Glaucous Gull (us-RGV)
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Contents |
Regional Information
Range, Abundance, and Seasonal Variations
A vagrant to the Rio Grande Valley. Seen at S. Padre Island, Boca Chica Beach, or the Brownsville landfill.
Directions and Maps
General Information
Size
Length: ??cm (??in), Wingspan: ??cm (??in)
Field Marks
This is a large and powerful gull, very pale in all plumages, with no black in the wings or tail. Sexes similar. Bill large with distinct gonydeal angle, squarish head, wingtips extend slightly beyond tail at rest. Adult breeding: Bright yellow bill with red spot at gonys, pink legs, light eye, white head, neck, breast, and belly, gray back and upperwings, white tertial crescent, primary tips white, white tail. Adult non-breeding: Like adult breeding but blurry brown streaking and spotting on head and nape. Juvenile/First-year: They take four years to reach maturity. Pinkish bill with distinct black tip, ghostly white or pale with pale brown barring, white primaries and secondaries, white tail with gray to pale brown speckling. Second-year: Pale bill with black tip, pale head, neck, upper breast, wings, and belly, pale gray back. Third year: Like adult but often lacks adult bill pattern.
Similar species
Glaucous Gulls are quite similar to Iceland Gulls but are larger, have larger bills, flatter heads, and, at rest, shorter wingtips that barely project beyond the end of the tail. Adult Iceland Gulls have dark primary tips in the United States (Greenland and European birds can have white wingtips). First-winter Glaucous Gulls have pink-based, not black, bills. Other gulls lack the white primary tips of the Glaucous Gull.
Sounds
The call is a "laughing" cry like Herring Gull.
Feeding & Behavior
These are omnivores like most Larus gulls, and they will scavenge as well as seeking suitable small prey. These birds forage while swimming or walking, also may pick up items off water or catch small birds while flying. They often follow fishing boats.
Habitat & Nesting
This species breeds colonially or singly on coasts and cliffs, making a lined nest on the ground or cliff. Normally, 2-4 eggs are laid.
Range
Breeds in the arctic regions of the northern hemisphere and the Atlantic coasts of Europe. It is migratory, wintering from in the North Atlantic and North Pacific oceans as far south as the British Isles and northernmost states of the USA, also on the Great Lakes. A few birds sometimes reach the southern USA and northern Mexico.
Resources
