Overall, little is known about this South American species and what is known largely comes from descriptive studies scattered through time and concentrated at a few select breeding colonies.

[5] Chilean skuas tend to be dark on their back, flanks, and cheeks, and uniformly light underneath.

[5][6] The Chilean skua is endemic to South America, occupying coastal habitats from central Peru to northern Argentina.

It nests between southern Chile and Cape Horn, Argentina, but its wintering range extends into Brazil, where it exploits the tropical coastal waters.

[6] Breeding adults show a preference for sandy coastline with beached kelp and freshwater streams.

At the breeding colony, it performs a long-call which consists of ten to twelve short nasal barks.

[7] This call is seemingly unrelated to chick-rearing and has been described as almost goose-like due to its distinctly deep and hoarse nature.

[12][14] From November to February or March,[7] Chilean skuas aggregate into breeding colonies in sandy coastal habitat.

[7] In the absence of their parents, chicks will remain motionless at their nest site and camouflage themselves in the sand among patches of giant kelp.

In the presence of their parents, they will venture a bit further from the nest but will walk back with their wings folded against their body and their head under their shoulders at the first sign of a threat.