The jackass penguin, a flightless seabird, is found nowhere in the world except off the coast of southern Africa, i.e. it is endemic to this area. It breeds on 24 offshore islands between Namibia and Port Elizabeth. Additional colonies were established in the 1980s on the mainland at Betty's Bay and Simonstown. There is also a colony on the mainland of Namibia, although it is not known when this colony was established. Nesting on the mainland is unusual for jackass penguins because they are ground-nesting birds and are vulnerable to the many predators on the mainland.

Jackass penguins used to nest by burrowing into guano (bird droppings which have accumulated into a hardish substance, sometimes several metres deep). Most of the nutrient-rich guano was removed for fertiliser in the 19th century. Penguins now nest in burrows in sand, under overhanging rocks, under bushes, or even in the open. Jackass penguins can breed at any time of the year, usually laying two eggs. Most adult birds feed during the day and the chicks are fed regurgitated food in the late afternoon. The parent birds take turns in guarding the nest site and catching food. Fish eaten include sardine, maasbanker and anchovy. Squid are also eaten.

POPULATION COLLAPSE

The total present population of jackass penguins is about 120 000 birds. In 1930, the total population numbered at least 1,2 million birds. Penguin numbers have therefore decreased by at least 90% in 60 years, and this fall is continuing. Dassen Island, off Yzerfontein, may have once sheltered over 1 million penguins - it now has about 30 000. Dyer Island, near Gaansbaai, now has about 20 000 penguins. The largest colony at present is St. Croix Island near Port Elizabeth, with about 50 000 penguins.

THREATS TO PENGUINS

The collapse of the jackass penguin population this century has been a result of the following:

* Harvesting of eggs for human consumption.

* Reduction of the penguin's food supply by commercial fishing.

* Oil pollution from oil tankers. This could devastate the major colonies. Oil tankers may illegally clean out their tanks as they pass round the Cape to fill up with oil in the middle east.

* Large-scale removal of guano in the 19th century has decreased the ability of penguins to construct nests through burrowing. This has led to increased competition for breeding space with larger animals such as seals. Penguins breeding on the mainland are vulnerable to mainland predators not found on islands, such as leopards, genets and domestic dogs and cats, and also to human disturbance unless the colonies are adequately fenced and patrolled.

CONSERVATION ACTION

All the islands where jackass penguins breed, except Robben Island, are protected as provincial nature reserves or fall within the West Coast National Park.
However, there is competition with seals for the limited breeding space available on some islands, and some individual seals are known to kill and eat penguins. At Mercury Island seals have been successfully displaced from penguin breeding sites. At Dassen and Robben Islands steps have been taken to eliminate the feral cat populations.

Efforts have been made to protect the new mainland breeding colonies at Betty's Bay and Simonstown. A 100-metre fence has been erected at Stony Point peninsula at Betty's Bay, and this is successfully preventing human disturbance and attacks by predators. The colony has grown to more than 100 nesting pairs.

The South African National Foundation for the Conservation of Coastal Birds (SANCCOB) carries out valuable work in rescuing oil-soaked penguins (and other seabirds) and rehabilitating them back to the wild. SANCCOB has one of the world's highest rates of success in saving oiled seabirds, primarily because penguins respond better to captivity and cleaning than do flying birds.

WHAT YOU CAN DO

* Support SANCCOB as a volunteer, cleaning and feeding oil- soaked or injured penguins and other seabirds.

* Take oiled or injured penguins or seabirds to SANCCOB.

* Support SANCCOB by raising money for their work.

DID YOU KNOW?

* Jackass penguins are fast swimmers with an average speed of about 7 km\hour.

* Jackass penguins are efficient navigators. One oiled penguin which was rescued, cleaned and released on Robben Island in August 1971, travelled 800 km to Port Elizabeth within a month.

FURTHER READING

ROBERTS' BIRDS OF SOUTHERN AFRICA. G.L. Maclean. John Voelcker Bird Fund, Cape Town, 1985.

OCEANS OF LIFE OFF SOUTHERN AFRICA. A. Payne and R. Crawford (eds). Vlaeberg Publishers, Cape Town, 1989.

SECRETS OF THE SEAS. Illustrated guide to marine life off southern Africa. A. Payne and R. Crawford (eds). Vlaeberg Publishers, Cape Town, 1992.

All books are available from Russel Friedman Books, PO Box 73, Halfway House 1685. Tel. 011-7022300/1.

USEFUL CONTACTS

SANCCOB (South African National Foundation for the Conservation of Coastal Birds). Cape Town, PO Box 11-116, Bloubergrant, 7443. Tel. 021-5576155.

Dept. Environment and Cultural Affairs (previously Cape Nature Conservation) P/Bag X9086, Cape Town, 8000. Tel. 021-483 4227.

National Parks Board. PO Box 7400, Roggebaai, 8012. Tel. 021-222816.

Dept. Environment Affairs and Tourism: Sea Fisheries Research Institute. P/Bag X2, Roggebaai, 8012. Tel. 021-402 3911.