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Shark Mystery: Where Have South Africa’s Great Whites Gone?

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A great white shark off Cape Town leaps in pursuit of a fur seal. CHRIS FALLOWS

The world’s most famous sharks are the great whites off Cape Town, featured in the popular “Air Jaws” series. But now these sharks have mostly gone missing, and some experts blame a fishery for depleting the smaller sharks that the great whites feed on.

It’s a shimmering early morning in False Bay, a shallow, 18-mile-wide basin on the southwest corner of South Africa. A small boat with a dozen tourists sways rhythmically in the swell just downwind of Seal Island, a strip of rock that barely clears the water and is covered with thousands of breeding Cape fur seals and tens of thousands of seabirds. The animals’ waste saturates the breeze with sharp-smelling ammonia, and a light veil of winter air pollution hangs over the city of Cape Town, which lies just to the north.

Suddenly and almost silently, a gusher of white water explodes from the sea 100 yards from the boat. The tourists glimpse a muddled flash of fins and a massive tail whipping around inside the crown of flying foam. The seething water flattens, and seconds later the gasping snout of a wounded seal breaks the surface. The unmistakable dorsal fin of a large great white shark comes up straight and steady behind it, and the seal is taken down in the giant fish’s jaws.

Since 1996, Chris Fallows has made a good living taking thousands of tourists and dozens of film crews into False Bay to witness extraordinary sights like this, either from the deck of his boat or from an underwater cage held alongside. Great white sharks congregate around Seal Island in the southern winter to feed on newly weaned Cape fur seals, which take their first, naive swims at this time of year. The white sharks here are noted for their breach kills; starting at depth, they swim rapidly upward and hit shallow-swimming seals from below. The sharks’ momentum carries them in the air, which makes for the spectacular images in the Air Jaws series of documentary films — largely hosted by Fallows — that have had billions of views on the Discovery Channel since 2001.

“The flying sharks of False Bay are now the most famous sharks in the world,” he says.

Sightings of aerial attacks by sharks have dropped from a peak of 11 per trip in 2004 to 0.3 per trip today.

It’s become increasingly rare, though, to witness these remarkable kills, particularly in the last two years. For more than two decades, Fallows has been keeping records of kills and attempted kills by sharks seen from his boat in False Bay. These sightings have dropped from a peak average of more than 11 events per trip in 2004 to around 0.3 events per trip in 2017 and this year. Other shark tourism operators and scientists have noted a similar change in the world’s best-known shark hunting ground and for at least a hundred miles to the east. The question now is, what has happened to the sharks?

Fallows and his colleagues in South Africa’s shark tourism business think they have the answer. The culprit, they believe, is a long-line fishery that has been targeting smaller species of sharks, including soupfin and smooth-hound sharks, which are a favored prey species of great whites. The South African government has encouraged this poorly regulated fishery and has granted licenses to politically connected boat owners, whose catch is often sold to Australia, where it winds up in fish ’n chips.

Since 2013, about three to six demersal longliners — fishing boats that set lines with up to 2,000 baited hooks on or near the sea floor — have been working hundreds of miles of the southern coast of South Africa. Fallows says these boats have intensified their efforts in recent years and have driven stocks of smaller shark species to collapse, which may have led to starvation of juvenile great whites and driven other great whites elsewhere. The fishery may also be illegally hooking and killing young great whites and protected hammerhead sharks, he believes.

A fur seal colony in False Bay. When seals are unavailable, great whites prey upon smaller species of sharks. ADAM WELZ

While noting the decline in False Bay and other areas, some South African scientists say they still have not determined the cause. Other possibilities, these scientists say, are that pods of killer whales — which feed on great white sharks — are more active in the area, driving the great whites elsewhere. Changing ocean conditions, some experts say, could also be forcing great white sharks to search for new hunting grounds.

“There could be some shift in the environment happening,” says Meaghen McCord, founding director of the South African Shark Conservancy. “We’re just not sure, and with us being on the cusp of possible large climate-related shifts, few scientists are prepared to say anything conclusive just yet.”

One scientist says that the longline shark fishermen are “targeting great white food left, right and center.”

