المواضيع

  The African penguin , also called the black-legged penguin , the head penguin , or the donkey penguin , is a species of penguin characterized by a single strip of black feathers that cuts through the chest and a circle of featherless skin completely surrounding each eye. This species is so named because it lives in several locations along the coasts of Namibia and southern Africa.



Characteristics and shape

African penguins can be 60-68 cm (about 24-27 inches) long and 3.7-4 kg (about 8-9 pounds) in length, with males being slightly larger than females. As in other species, the feathers covering the chin and back are black, and most of the breast feathers are white. African penguins also have prominent C .-shaped areasof white feathers on both sides of the head. By contrast, the feathers on the back and head of juveniles are grey, and those on their underside are white. Chicks are covered with down from gray to grayish-brown feathers.


Predators

Adult and young African penguins are food for tigers and mongooses on land and baby penguins may become victims to cats as well as birds, such as kelp gulls, sacred ibis, and sea snakes. Seals and sharks routinely feed on African penguins.


Reproduction and life cycle

Breeding occurs year-round in colonies located in a chain of 25 rocky islands and a number of mainland sites along the coast of Namibia and the Atlantic coast of South Africa. Peak breeding is between March and May in South Africa and during November and December in Namibia. Monogamy is common, occurring in about 80-90 percent of breeding pairs between one breeding season and another. To attract a mate, both sexes utter a sound similar to the braying of a donkey, which is why they are sometimes referred to as "donkey penguins".

African penguins usually make a depression to lay their eggs in the sand, on bare ground, or under bushes and rocks. The female lays two eggs, which are incubated by the male and female. The incubation period lasts from 38 to 40 days, after which both parents provide the chicks with alternating feeding and guard duties until the chicks are 30 days old. After this period both parents leave the nest to search for food, while the chicks join a "brood" (a group of chicks) to protect against predators. The growth period continues until the chicks are 2-4 months old. After the growth period is over, the young leave the nest to feed alone in the sea. Many African penguins stay away from their original colonies for 1-2 years. Individuals that do not return travel to other colonies to molt and reproduce. African penguins are sexually mature between the ages of two and eight; However, most individuals are able to reproduce by the age of four. The average life span is approximately 10-15 years; However, some sources indicate that African penguins can live from 10 to 27 years in the wild and even longer in captivity.


Save type status

The African penguin population has declined by more than 60 percent since the early 1980s. The blame for these losses lies with the commercial fishing industry, which harvests stingrays  and other shallow fish in the area where the penguins are hunted, but oil pollution and high predation are also significant causes of death. The number of breeding pairs, which exceeded 140,000 pairs in the late 1950s, fell to 69,000 in 1980 and dropped to just over 25,000 by 2009. African penguins are listed as critically endangered on the International Union for Conservation of Nature's Red List. ( IUCN) within the endangered species .

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