The Laughing Gull (Leucophaeus atricilla) is a medium-sized gull of North and South America. Named for its laugh-like call, it is an opportunistic omnivore and scavenger. It breeds in large colonies mostly along the Atlantic coast of North America, the Caribbean, and northern South America. The two subspecies are: L. a. megalopterus – which can be seen from southeast Canada down to Central America, and L. a. atricilla which appears from the West Indies to the Venezuelan islands. The laughing gull was long placed in the genus Larus until its present placement in Leucophaeus, which follows the American Ornithologists’ Union.
The Ring-billed Gull (Larus delawarensis) is a medium-sized gull. The genus name is from Latin Larus which appears to have referred to a gull or other large seabird. The specific delawarensis refers to the Delaware River. The head, neck and underparts are white; the relatively short bill is yellow with a dark ring; the back and wings are silver gray; and the legs are yellow. The eyes are yellow with red rims. This gull takes three years to reach its breeding plumage; its appearance changes with each fall molt. The average lifespan of an individual that reaches adulthood is 10.9 years.