are among the most often seen birds in British Columbia, especially
along the coast. There are many species that occur in the province,
but the Glaucous-winged is probably the most familiar species.
It's name means
"pale-winged", a reference to the colour of its wingtips,
which are the same colour as its mantle, or back. It is a resident
along the coast, nesting primarily in colonies on rocky islets offshore.
With the availability of offal from fish processing, and garbage
at landfills, these gulls have increased in numbers. In response
to pressure on the breeding colonies, some birds are now nesting
on building roofs. The Capital Regional District has implemented
a system of overhead lines at its landfill site, which effectively
deters most gulls from accessing the garbage.
Gulls nest in the summer, with most pairs producing two or three
mottled chicks. These fledge when they are about six weeks old.
The Glaucous-wing is a "four-year" gull, taking this long
to change from mottle brown juvenile plumage, to the grey-backed
, white-headed plumage of an adult. One bird, recognizable because
it only had one leg, is known to have lived for over thirty years,
but fifteen is probably a more normal maximum.
Gulls are opportunistic
feeders. When tides are low, they feed on marine life; it is not
uncommon to see gulls with half-swallowed sea stars. They also will
follow farm machinery, to feed on small mammals and invertebrates.
frequently hybridizes with the much darker Western Gull (L. occidentalis).
There are many individuals that are intermediate in colour, especially
in the Puget Sound area, and this gives birders some challenging