NGS stock photo of African penguins by Chris Johns
A colony of African penguins (Spheniscus demersus) living and breeding on a small island off the southern tip of Africa is fighting an increasingly desperate battle for survival. Their numbers are declining drastically despite the care of conservation organizations which have banded together to give them help, even by providing them with nesting homes to shelter them from the sun and to hide their eggs and chicks from sea gulls.
Their plight is typical of the increasingly precarious situation of the species as a whole which last year shifted from Vulnerable to Endangered on the IUCN (World Conservation Union) Red List of Threatened Species.
Responding to the change of status, BirdLife International at the time noted that when the first full census of the species was conducted in 1956, 150,000 pairs were counted. These, it said, were what remained after “more than a century of sustained persecution, principally from egg collecting and guano scraping”.
In 2009, BirdLife said, only 26,000 pairs were counted, representing a loss of more than 80 percent, coming to around 90 birds dying every week since 1956.
The situation is worse on Dyer Island, a low-level rocky outcrop of about 50 acres, or 20 hectares, in a bay near Cape Agulhas. In 1979 it was home to 23,000 pairs of penguins, which amounted to more than half the breeding population along the southwestern coast of South Africa. This year only 900 pairs have been counted. Circling the island by boat, it is countless gulls, but hardly a penguin, you see these days.
Dyer
Island with Geyser Rock on the far side, separated by what is known as
Shark Alley. Picture courtesy Dyer Island Conservation Trust.
In this sad fate of the African penguin, too, it is the hand of humankind that is most heavily evident.
Brenda Walters, operations manager of the Dyer Island Conservation Trust, says guano scraping in the 19th and 20th centuries, for use as agricultural fertilizer, forced penguins to nest on the surface instead of the soft guano burrows they would normally make. The heat stress caused them to abandon their nests, which allowed especially the kelp gulls to get at their eggs and chicks.
- Brenda Walters, Dyer Island Conservation Trust operations manager, with one of the nesting boxes made by the trust. Picture by Leon Marshall.
Government archives show that in the early 1900s nearly 800,000 penguin eggs were removed in just one year, so sought-after they were as a delicacy.
Two major oil spills from ships ten years ago killed many birds. And, as if the human onslaught is not enough, the birds are also vulnerable to the Cape fur seals that abound in the area, having made their home on an outcrop called Geyser Rock that is separated from Dyer Island by a narrow strip of sea named Shark Alley. The seals are kept in check by the great white sharks that regularly cruise through to grab a few, hence the sea strip’s name.
The most basic requirement for the penguin population’s health is that they have enough food. But it is this aspect that is causing most concern. Fish stocks have dropped, but whether by over-fishing or changes in sea conditions possibly brought on by factors like climate change is not clear.
BirdLife International’s assessment last year mentioned commercial fisheries and shifts in prey populations as the likely causes of depleted fish stocks.
Penguins Struggling to Find Food
Rob Crawford, chief scientist for Marine & Coastal Management, the government department responsible for monitoring and protecting seabirds, was quoted as saying: “While it’s difficult to prove exactly what has caused the decreases, all the indications are that the penguins are struggling to find enough sardines and anchovies.”
But limiting fishing in the area is a tricky matter. The nearby coastal village of Gansbaai and adjacent communities have fishing as their main industry. Research into the situation and how to deal with it has been going on for a while.
Walters says tracking data is being obtained to see how far the penguins go for food and the energy they expend in the process. Distances of up to 50 kilometers (31 miles) from Dyer Island have been recorded. The information will help with assessing the need for a marine protected area around the colony.
The trust is playing the key role in trying to rescue the penguin colony. It makes them artificial nests from fiberglass that protect them from the sun and help them defend their eggs and chicks against the gulls. The project has won it a number of environmental awards.
It promotes awareness locally and internationally of the birds’ plight and raises funds mainly through donations made by clients of Dyer Island Cruises, which does cage-dive viewing of sharks and takes tourists on boat trips around Dyer Island. When the penguins go into moult in November, any late chicks are often abandoned. These are removed and taken to rehabilitation facilities. “Every chick counts,” Walters says.
Dyer Island Conservation Trust was set up in 2006 by a colorful local character named Wilfred Chivell who started his tourist-cruise and cage-diving business after losing everything – “company, house, wife” – when his concrete-making business went bankrupt as a result of a serious construction slump.
He designed the fiberglass nests, of which more than 800 have already been installed round the island. Some have also been taken to other breeding colonies.
The
nesting boxes made for the penguins to shelter them from the sun and
marauding sea gulls. Picture courtesy Dyer Island Conservation Trust.
The Trust is the local center for injured and oiled penguins and other seabirds. It is also involved with great white shark research and studies on whales and dolphins, as well as community projects.
Donations can be made by “purchasing” penguin nests on www.dict.org.za. Donors’ names are recorded on the website and they get a certificate of donation.
source
National Geographic Video: Conservationists launch a tracking system to help save the endangered African Penguin:
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