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.
* 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.
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.
* Take oiled or injured penguins or seabirds to SANCCOB.
* Support SANCCOB by raising money for their work.
* 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.
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.
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.