The male Boat-tailed Grackle is 37–43 cm (15–17 in) long and weighs 165–250 g (5.8–8.8 oz). Adult males have entirely iridescent black plumage, a long dark bill, a pale yellowish or brown iris and a long keel-shaped tail. The adult female is much smaller at 26–33 cm (10–13 in) long and a weight of 90–115 g (3.2–4.1 oz). She is also distinctive via her shorter tail and tawny-brown coloration, which covers the body apart from the darker wings and tail. The wingspan in adult birds is 39–50 cm (15–20 in).
The Boat-tailed Grackle (Quiscalus major) is a passerine bird of the family Icteridae found as a permanent resident on the coasts of the southeastern USA. It is found in coastal saltwater marshes, and, in Florida, also on inland waters. The nest is a well-concealed cup in trees or shrubs near water; three to five eggs are laid.