Marine biologist Sara Andreotti, a postdoctoral researcher at Stellenbosch University, led a study that estimated the total South African population of great whites at only between 353 and 522 individuals in 2011 – making them far more scarce than the country’s well-known rhinos. She cautions that pointing to orcas and undefined environmental changes can move the focus from overfishing by “shifting the blame onto something we don’t have control upon.” Andreotti says that fishermen are “targeting great white food left, right, and center.” She’s concerned that observations by shark tourism operators – who spend more time on the water than most scientists – indicate a sharp population decline since her study was completed, but says no peer-reviewed data is yet available to confirm such a drop.  

 “I’m angry and desperate,” says Wilfred Chivell, who owns a large cage-diving ecotourism company in the epicenter of shark-watching, Gansbaai (“Goose Bay”, in Afrikaans), about 30 miles east of False Bay. He says that sightings of white sharks have declined sharply in his area, too, and that local fishermen complain to him that demersal longliners have wiped out the bronze whaler sharks they used to catch by handline from small boats offshore. Chivell says he has had to pay the locals not to catch the remaining bronze whalers close to shore so he can have something to show his clients when great whites are absent.  

 In 1991, South Africa became the first country to grant legal protection to great white sharks, and since then shark viewing and cage diving have become a major tourist industry along its southern coast, hosting more than 80,000 visitors a year and helping to contribute tens of millions of dollars to the economy. Many shark conservation organizations are active here, sharks are often portrayed positively in the local media, and many visitors doubtless leave with the impression that South Africa is serious about shark conservation.  

Most sharks are vulnerable to overfishing because they have few young, mature slowly, and live a long time (soupfin sharks can live to 55). Shark populations usually recover from decline far more slowly than most bony fishes, over decades rather than years. Given this, and the pivotal ecological role sharks play as top predators, Chivell believes the government needs to put an immediate moratorium on shark demersal longlining, “because in a year’s time it might be too late.”  

The South African fishing industry has been beset by allegations of high-level corruption for years.

South Africa’s fisheries are largely regulated by the Department of Agriculture, Forestry, and Fisheries (DAFF), which gathers data on fish catches and populations and grants fishing rights to individuals and companies that conform to certain requirements, such as owning appropriate boats or belonging to race groups that were disadvantaged under the apartheid regime. DAFF scientists analyze data to make catch size recommendations for different species, but DAFF managers (many of whom are not scientists) ultimately determine fishing permit conditions and grant fishing rights based on a number of considerations, many of which are political.  

In 2014 the government launched Operation Phakisa, a drive to “grow the ocean economy” and help reduce the country’s shockingly high unemployment rate by creating a million new jobs. Employees at environmental non-profits say that DAFF management is now under immense pressure to be seen creating jobs. The South African fishing industry has been beset by allegations of high-level corruption for years; many of the biggest players in scandals linked to the current ruling party have roots in fishing.

A 2014 government-commissioned investigation into fishing permit irregularities found that at least three participants in the demersal shark longline fishery had obtained rights without having the required shark-fishing boats. Imraan “Imie” Patel — head of Letap Fishing CC — somehow got a shark permit with a squid-fishing boat. Another influential player in the sector, Sharmilla van Heerden of Fisherman Fresh, has multiple boats and touts her relationships with DAFF officials. 

Fallows and Chivell do not have conclusive evidence that soupfin and smooth-hound shark populations have collapsed or that demersal longliners are to blame, because they have not been given access to DAFF’s catch data and DAFF scientists have yet to complete current stock assessments for these species. But they say that DAFF’s data must show that stocks of these sharks are in trouble; a presentation about fishing rights given by DAFF officials to coastal communities in June includes a graph showing smooth-hound and soupfin sharks as “under heavy fishing pressure” and soupfin sharks as “depleted.” DAFF did not respond to requests for comment for this article or provide Yale Environment 360 with recent data on shark catches.

Some experts believe South Africa’s great white sharks are in trouble because longline fishing boats are decimating smaller sharks, a favorite prey species. ISABEL SOMMERFELD/FLICKR

A research program led by shark researcher Matt Dicken has tagged 674 smooth-hound sharks in the port of Coega, about 500 miles east of False Bay. Dicken says that of the 9 tags reported outside the port, seven were from sharks caught by demersal shark longliners. Unpublished data from an acoustic tagging program that tracks fish along the South African coast suggests high mortality rates among young hammerhead and bronze whaler sharks.

