- Larus delawarensis
Identification
L. 49 cm (17.5")
A fairly small white-headed gull, slightly larger than Mew Gull with lighter gray back, thick bill, very narrow white crescents on back, a few white primary tips show when standing, and pale yellow eye. Juveniles have contrasting white belly, pale rump with black tail band, and black primaries.
Similar Species
Mew Gull is slightly smaller with slightly darker back, dark eye, much thinner bill (sometimes with very thin ring), broad white crescents on back, and more white primary tips. Juveniles have uniform black-brown upperparts. Juvenile to 1st summer have brownish primaries.
California Gull is larger with slightly darker back, dark eye, red and black marks on slightly longer bill. 2nd winter similar to 1st winter Ring-billed but back darker gray, dark eye, and blueish legs.
Herring Gull is much larger Adult similar but with larger bill, pink legs, more extensive streaking on neck. 3rd winter similar to 1st winter Ring-billed but much larger with pink legs, and much more streaking to neck and head.
Distribution
In breeding season found in Canada and the northern United States. Winters south to Mexico. Rare but regular vagrant to the UK with records annually. Accidental to France, Germany, The Netherlands, Portugal, Spain, Hungary, Italy, Sweden, Norway, Denmark, Morocco, South Africa, and Japan.
Taxonomy
This is a monotypic species.
Habitat
Lakes, rivers and the coast.
Behaviour
Breeding
They build their nests on the ground. They tend to return to breed at the colony where they hatched. Once they have bred, they are likely to return to the same breeding spot each year, often nesting within a few meters of the last year's nest site.
Diet
Includes insects, fish, grain, eggs, earthworms and rodents.
