Puffinus creatopus Coues, 1864

Sexual Size Dimorphism

Identification: On average, male pink-footed shearwaters are larger than females. Morphological traits including bill size, tail length, head length, and average body size are linked not only to sex but also to breeding locality.

Morphological Adaptation Drivers

These differences may be adaptations to local environmental conditions such as food availability, prey type and mobility, and wind speed. Among procellariiformes, larger wing area is generally associated with feeding on highly mobile prey, lower wind speeds, and less abundant, more dispersed food sources.

Size Variation Explanation

This means that size differences between pink-footed shearwaters from different breeding locations may reflect both sex differences and colony-specific differences in foraging habits.

Vocal Behavior

For vocal behavior, pink-footed shearwaters are not especially vocal, but they can produce a horse-like whinny when feeding.

Breeding Distribution

Distribution and habitat: Pink-footed shearwaters breed on islands off the coast of Chile, specifically the Juan Fernandez Archipelago and Isla Mocha.

Non-breeding Range

During the non-breeding season, they migrate north through the eastern Pacific Ocean, spending this period between Northern and Southern Peru, or off the coast of North America from Southern California to Vancouver.

Migration Distance

They complete trans-equatorial migrations of 11,000 km, and some individuals travel a total distance of up to 31,000 km from their Chilean breeding sites.

Habitat Use

They use coastal and pelagic waters as stopover sites during migration, and utilize continental shelf and slope habitats during the non-breeding season.

Foraging Location Preference

Feeding ecology: Pink-footed shearwaters strongly prefer to feed close to the mainland coast, which likely reflects both local oceanographic conditions and food availability. This preference may be connected to their favoring of high salinity waters with surface temperatures between 14 and 18 degrees Celsius.

Primary Prey Associations

Their foraging sites align with areas that have high populations of their primary prey: anchovies and sardines.

Foraging Trip Duration

Pink-footed shearwaters are known to make long feeding trips that last one to two weeks.

Dual Foraging Strategy

Pelagic seabirds that breed in the southern hemisphere typically follow a dual foraging strategy, alternating between short and long foraging trips. This strategy is thought to be a compromise between meeting the need for regular feedings for chicks and allowing adult birds to maintain their body condition by foraging in highly productive waters.

Foraging Research Gaps

Still, few studies have been done on the movement ecology of pink-footed shearwaters that document their foraging behavior.