African Penguin
They are also known as the Cape penguin, and South African penguin, and is a species of penguin confined to southern African waters. It is flightless, with a streamlined body, and wings stiffened and flattened into flippers for a marine habitat. Adults weigh 2.2–3.5 kg and are 60–70 cm tall. It has distinctive pink patches of skin above the eyes and a black facial mask; the body upperparts are black and sharply delineated from the white underparts, which are spotted and marked with a black band. The pink gland above their eyes helps them to cope with changing temperatures.
When the temperature gets hotter, the body of the African penguin sends more blood to these glands to be cooled by the air surrounding it. This then causes the gland to turn a darker shade of pink. The African penguin is a pursuit diver and feeds primarily on fish and squid. Once extremely numerous, the African penguin is declining rapidly due to a combination of several threats and is classified as endangered. It is a charismatic species and is popular with tourists. Other vernacular names of the species include black-footed penguin and jackass penguin, which it is called due to its loud donkey-like bray, although several related species of South American penguins produce the same sound.
Habitat
They are only found on the south-western coast of Africa, living in colonies on 24 islands between Namibia and Algoa Bay, near Port Elizabeth, South Africa. It is the only penguin species that breeds in Africa and its presence gave name to the Penguin Islands. Mainland colonies probably only became possible in recent times due to the reduction of predator numbers, although the Betty's Bay colony has been attacked by leopards. The only other mainland colony is in Namibia, but it is not known when it was established.
Boulders Beach is a tourist attraction, for the beach, swimming and the penguins. The penguins will allow people to approach them as close as a metre. No colonies are known outside the south-western coast of Africa, although vagrants (mostly juveniles) may occasionally be sighted beyond the normal range.
Diet
African penguins forage in the open sea, where they pursue pelagic fish such as sardines and anchovies, and marine invertebrates such as squid and small crustaceans. Penguins normally swim within 20 km of the shore. A penguin may consume up to 540 grams of prey every day, but this may increase to over 1 kg when raising older chicks.
Breeding
The African penguin is monogamous. It breeds in colonies, and pairs return to the same site each year. They have an extended breeding season, with nesting usually peaking from March to May in South Africa, and November and December in Namibia. A clutch of two eggs are laid either in burrows dug in guano, or scrapes in the sand under boulders or bushes. Incubation is undertaken equally by both parents for around 40 days. At least one parent guards the chicks for about one month, whereafter the chicks joins a crèche with other chicks, and both parents head out to sea to forage each day. Chicks fledge at 60 to 130 days, the timing depending on environmental factors such as the quality and availability of food. The fledged chicks then go to sea on their own, where they spend the next one to nearly two years. They then return to their natal colony to molt into adult plumage.
When penguins molt, they are unable to forage as their new feathers are not yet waterproof; therefore, they fast over the entire molting period, which takes around three weeks. Females remain fertile for 10 years. They spend most of their lives at sea until it comes time for them to lay their eggs. Due to the high predation on the mainland, African penguins will seek protection on offshore islands, where they are safer from larger mammals and natural challenges. These penguins usually breed during the winter when temperatures are lower. African penguins often will abandon their eggs if they become overheated in the hot sun. Abandoned eggs do not survive the heat. Ideally, eggs are incubated in a burrow dug into the guano layer, which provides a suitable temperature regulation, but the widespread human removal of guano deposits has rendered this type of nest unfeasible at many colonies. To compensate, penguins dig holes in the sand, breed in the open, or make use of nest boxes if such are provided. The penguins spend three weeks on land to provide for their offspring, after which chicks may be left alone during the day while the parents forage. The chicks are frequently killed by predators or succumb to the hot sun. The eggs are three to four times bigger than hen's eggs. Parents usually feed hatchlings during dusk or dawn.
