Wednesday 26 February 2014

Facts about the African Penguin


 African penguins, Boulders Beach, South Africa- by
Author Paul Mannix
Creative Commons Attribution 2.0 Generic license.

African penguins (Spheniscus demersus) are sometimes called Blackfoot penguins or because of the braying noise they make during the courtship of a mate they are sometimes called Jackass Penguins. They are not as well studied as other penguin species and information on their habits and breeding can be in complete.

They live and breed on islands off the southwest African coast bathed in the cold, nutrient rich, stream of the Benguela current. African penguins are the only species of penguin that breeds and lives in Africa in the wild and found nowhere else. They are one of the group of Banded penguins (Spheniscus) along with Galapagos, Humboldt, and Magellanic penguins with an estimated population of 180,000.

Description


Africans have white fronts and black backs. They have a black chin with a patch on their face that separates it from the crown of their head by a white band. A narrow black stripe runs across their white breast and down their flanks and down to its legs.

Some Africans, but not all, have a double bar on the chest and throat similar to a Magellanic penguin. Male Africans have heavier beaks and tend to be greater in size than females. They are very similar and the differences tend only to be noticed when they are standing near each other.

Adolescents, unlike adults, are bluish grey and the white face markings and black stripe around the front is absent. Juveniles differ from adults by being entirely blue-grey above, and lacking the white face markings and black breast band of the adults. Their bodies are streamlined and their short wings act as flippers propelling them through the water at up to 20 mile per hour. Africans stand at about 18 inches tall and weighing about 7.5 pounds they are not as big as Emperor, King or Yellow-eyed penguins but greater than Little Blues.

Hunting and Diet


African penguins have been seen at sea as far as 60 miles from land. Usually they hunt near rocky coasts for fish such as pilchards or anchovies or for crustaceans such as krill and will eat up to one pound of food daily.

As with other species of penguins Africans often take to the water in a group and have a tendency to hesitate before jumping into the sea. Usually one will take the plunge first and the others will follow en masse possibly to distract, or confuse any waiting predators.

Breeding


In September and February they form breeding colonies, or ‘rookeries’ where they will build nests. These are often shallow burrows in sand, bare ground or under rocks, sparse vegetation, or even guano. There needs to be sufficient cover to protect eggs and adults from the heat of the African climate. The female lays two green eggs which need incubating for about five weeks and both parents share this duty. They will also share the care of the chicks when they hatch in about 5 five weeks time.

Predators and Threats


On land the chicks and eggs may fall victim to Kelp gulls, skuas and Ibis. In the sea they are preyed upon by sharks and Fur seals. Scientists are concerned that their population is fast declining. In the past they have suffered from oils spills, loss of habitat and human activity such as overfishing. They increasingly have to compete with seals for dwindling stocks of food and diminishing breeding grounds. African penguins are listed as ‘Vulnerable‘ (A2ace+3ce+4ace ver. 3.1 (2008)) on the IUCN Red List.

References, Attributions and Further Reading

This article was orginally published on Helium.com on and  updated October 10, 2009 by zteve t evans.  In November 2013 Helium.com became Critters 360 and a version remains on there.

Image - File:A pair of African penguins, Boulders Beach, South Africa.jpg - From Wikimedia Commons - African penguins, Boulders Beach, South Africa- by AuthorPaul Mannix Creative Commons Attribution 2.0 Generic license.

The International Penguin Conservation Working Group

MarineBio Conservation Society

African Penguin from Wikipedia


Tuesday 25 February 2014

Facts about the Humboldt Penguin



 Humboldt Penguins, Islas Ballestas, Paracas, Peru
Image Author Lisa Weichel  

Humboldt penguins (Spheniscus humboldti) are sometimes known as Peruvian penguins. They are located only along the Pacific coastline of South America. They are warm weather penguins preferring islands or rocky shores to form breeding colonies on. They range from Isla Foca off the coast of Peru to Algarrobo in Chile and have remote colonies to the south on the Punihuil Islands.

