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AFRICAN PENGUIN (Spheniscus demersus)
CLASSIFIED AS ENDANGERED BY THE INTERNATIONAL UNION FOR CONSERVATION OF NATURE
WHERE DO THEY LIVE?
African penguins live mainly on offshore islands along the coast of South Africa and Namibia, and they are the only one of
the 17 penguin species in the world that breeds in Africa. They breed on eight islands and one mainland site in Namibia, 10
islands and 2 mainland sites in the Western Cape, South Africa; and 6 islands in the Eastern Cape South Africa.
WHERE DO THEY BREED?
At most islands where the African penguins breed, the breeding season usually starts in January. The males come ashore and
head back to the same nest site they used the year before. Here they guard their nest site and wait for their partner to
arrive a few days later. Most African Penguins will keep the same breeding partner year after year. They'll lay their first
eggs (usually two) that hatch 38 days later in March. If these parents lose their eggs or chicks, they may lay eggs again
in March/April. If these second clutches also fail or the pair is successful at raising chicks in January, a third clutch
for the season can be laid in May or June. Occasionally the pair will lay again in August or September if they also fail at
the third attempt.
WHAT ARE THE TRENDS IN THE POPULATION?
The overall trend of the African Penguin throughout their distribution is certainly not a very positive one. During the 20th
century the population declined by 90%. While some islands have shown an increase in numbers since the early 1990s, the latest
data shows that the numbers have again nosedived, decreasing by 40%.
Dyer Island is no exception to this trend. In 1956, the year when penguin monitoring in South Africa 'officially' started,
there were an estimated 4000 pairs breeding on the island. In 1979, 22 655 pairs were counted, representing 55% of the
Western Cape's population. Since then however, there has been a steady decline, and in 2007, only 1513 pairs were counted,
a 93% decline in 30 years!
The last count in 2009 showed there were only 1200 remaining breeding pairs!
ARE THEY ENDANDERED?
African Penguins were moved to the Endangered list in May 2010. The IUCN Red List for bird species is revised annually by Birdlife International and the African Penguins rapid decline led to it being moved from Vulnerable to Endangered.
WHAT ARE THE MAIN THREATS THAT THEY FACE?
Historically, the main threats that the penguins faced was hunting, guano scraping and egg collecting.
Although a practise that no longer continues, the guano scraping of the islands from the 1890s still has an impact today.
The penguins used the guano for their nest burrows. Although guano harvesting in South Africa stopped in 1984, the remaining
guano is not deep enough to burrow in, forcing the birds to breed on the surface. Nesting on the surface makes penguins
vulnerable to disturbance, predation and heat stress. When the parents get too hot, they leave the nest to go to sea to cool
down, exposing their eggs and chicks to predation by Kelp Gulls. Where they have dug hollows on the surface, the nests are
flooded which results in loss of eggs and chicks and abandonment of nests.
The main threat that the African penguin currently faces is that of scarcity of food around the colonies. They compete with
commercial fisheries for their main food source (sardine and anchovy). While over-fishing is part of the problem, there has
also been a large eastward shift in the distribution of fish placing the fish out of reach of the breeding birds. Climate
change is expected to exacerbate this situation.
Cape Fur Seals and sharks prey on juvenile and adult penguins, and in some breeding localities they are also preyed on by
dogs and cats. Kelp gulls and cats also prey on eggs and chicks, while Cape Fur seals compete with the penguins for breeding
space.
Marine pollution such as oil spills severely affects penguin populations. South African penguin populations have been impacted
by two large oil spills: the Apollo Sea in 1996, and the Treasure in 2000 which effected the Dassen and Robben island
colonies. Staff on Dyer Island continuously send off oiled birds. This oil is not from grounded tankers however, but from
ships that clean their tanks illegally at sea, or from leaking containers on the sea floor.
Penguins also become entangled in fishing gear and other marine debris.
DO THEY MOVE AROUND?
Adults generally remain within 400km of their breeding locality, and when breeding, stay within 20-40 km of the breeding
colony. Juveniles however move around much further and can move more than 1000 Km from their natal island, usually north
and east of their colony.
AT WHAT AGE DO THEY START BREEDING?
Records have shown that African penguins start breeding from between 2-6 years old, usually at 4 years.
HOW FAR DO THEY TRAVEL IN A DAY TO FEED?
While penguins are incubating or raising chicks, their foraging trips are about 20-40 km from their breeding colony, and
the foraging trip duration is usually between 24 hours and several days each.
HOW FAST DO THEY SWIM?
African Penguins can swim up to 20Km /hr and move at an average of speed of 7 km/hr when travelling.
HOW DEEP CAN THEY DIVE?
African penguins usually dive less than 30m, but deeper dives of up to 180m have been recorded.
CAN YOU TELL THE DIFFERENCE BETWEEN A MALE AND A FEMALE?
Males and females look identical so it is very difficult to tell the difference. Males are generally larger and have bigger
bills, but these differences can usually only be seen when the pair is together.
© 2007 Dyer Island Conservation Trust
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A heavily oiled African Penguin being removed for Rehabilitation at SANCCOB |
African Penguin incubating eggs on nest |
Adult African Penguin guarding two chicks |
Adult African Penguin with a creche of chicks |
African Penguins on Dyer Island |
Oiled African Penguins captured on Dyer Island awaiting transfer to SANCCOB |
The remains of an adult penguin after it has been eaten by a seal |
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