Population
According to the IUCN Red List they are classed as Endangered(E) and there population trend is currently decreasing. In 2015, the overall number of pairs was about 25,000 pairs, or 50,000 mature individuals. This roughly equates to about 80,000 individuals in adult plumage based on the conversion factor of 3.2 for pairs to individuals . The population in Namibia declined from 12,162 pairs in 1978 to an estimated 5,800 pairs in 2015 which has now probably decreased even more. The South African population declined from 70,000 pairs in 1978/1979 to 19,300 pairs in 2015. Decreases in both countries amount to > 50% in three generations.
Threats
Population declines have been attributed to food shortages resulting from shifts in the distributions of prey species, competition with commercial purse-seine fisheries and environmental fluctuations. Human disturbance and egg-collecting were important factors in the decline of the species in the early 20th century. Egg collection is now illegal, but is still recorded in some areas of the African Penguin’s range. Guano collection was historically a major cause of disturbance at many colonies and the removal of guano deprived penguins of nest-burrowing sites, causing birds to nest on open ground where they are more vulnerable to heat stress resulting in the abandonment of nests, flooding of nests by rain, and increased predation. Both chronic oil pollution and individual large oil spill appear to have long-term significant impacts on colonies. Past mortality from oil spills has been serious and may increase if proposed development of harbours close to colonies proceeds. Most of the population is confined to areas that are near existing or planned major shipping ports . The Cape Fur Seal competes with penguins for food, displaces them from breeding sites and imposes significant mortality at some colonies.
The potential effects of individual storms on breeding colonies at certain sites has been highlighted and, as such, the increased frequency and severity of storms may cause localised losses. In some mainland colonies, predation by mongooses, leopards and caracals, or illegal egg collection may have notable impacts.
Conservation
Conservation Actions Underway
US Endangered Species Act. Continuous monitoring of population trends is carried out at all colonies. In South Africa, most breeding localities are national parks or nature reserves. The colonies at Burghers Walk and Stony Point are in the process of receiving formal protection status. Collection of guano and eggs is prohibited within penguin colonies. The Namibian Islands Marine Protected Area(NIMPA), proclaimed in 2009, protects almost 10,000 km2 of ocean in southern Namibia, including all penguin breeding localities and key foraging habitats. Oiled birds are rehabilitated with success. More than 80% of birds admitted for rehabilitation are returned successfully to the wild. Lost nesting habitat has been augmented using artificial nests at a number of colonies. Some designs have proved successful, increasing breeding success. At other locations, the same designs have not been as successful. The optimal design of artificial nests is currently being researched, with the aim to have suitable nest types for each colony available for testing during the 2017 breeding season. Maintenance of natural breeding habitat takes place where possible. Research into foraging behaviour using biologging technology (GPS and satellite-transmitters) is ongoing. In South Africa, a research project into the potential positive impacts of small marine no-take zones surrounding breeding colonies is underway. Results suggest a decrease in adult foraging effort and increases in chick survival and condition, but not uniformly across the colonies involved. South Africa is in the process of declaring new Marine Protected Areas, including around some seabird colonies. Population reinforcement through hand rearing of abandoned chicks, or chicks removed from nests in compromised areas where survival was unlikely, added 4661 fledglings to the population between 2001 and 2015. These hand-reared fledglings survive and recruit in to breeding populations at similar rates to their wild counterparts . Attempts are made to decrease predation of eggs, chicks and grown birds. A national (South African) capture-mark-recapture programme using Passive Integrated Transponders has been implemented to monitor survival, recruitment and movements amongst colonies.
Conservation Actions Proposed
In South Africa, the African penguin Biodiversity Management plan, gazetted in 2013, is guiding the conservation actions to be implemented. The BMP includes the above actions and identifies additional ones. New actions proposed include: ensuring adequate prey is made available for penguins during the breeding and non-breeding seasons; motivating for spatial management of the pelagic fishery; investigating the feasibility and desirability of and, if deemed viable, developing research projects and strategies to guide conservation translocations in this species, with the aim of establishing new breeding colonies and re-establishing old ones in areas of reliable prey resources ; improving the disaster response to oiling, disease and fire; establish minimum standards for rehabilitation and rehabilitation facilities; improving penguin numbers through targeted interventions at existing but declining breeding localities where the reasons for the decline can be addressed.