Gull (Western)

A large, dark-backed gull of the Pacific Coast, the Western Gull is seldom found far from the ocean. Like most gulls, the Western Gull is an opportunistic feeder, capturing its own live prey, scavenging refuse, or stealing food from seals and other gulls. It is known to steal milk from lactating female seals while they lie on their backs sleeping on the beach.

In colonies with many more females than males present, two females may establish a pair bond. Each lays eggs, and then takes care of the double-sized brood. The female-biased sex ratio of some Western Gull colonies may have been the result of pollution by pesticides that acted like estrogens and made some male embryos develop as females. (Dana Point, CA)