A new study suggests that human activities, such as shark control programs and bycatch, may be having a greater impact on white shark populations off the coast of South Africa than killer whales, leading to a potential decline in the species.
Off the coast of South Africa , near the fishing town of Gansbaai, two orcas have made a name for themselves worldwide.There's just one problem, a new paper lays out. The orcas aren't the real culprit. Rather, an even more efficient predator could be driving sharks from their home: us.
In recent years, it has begun to emerge that killer whales are highly skilled hunters of sharks, including large species such asa shark's body, targeting the liver – rich in lipids that sustain sharks on long migrations – and extracting it with near-surgical precision.there were 11 documented occurrences of orca predation on white sharks, mostly wash-up carcasses, thought to be the work of Port and Starboard It's impossible to tell how many sharks Port and Starboard kill each year on average, since we can't be sure humans always record the hunts. However, according to a paper led by marine biologist Enrico Gennari of the Oceans Research Institute in South Africa, humans likely have the killer whales beat hand over fist. He and his colleagues drew on multiple lines of evidence to estimate the anthropogenic white shark death toll among the South African population, and the numbers are far higher than known orca kills. Humans, they find, are removing an estimated 44 white sharks per year from coastal South Africa through the KwaZulu-Natal shark control program and as bycatch ofHowever, exactly what those white shark populations are doing has been the subject of debate. A 2023 study suggested the sharks have not declined, but insteadin their opinion piece that the broader evidence is more concerning. The white shark population is not stable, they say, but declining. And this has graver implications for the species globally. "If the worrying declines observed in what were once considered the largest aggregation sites of white sharks in the world, in just less than a 15 yr period, were representative of the entire population of white sharks in southern Africa, as we believe they are,"The most recent count of white shark numbers used data up to 2011 and estimated that the population swam atNo census has been taken since then – and sightings of the animals have fallen dramatically in some places.between 2000 and 2015. Between 2016 and 2020, that rate dropped to 0.3 sharks per hour. By 2018, the number was Gennari and colleagues are likewise concerned that the white shark population is in decline. They estimate that the 44 white sharks killed each year, through the demersal shark longline fishery regulated by the South African government and the KZNSB shark control program, amount to around 5 to 10 percent of the estimated population yearly. That's unsustainable on its own, and it's not even accounting for other sources of human-caused mortality not included in the estimate.We can't control what Port and Starboard do, obviously – but that, the researchers say, makes it even more important to impose limits on human activity that "Predation by orcas is a natural phenomenon that, no matter the level, does not fall under management control of the government of South Africa, similarly to other sources of mortality occurring in international waters," "However, the ongoing mortality of white sharks from the DSL and KZNSB, which do fall under government regulation, alone at levels sufficient to prevent white shark recovery, and likely to drive its decline."
Sharks Killer Whales Conservation South Africa Human Impact
United States Latest News, United States Headlines
Similar News:You can also read news stories similar to this one that we have collected from other news sources.
On’s Second CEO Change in a Year Could Indicate Bigger Issues at the CompanyAnalysts and Wall Street react after On Holding announced an update to its top CEO leadership structure on Wednesday, its second in one year.
Read more »
AI can help us thrive, but humans still need humans.70 years of research, from Harlow's monkeys to today, tells us what AI can't replace.
Read more »
Reds Opening Day to bring near-record warmth, bigger concern after with storm threatA cold front is expected to trigger rain and storms late Thursday night into early Friday morning.
Read more »
Humans Were Already Dog People 16,000 Years Ago, DNA SuggestsSome bones indicate that the hunter-gatherers of the time fed dogs fish. Their remains were also treated in similar ways to those of humans in death.
Read more »
OP-ED: Threat to package delivery workers is threat to communitiesCity Council is considering legislation that would change relationships between large delivery companies and the independent operators.
Read more »
Black flies plague SoCal community — painful bites around eyes and neck reported for humans and animalsToday's Video Headlines: 03/26/26
Read more »