The black-and-white head pattern, a black stripe
running down the flanks and naked skin exposed on the head are
distinctive features of this genus. The hooked beak is deep and
strong. Spheniscus penguins must have evolved from a common ancestor
fairly recently as indicated by the close morphological similarity
amongst these species. All Spheniscus penguins are allopatric
(ie having separate distributions), however, so that most birds
can be safely identified by their location.
Young and immature birds lack the distinct black and white
plumage of the adults. Chicks, especially, closely resemble
Little Penguins.
Definitive means of identification of immature birds have yet
to be determined.
The most tropical of the penguin genera, found in the Galapagos
Islands, South America and Africa, they constitute the northern
end of penguin distribution. While Spheniscus penguins breed
in much warmer climates than other penguins, their breeding
areas are associated with cold, nutrient-rich currents.
Timing of the breeding season is far more flexible in Spheniscus than
in other penguins, with some populations breeding throughout
the year. The moult is much more variable within
Spheniscus than
within other penguin genera. Magellanic and African Penguins
moult after the breeding season, whereas Humboldt
and
Galapagos
Penguins moult one to four weeks before breeding.
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