yellow-shouldered blackbird Agelaius xanthomus

An inhabitant of coastal mangroves and nearby scrublands. This species is all black, except for a bright yellow shoulder patch—a combination that eliminates all other species in its range. At times, the shoulder patch is hidden such that it can resemble the Shiny Cowbird. The Shiny Cowbird has glossier plumage and a shorter, thicker bill. Vocalizations include a rough “chet” or “chulp” and a braying “naaaaaaaah.”