Humboldt penguins are members of the Banded penguin group (Spheniscus genus) along with African, Magellanic, and Galapagos penguins. They are named after the Humboldt Current that brings nutrient rich cold water to the ocean along the Pacific coast of South America past Chile and Peru before turning westwards. Humboldts do not migrate preferring to stay in these regions all year round.

Description 


Humboldts look very similar to Magellanic penguins and it is often the case that their colonies overlap and both birds can be wrongly identified very easily. There are differences that a practiced eye may spot. Humboldts have one neck band while Magellanics have two. Also adult Humboldts have a very dark brown-black head, face and back and white fronts. Their face has a white stripe running around the face, round behind the top of the eyes, down past the ear coverts and chin, joining on the throat. They are monomorphic with the male and female very similar in appearance and being difficult to tell apart. Often it is behavioural traits that reveal the gender of the two.

The Humboldt has stiff overlapping feathers that provide waterproofing and insulation to their bodies. Their eyesight is excellent on land and underwater. They are medium-sized penguins being larger than Little Blue penguins but smaller than King and Emperor penguins. They can be up to 28 inches high and weigh up to 11 pounds.

Hunting and Diet

 

Humboldt penguins are excellent swimmers and can reach speeds of up to 20 miles per hour. They use their wingers like flippers and steer with their tails and feet. They use their speed and manouverability make them formidable hunters.

Their diet consists of fish such as anchovies, herrings and crustaceans. Humboldts have a gland which gives them the ability to drink both fresh water and seawater.

Social Birds

 

Humboldt penguins are social birds forming large breeding colonies. They site their nesting burrows  very close together which aids communication. They build their nests in burrows, caves, or niches in rocks and boulders and sometimes on rocky shores.

Parents are able to recognise each other and their chicks using a combination of voice and sight. Each penguin has a unique voice which helps breeding pairs recognise each other and also their chicks.
These close-knit colonies help to provide a collective defence against skuas and gulls and other threats. As well as providing a secure nesting place the burrows also give the penguins shelter from the weather. 

Breeding

 

Humboldts begin to breed between the ages of two and seven years old. Depending on the availability of food Humboldts can breed at any time of the year. Females lay up to three eggs and both parents will take turns to incubate for about forty days. The chicks have greyish brown down when they are hatched.

Both parents take turns in caring for the chick and hunting for food. Eventually after about two months the parents will leave the chicks alone during the day while they go hunting. In times when food becomes scarce parents will feed the larger, stronger chick at the expense of the smaller ones.
After about seventy to ninety days the chicks will fledge, losing their down which will be replaced by grey feathers. These will gradually change to their adult plumage over time.

Predators and Threats


Humboldts are known to live up to around twenty years in the wild and up to 30 years in a zoo. Their total population is estimated to be about 6,000 pairs.

On land they are preyed on by foxes, wild dogs, and falcons such as caracaras. Gulls and skuas will kill chicks and steal eggs. In the sea they are preyed upon by toothed whales, fur seals and sharks.
Like other penguins they are vulnerable to changes in their ocean environment that may occur naturally such as the El Nino current which can have a devastating effect on their food chain.

Between 1982 -83, El Nino caused 65% decline in the Humboldt population. Although the population began to rise again it was badly depleted again in 1997-98 by another El Nino event.
They are also victims of human activity and their nests and eggs can be broken by humans gathering guano (droppings), which is used for fertiliser. This also causes damage to their breeding grounds.

Overfishing of their prey species is also a problem and they can also get caught up in fishing nets.
The International Union for Conservation of Nature lists them as Vulnerable A2bcde+3bcde+4bcde;C1+2b  on the IUCN Red List of Threatened Species.


References, Attributions and Further Reading

 

This is a version of an original article that was first published on Helium.com  on October 1st, 2009 and updated October 1st 2009 by zteve t evans. When  Helium.com became Critters 360 in November 2013 it was moved to there where a version remains at present.

 


Humboldt Penguin, From Wikipedia  

MarineBio Conservation Society - Humboldt Penguins, Spheniscus humboldti