Off SA’S coast
Gennari, Neil Hammerschlag and
This fishery is conservatively estimated to have killed an average of 40 white sharks a year, mainly from 2008 to 2019. Photographer Oliver Godfrey observed three white sharks being caught and killed by this fishery while he was on one of its boats. He confirmed dead white sharks were discarded at sea and not reported to authorities.
Three white sharks killed in 10 weeks by one vessel equates to 40 white sharks killed by an average of four vessels operating for only three weeks per month, 10 months of a year (all conservative figures).
Nevertheless, South Africa’s Department of Forestry, Fisheries and the Environment has no official records of any of those because it relies only on the records supplied by the same fishery. The lack of records should raise concerns in the department as it knows that during a test run of this fishery, its scientists set three longlines, caught two white sharks and killed one.
What’s in dispute
A recent study claimed that the population of white sharks in South Africa was stable. The study suggested that the sharks had simply relocated eastwards, fleeing from a pair of shark-eating orcas. According to the authors of the study, the stability of the white shark population was “encouraging” and “reassuring”.
But our review of that study found that its authors’ results could not demonstrate a stable white shark population, nor that the sharks had relocated. Our analysis found several discrepancies between the results and conclusions.
The main discrepancies included that the decline of white sharks in the Western Cape began before the appearance of the shark-eating orcas in 2015 as reported. And at present there is no evidence of any location with the same large numbers of white
shark comparable to the numbers found 10 to 15 years ago in the Western Cape. If the sharks had only relocated, their numbers should be found elsewhere.
There have been only eight confirmed white shark deaths by orcas since 2017, but possibly a few more went unrecorded. Nevertheless, the permitted nets, drumline and longline fishery have together probably been responsible for at least eight times more white shark deaths, every single year.
Next steps
South Africa is still permitting unsustainable shark fishing operations in its waters. This ought to stop.
We also advocate a discussion on new approaches to bather safety that don’t kill sharks, as also advocated in Australia. Tethered drones, shark spotters and “smart drumlines” that send alerts to quick response teams when sharks are caught are among available technologies to protect swimmers and surfers without culling sharks.
Enrico Gennari is a research associate at the Department of Ichthyology and Fisheries Science and a shark scientist at Rhodes University, and the founder of the Oceans Research Institute in Mossel Bay; Neil Hammerschlag is a courtesy faculty member at Oregon State University and a member of the Fisheries, Wildlife and Conservation Sciences Department at the University of Oregon; Sara Andreotti is a postdoctoral researcher in management and conservation of white sharks at Stellenbosch University.