Chris Fallows has documented dramatic drops in young hammerhead sharks in a nursery site on the south coast. Although hammerheads are strictly protected, he says it’s likely they’re being caught by demersal longliners, which are active in the area.

WWF-South Africa also has raised red flags about shark fishing via its South African Sustainable Seafood Initiative (SASSI), which scientifically assesses available data and ranks species as green (well-managed), orange (consume with caution) and red (do not buy) to encourage consumers to buy fish from well-managed stocks. In 2015, SASSI ranked soupfin and common smooth-hound sharks as red species owing to a lack of data about stocks and indications that they may be overfished.

“We operate according to the precautionary principle” says Pavitray Pillay, manager of SASSI. “We need evidence that the stock is healthy,” she says, and the government has not provided data to confirm this. “The latest stock assessment for soupfin sharks was done in back in 2005”, she says, adding that “DAFF is in institutional meltdown at the moment,” its leadership compromised by allegations of high-level corruption. The current minister of DAFF and the deputy director-general in charge of fisheries are reportedly under investigation for taking bribes from an abalone kingpin. Some of the bribe money was allegedly destined for former president Jacob Zuma.

Pillay says that South Africa’s demersal shark longline fishery is legally constrained by Total Allowable Effort (TAE), not Total Allowable Catch (TAC), meaning that the number of permitted boats is limited but the number of sharks caught is not. There is therefore no upper limit on the sharks that rights-holders can kill. None of the demersal shark longliners have independent observers on board to check if non-target or protected species are being taken illegally and perhaps being transferred to other boats at sea to evade shore-based inspectors.

Almost all the shark caught in South Africa is exported, with much of it going to Australia where it is used in fish and chips.

Analysts at TRAFFIC, which monitors the global wildlife trade, have found that almost all the sharks caught in South Africa are exported, Australia being the largest market. Shark meat is usually sold as “flake” and made into fish ’n chips. Australian authorities have recommended that only Australian-caught gummy sharks and rig sharks from New Zealand should be labeled as “flake,” but this is not legally binding.

“We certainly have issues with mislabelling of all manner of shark species as ‘flake’ in Australia”, says Adrian Meder of the Australian Marine Conservation Society, which publishes the Australian equivalent of the SASSI list. He says that soupfin shark — known as school shark in Australia — is “woefully overfished” in Australia. “Given the experience here and elsewhere, there’s a strong case that species like the school shark should not, given their biology, be considered a fishery species,” he says. The fins of South African sharks also are sold into the Asian market to be used in shark fin soup.

Not all observers are sure that overfishing of smaller shark species is what is causing white shark populations to move or collapse. Researchers have recorded an increasing number of killer whales, or orcas, moving in the False Bay and Gansbaai areas in the last decade, and white sharks tend to leave the immediate areas around orca pods, at least temporarily. One recent report said that orcas had killed three great white sharks in the Gansbaai area, thus driving the sharks to other areas. Some observers have anecdotally noted an increasing number of shark sightings east of False Bay and Gansbaai, which might indicate a movement in the population, not necessarily an overall reduction, although these sightings have not been rigorously documented or scientifically analyzed.

“This very small fishery has a very large chance of destroying our coast for generations to come,” says one expert.

The lack of hard scientific evidence that the demersal longline fishery is causing a collapse of the South African white shark population does not deter Fallows from his conviction that the fishery must be curtailed as soon as possible. He and others argue that the shark-watching industry generates far more income and employment than a few longline boats and cannot be risked for so little potential gain — not to speak of the handline and shore-based fishers who will lose out if smaller sharks vanish.

“I’ve been on the ocean for most of my adult life,” he says. “This very small fishery has a very large chance of destroying our coast for generations to come. They say that it’s up to us to prove that the fishery is wiping out sharks. We say that the onus is on them to prove that it’s not.”

See original article: https://e360.yale.edu/features/shark-mystery-where-have-south-africas-great-whites-gone

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