What type of Gull? Differences between American Herring Gull and Ring-Billed Gull
American Herring Gull
Physical Characteristics: 24-26 inches in length, 56-60 inch wingspan, 800-1250g weight. Bill is yellow with red spot on lower bill, legs/feet are pink/skin coloured, dark wingtips, pale iris with orangish orbital ring (breeding). Appear barrel-chested and broad-winged in flight. Long and gradual forehead slope.
Juvenile Characteristics: mottled brown juveniles, second-year birds are brown but show gray on the back. Third-years have more gray on the back and more white on the head and underparts.
Eggs: 1-3 eggs/clutch, 2.6-3.0 inch length, 1.9-2.1 inch width, light olive or greenish coloured with darker splotches or speckling, 31-32 day incubation period, 45-50 day nestling period.
Diet: prey on marine invertebrates, fish, insects, smaller seabirds, and even on adults, young, and eggs of other gulls. Along rocky shores, they take mussels, crabs, sea urchins, and crayfish. On mudflats, they seek worms, small clams, and mussels.
Specific to American Herring Gull:
- lake and pond habitat
- lower pitched vocalizations
- known to hybridize with other gull species
- 4 years to reach adult breeding plumage
- may feed on nests, young or adults of other gulls in colony and other seabirds
- pairs hollow out up to 4 depressions prior to nesting season before choosing one to lay eggs
- highest hatching success rate
Physical Characteristics: 17-18 inches in length, 48 inch wingspan, 300-700g weight. Bill is yellow with black ring and slimmer/shorter, legs/feet are yellow, prominent black wing tips with white spot near end, pale iris with thin red orbital ring (breeding). Short and steep forehead slope.
Juvenile Characteristics: During their first two years, Ring-billed Gulls are a mottled brown and gray with a pink bill and legs.
Eggs: 2-4 eggs, 2.0-2.6 inch length, 1.4-1.8 inch width, pale olive gray colour with dark brown speckles, 20-31 day incubation period, nestling period 4-5 days.
Diet: mostly fish, insects, earthworms, rodents, grain, and garbage.
Specific to Ring-Billed Gull:
- shoreline habitat
- more abundant on the great lakes
- more commonly seen inland than other gull species
- feeds more on food taken from land
- higher pitched vocalizations
- will nest on sand, soil, concrete, slag, boulders, driftwood, or rubble
Similarities between species:
- Male larger than females and may appear more fierce
- Ground foragers/nesters
- Extremely opportunistic
- In Sarnia year round