists say removing top predators from ecosystems can have cascading and hard-to-predict effects on marine food webs. We can now bring some strong science and model the situation (facing sharks) and say that this is the story.” “We just have to keep pushing for science-based fishing limits. She’s concerned they may also be in peril.ĭespite occasionally being “overwhelmed” by the state of the marine ecosystem, she says she’s an optimist. Her particular passion is the world’s 500 species of deepwater sharks that scientists still have much to learn about. With Simpfendorfer and others, Rigby is part of the Global Shark Trends Project that’s working to assess the more than 1,200 species of sharks and rays in the ocean. On Queensland’s coast, peer-reviewed analysis of the state’s coastal shark control program suggests numbers of large sharks, including great whites, tigers and hammerheads, fell by at least 75% over 55 years.Īccording to the latest research in the journal Nature, global action is needed “immediately” to stop shark populations collapsing and “myriad negative consequences for associated economic and ecological systems”.ĭr Cassandra Rigby, a marine scientist also at James Cook University, who has studied sharks for more than 20 years, said: “The implications of removing sharks is an unhealthy marine ecosystem.” What will rapidly falling shark numbers mean?Īs well as sharp falls in the numbers of oceanic sharks, previous research has also found a “pervasive” loss of sharks on tropical reefs, upsetting the ecological balance of these delicate coral-dominated ecosystems. “If the number of sharks stayed the same then we should see a rise in bites. He says with population growth there are more and more people in the water, but this hasn’t translated to more bites. That could be another pointer towards falling shark numbers, says Dr Gavin Naylor, director of the Florida Program for Shark Research at the University of Florida, which maintains a corroborated international file of shark bites on humans. The rise in fatalities, while tragic, was likely down to chance as the number of shark encounters was only slightly above average.Īround the world, the number of people reporting shark bites each year has been falling steadily in recent years. Meanwhile the public’s awareness of sharks is more often piqued not by their conservation plight – or even when they’re unwittingly eating them – but when they bite humans.Īnnual figures showed last week that six of the 10 shark-bite deaths around the world in 2020 occurred in Australian waters. There were signs of hope, the research said, because in places where science-backed controls on shark harvesting existed, numbers were stable or recovering. The group’s findings suggest three-quarters of these open ocean sharks and rays are threatened with extinction and fill in a big section of the jigsaw puzzle of global shark health – a puzzle that’s intrinsically hard to complete. Many of the sharks are important to Australia’s coastal ecosystems, including great whites and the critically endangered scalloped hammerhead which, like other sharks, are still legally fished in Australia. ![]()
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