Sunday, July 7, 2013

Ring-billed Gull


Familiar acrobats of the air, Ring-billed Gulls nimbly pluck tossed tidbits from on high. Comfortable around humans, they frequent parking lots, garbage dumps, beaches, and fields, sometimes by the hundreds. These are the gulls you're most likely to see far away from coastal areas—in fact, most Ring-billed Gulls nest in the interior of the continent, near freshwater. A black band encircling the yellow bill helps distinguish adults from other gulls—but look closely, as some other species have black or red spots on the bill.

This male gull was photographed on the shores of Charleston Bay. It doesn't have the yellow bill signifying it is a first summer or non-breeding adult male.

Many, if not most, Ring-billed Gulls 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. Many individuals return to the same wintering sites each winter too. Although it is considered a typical large white-headed gull, the Ring-billed Gull has been known to hybridize only with smaller, black-headed species, such as Franklin's, Black-headed, and Laughing gulls. Migrating Ring-billed Gulls apparently use a built-in compass to navigate. When tested at only two days of age, chicks showed a preference for magnetic bearings that would take them in the appropriate direction for their fall migration. The gulls also rely on landmarks and high-altitude winds to provide directional cues.

Ring-billed Gull Range Map

No comments:

Post a Comment