Unlike their far flying relatives the Arctic Terns, Inca Terns are non-migratory. They spend their lives living in their cliff areas, where they also breed and raise young. They are monogamous birds and lay clutches twice a year, usually around April/May and October. Nests are formed in natural burrows, and both parents assist in rearing the chicks, who remain in the nest for 7 weeks.
Because they are seabirds, Inca Terns feed on fish. They actually share a predatory range with Humboldt Penguins, but there is little competition over food as the penguins are able to retrieve their meals from much deeper ocean depths. Inca Terns obtain their food by flying over the water, spotting fish, and then diving beak fish into the waves.
Inca Terns are a near threatened species, with their wild populations on the decline. The birds survival is quite understandably tied to their food supply, which has been negatively affected by El Nino events in the past. It is estimated that the total population numbers around 150,000.