An U.S.conservation group has pushed a petition to the government requesting that California’s great white sharks should be federally protected as an endangered species. The organization has presented a number of studies and claims, backed by other independent organizations, and argues that California’s white sharks are a genetically distinct species. With a mere 340 adults remaining, it might already be doomed.
“Anywhere in that range presents a very high extinction risk,” says Geoff Shester, the California program director of Oceana, one of the organizations that filed the petition. “It’s well below most other species that are currently listed as endangered.”
Great white sharks have already been listed as vulnerable by the International Union for Conservation of Nature (IUCN), among some other 50 species in the same situation, however the petition filed with the National Marine Fisheries Service says that California’s great whites, which typically dwell in the northeastern Pacific, is a genetically distinct species.
“They’re genetically and behaviorally distinct from other white sharks,” Shester said. “While they are capable of making long-distance migrations, they tend to just go back and forth between the same offshore and coastal sites from year to year. There has been a theory for a while that this population was distinct, but it wasn’t until new science came forward in the last two years that it showed no mixing between this population and the other main ones.”
Worldwide, great whites numbers are dwindling year after year due to a number of factors, from shark finning, to commercial fishing, to bycatch. Pollution is one other major factor which has helped lower the numbers – and in California, at least, great whites were found to be contaminated with high levels of mercury, DDT and PCBs, and no one has figured out why. They’re the most contaminated sharks in the world, according to scientists.
While the ultimate goal of these petitions is to reduce shark mortality, Shester says the first step is to simply gather more data about these little-understood sharks.
“One of the primary outcomes with other Endangered Species Act listings is additional prioritization and funding for research,” he says. “And we really need to understand the trends for this population. We still don’t know some basic biological information.”
Hollywood portrays great whites as vicious, blood thirsty killers, in reality the roles may actually be reversed.
“While we humans tend to be scared of these sharks, these sharks are our allies in the sense that, as top predators, they keep the oceans healthy,” he says. “Just as wolves keep deer populations in check, these white sharks are playing an important ecological role, and they need us to protect them and help them recover.”
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