As shoals of
anchovies and sardines have migrated south into cooler waters, the
population of African Penguins that feeds on the fish has plummeted by
90 percent since 2004 along South Africa's west coast, once the
stronghold of Africa's only penguin species.
This
decline, recorded by South Africa's Department of Environmental
Affairs, led to four key fishing grounds being declared off limits seven
years ago in an experiment to see if the measure could help save the
penguins. But scientists are still debating whether fishing has helped
push the species to the brink of extinction.
The debate has gotten
so acrimonious that the Island Closures Task Team, which oversaw the
experiment and determined management actions, disbanded last year.
Meanwhile, the fishing bans remain in place.If effective management of the situation is not carried out, the black-and-white seabirds could soon disappear, experts say.
A Penguin runs out of the ocean after swimming at Boulders beach a popular tourist destination in Simon's Town, South Africa, Thursday, Aug. 27, 2015. The penguins on South Africa's west coast are a big tourist attraction, but their numbers have declined and scientists are still debating whether fishing has helped push the species to the brink of extinction. (AP Photo/Schalk van Zuydam)
In the 1930s, South Africa's largest penguin colony had 1 million African Penguins, and there were many other colonies. Now, only 100,000 of the birds remain in all of South Africa and neighboring Namibia, the only two countries where the species exists. In 2010, the International Union for Conservation of Nature declared the African Penguin endangered.
Relocating penguins to within reach of the masses of anchovies and sardines is only a possibility for chicks — and a difficult one with no guarantee of success.
So, in 2008, the South African government began the experimental ban on fishing in a 20-kilometer (12.4-mile) radius alternating around four key penguin colonies: Robben and Dassen Islands in the Atlantic Ocean and St. Croix and Bird Islands in the Indian Ocean. Some of these waters were hotspots for sardine and anchovy fishing.
A Penguin dives under water in the ocean at Boulders beach, a popular tourist destination in Simon's Town, South Africa, Thursday, Aug. 27, 2015. The penguins on South Africa's west coast are a big tourist attraction, but their numbers have declined and scientists are still debating whether fishing has helped push the species to the brink of extinction. (AP Photo/Schalk van Zuydam)
Recently,
a team led by Janet Coetzee, a fisheries scientist with the Department
of Agriculture, Forestry and Fisheries, was on a small, motorized boat
among dolphins, seals and giant shipping vessels and towing a hefty
oblong device through a banned fishing area. The device determines how
many fish are around. Despite the fish migration, such surveys found
there were plenty of anchovies for penguins during certain months.
Penguin biologists believe that closing areas to fishing leaves more fish for penguins and boosts chick survival by 18 percent.
But
mathematical modelers of fish populations have reservations about that
statistic and insist that the impact of fishing is minimal. Coetzee says
fishing quotas already allow only approximately 10 percent of the
sardine and anchovy population to be taken, leaving plenty of fish for
penguins.
These fisheries experts blame predators like fur seals and sharks, nest flooding, heat stress or disturbances from large fishing vessels for exacerbating the penguin decline — not fishing itself.
Penguin biologists say it's too early to tell.
"These sorts of issues must be teased out and the assumptions clearly understood," said Dr. Rob Crawford, who heads the penguin biologist research. Crawford's team wants to keep the fishing grounds closed for several more years. Fisheries scientists are calling for its end.
The fishing industry is losing its patience and wants to know whether seven years of closures has amounted to anything.
Penguins swim together at Boulders beach a popular tourist destination in Simon's Town, South Africa, Thursday, Aug. 27, 2015. The penguins on South Africa's west coast are a big tourist attraction, but their numbers have declined and scientists are still debating whether fishing has helped push the species to the brink of extinction. (AP Photo/Schalk van Zuydam)
Fishermen follow shoals of fish along the coast. When fishing areas are closed, vessels must take more costly circuitous routes and they suffer losses in catch, said Mike Copeland, strategic project manager for Lucky Star Ltd., a fishing company. An economic analysis of the impact of closures is underway.
"We've been very
puzzled as to why the two parties cannot work together to actually come
up with sound science that shows exactly what's going on," Copeland
said.
An international panel
of experts, called for by the South African government to review the
experimental closing of the fishing grounds and to find a way forward,
met for the first time last year and will reconvene in December.
"There's
a lot at stake," said Ross Wanless, conservation program manager of
BirdLife South Africa, a non-governmental organization that supports
bird conservation efforts. "We need to act now. "
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