A situation that might make usurpation favorable includes periods of low food availability that are characteristic of El Niño events. While this strategy is used to gain mates, there is risk of injury and even death of the invader. ( Schwarts, et al., 199)Īnother rare aspect of the mating of Humboldt penguins is that males may start usurps, defined as an unpaired male that invades the nest of an established pair. Extra-pair mating is always initiated by the female but the costs and benefits of this strategy are not well understood. Although they are typically monogamous, in rare cases the female will solicit another male for mating. Humboldt penguins are monogamous and recognize their partner in the colony through distinct vocal cues. The solid breast band also helps in distinguishing adults from juveniles who have a darker head. Distinctive of the species is a solid, black breast band that helps to differentiate them from Magellanic penguins ( Spheniscus magellanicus). Humboldt penguins have black heads with white stripes under the eyes that wrap around the side of their head and connect at the chin forming a horseshoe shape. They have blackish-gray feathers on the back and white feathers on the chest. Humboldt penguins are medium-sized, ranging from 66 to 70 cm in length and weighing from 4 to 5 kg. Penguins will choose such sites for nesting but will occasionally use a cave along the shore. The Pacific coast of South America is characteristically rocky and is also known for having large deposits of guano. ( Taylor, et al., 2004)Īs is the case for many penguins, Humboldt penguins must come ashore to rest, breed, and raise young. Breeding penguins spend less time offshore with trips averaging 22.4 hours with a maximum of 35.3 hours. Non-breeding penguins spend an average of 60.0 hours in the water before returning to land with the maximum trip lasting 163.3 hours. The amount of time the spend in water is associated with breeding status. Humboldt penguins spend a majority of their time in coastal waters. This area is located adjacent to the Humboldt Current, a large oceanic upwelling characterized by cold, nutrient rich waters. Their range extends from Isla Foca in the north to Punihuil Islands to the south. These penguins possess a supraorbital gland, which extracts excess salt from their blood and excretes it through their beak, allowing them to drink salt water along with fresh water.Humboldt penguins are endemic to the subtropical Pacific coasts of Chile and Peru.The overlapping pattern of their feathers helps them to keep waterproof and warm.Their dense plumage protects them from winds up to 60 miles per hour.With a body designed for swimming, they quickly catch prey underwater.Their excellent eyesight helps them see properly both on land and underwater.The lifespan of these penguins ranges between 15 and 20 years. They undergo about two weeks molting period that usually happens before mating.Every penguin has a different voice that helps them to recognize their mate and offspring.While feeling threatened, they produce a honk-like yelling sound and a braying call to attract a mate. They use different calls to communicate.Due to warm temperatures throughout the year, they do not need to migrate.These birds travel a long distance from their nests to forage. They gather in large colonies, which provide them protection from predators.
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