Calonectris diomedea
Difficult human access and rocky cliffs makes this area an ideal location for a significant population of Cory's shearwater ("Calonectris borealis") and common tern ("Sterna hirundo"), which annually migrate through the Azores to nest, in addition to grey heron ("Ardea cinerea"), sanderling ("Calidris alba"), Kentish plover ("Charadrius alexandrinus"), and other marine birds such as seagulls (family "Laridae"). The presence of these birds, protected by Annex I of the Habitats Directive, resulted in the islets' reclassification as a "Special Protection Zone", warranting its inclusion within the listing of "Important Bird Areas" () in the Azores (published by BirdLife International).