Adult has dagger-like yellow bill and black crest feathers. Head, neck and underparts otherwise whitish except for black streaks on front of neck and breast. Back and wings are blue-grey. In flight, wings are broad and rounded with black flight feathers; filght pattern comprises slow, flapping wingbeats.
Widepsread and common on wetlands and sheltered coasts.
Spotted in the Rio Formosa Natural Park, with 2 others, fishing with no success. :)