Birds
Rock Shag
Phalacrocorax magellanicus · also called Magellanic cormorant
Diving through rough surf along exposed rocky headlands, a rock shag makes its living on some of the roughest coastline in southern South America, a different lineage entirely from the more famous blue-eyed shags found on the far side of the Southern Ocean.
Overview
The rock shag, Phalacrocorax magellanicus, is a Least Concern seabird native to ocean and coastal habitat across southern South America and the Falkland Islands. Its distinct genus separate from the New Zealand blue-eyed shags, its glossy dark-and-white plumage, and its ability to forage in rough coastal surf make it one of the more resilient and widespread cormorant relatives found anywhere in the Southern Hemisphere.
A different lineage, a similar lifestyle
Despite looking and behaving much like the blue-eyed shags found thousands of kilometres away in the New Zealand subantarctic, the rock shag belongs to an entirely separate genus, a case of similar diving lifestyles evolving independently on opposite sides of the Southern Ocean.
Status
Least Concern, remaining widespread and generally stable across suitable rocky coastal habitat in southern South America and the Falkland Islands.
Rock Shag: common questions
Is the rock shag related to the blue-eyed shags of New Zealand?
No, this species belongs to a different genus entirely from the blue-eyed shags found across the New Zealand subantarctic islands, despite both groups sharing a similar diving lifestyle.
What does the rock shag look like?
This species has mostly dark, glossy plumage with some white patches, a pattern distinct from the stronger black-and-white contrast seen in several related cormorant species.
Where does the rock shag breed?
This species breeds in colonies on rocky cliffs and headlands along the coasts of southern Chile and Argentina, as well as the Falkland Islands.
How well does the rock shag cope with rough water?
This species is a strong, agile diver capable of foraging effectively even in the rough surf typical of its exposed rocky coastal habitat, unlike some more sheltered-water seabirds.