African penguin

The African penguin, scientifically known as Spheniscus demersus, is a unique seabird. It is the only penguin species found in the Old World. These birds live in the marine habitats of southern African waters. They are flightless birds with streamlined bodies. Their wings are stiff and flattened into flippers for efficient swimming.

This species is also called the Cape penguin or the South African penguin. Because of their loud, donkey-like braying, they are sometimes called jackass penguins. They are highly charismatic animals and are very popular with tourists.

African penguins have several specialized biological adaptations. They use a method called countershading for protection. Their upper parts are black to blend with dark water from above. Their white underparts make them hard to see from below.

They also have supraorbital salt glands located above their eyes. These glands allow them to excrete excess salt from seawater. This helps them maintain osmotic balance while they forage at sea. Additionally, they have pink patches of skin above their eyes. These are actually sweat glands used for cooling. As temperatures rise, increased blood flow makes these glands appear pinker.

Each individual penguin has a unique appearance. They have a black facial mask and a thick black band on their chest. This band often looks like an upside-down horseshoe. The black spots on their white underparts are unique to each bird. These patterns are like human fingerprints.

There is also slight sexual dimorphism in the species. This means males are slightly larger than females and have longer beaks. Juveniles look different from adults. They have dark upperparts that range from greyish-blue to brown. Their pale underparts lack the distinct spots and the black band.

Naturalists have studied these birds for centuries. In 1747, George Edwards described them in his book, *A Natural History of Uncommon Birds*. He used the name "The Black-Footed Penguins." In 1758, Carl Linnaeus placed them in the genus *Diomedea*. Later, Mathurin Jacques Brisson introduced the genus *Spheniscus* in 1760. This name comes from the Ancient Greek word for "wedge." It refers to their thin, wedge-shaped flippers. The specific name *demersus* is Latin for "plunging." This describes their habit of sinking into the water.

These penguins are pursuit divers that forage in the open sea. They eat fish like sardines, anchovies, and mackerels. They also eat squid and small crustaceans like krill.

A penguin may eat up to 10% of its body weight in prey daily. This can increase to 25% when raising older chicks. They perform impressive dives to find food. Most dives reach an average depth of 60 meters. These dives usually last about 69 seconds. However, some dives have reached a depth of 100 meters and lasted 275 seconds.

African penguins are monogamous and breed in large colonies. They nest in burrows made in guano or in sand under bushes.

A pair lays a clutch of two eggs. Both parents share the work of incubation for about 40 days. After hatching, one parent guards the chicks for a month. The chicks then join a group called a crèche.

When it is time to moult, penguins must fast for about three weeks. Their new feathers are not waterproof yet. During this time, they can lose half of their body weight.

The population of African penguins has declined drastically. In the early 19th century, there were roughly 4 million birds. Since pre-industrial times, the population has dropped by 95%. In 2010, the total population was estimated at only 55,000. By 2023, the breeding population fell below 10,000 pairs.

They are now classified as critically endangered. Threats include habitat loss, climate change, and overfishing. To help them, the South African government recently agreed to establish no-fishing zones. These zones will protect six key breeding areas to help the species survive.