The Franklin’s gull is a small gull with short wings and a short bill, and a dark hood at all times of year. During breeding season, its entire head is black except for white crescents above and below its eyes. At other times of year, the hood is restricted to the back of the head and cheeks. It has white underparts and a gray back. Its wings are mostly white underneath—which is distinctive—and gray on top with a white band across the trailing edge and black wingtips. Its bill and legs are red in breeding season, otherwise dark.
The Franklin’s gull’s call is a loud, nasal laugh with short breaks between each syllable: cah-cah-cah-cah-cah.
The Franklin’s gull breeds in southern Canada, from Alberta to southern Manitoba and south into the northern Great Plains, from Montana to Minnesota. In these areas it can be found in prairies, marshes, and wetlands. It passes through the central United States during migration to winter along South America’s west coast. There, it prefers sheltered bays and estuaries and sometimes moves further inland to live near lakes.
Franklin’s gull is an omnivore, depending on what’s readily available and opportune. Its diet includes grasshoppers, flies, worms, fish, seeds, snails, crayfish, and garbage. It typically forages in flocks, walking around the ground and picking up food as it goes.
The Franklin’s gull builds its nest over water in large colonies. Both sexes construct a large, bulky platform of reeds and plant down that is anchored to standing vegetation. The female lays one to four eggs that are yellowish or greenish brown and spotted with dark brown. Both sexes incubate the eggs for 23-26 days before hatching. Both parents feed the young while they remain in the nest for a minimum of 20 days. The hatchlings are able to leave the nest and fly after 35 days, after which the parents may continue to watch and care for them for an additional week.