The Glaucous-winged Gull is a large white-headed gull. Its yellow bill has a red spot, its back and wings are silver-gray, and its legs are pink. It is a resident of coastal regions of the north Pacific Ocean, from northern Oregon to northern Japan. In winter it retreats from its northernmost range and can be found as far south as Baja California. You can see it along the waterfront or flying overhead, just about anywhere in Edmonds, throughout the year. In winter its bright white head becomes darkly streaked. As you can see from LeRoy’s photos, the Glaucous-winged Gull even nests here in Edmonds.
In our southern end of its range, the Glaucous-winged Gull readily breeds with the Western Gull, creating hybrids that are referred to locally as Olympic Gulls. The wing tips of Glaucous-winged Gulls have medium gray markings. The Western Gull has black wing tips and somewhat darker gray wings and back. In the hybrids you may notice a range of color in the wing tips from a darker gray to a lighter black. Many of the Olympic Gull hybrids can be seen along the inland marine waters. In Washington there are often more hybrids than Glaucous-winged Gulls.
The Glaucous-winged Gull has an omnivorous diet. It will eat a variety of fish and crustaceans, smaller birds, eggs, and small mammals, as well as some plant material. It also scavenges around open garbage and will feed on carrion. It forages for food while walking or swimming, and even plunge dives from flight. While in flight, it will take hard-shelled crabs or clams and drop them on rocks repeatedly until they break open.
Breeding does not take place until the Glaucous-winged Gull reaches four years of age or older. It typically breeds in densely-packed colonies but has adapted to smaller groups on flat roofs of buildings or even single nests in protected sites, such as in the marina where LeRoy watched the hatchlings in his photos. Both sexes build the nest, which is a shallow scrape lined with seaweed, moss, grass, and debris. There are usually 2 – 3 eggs that are incubated by both adults for 26 – 29 days. The downy young leave the nest two days after hatching.They can not fly until they are 5 – 7 weeks old. Until that time, both parents feed the young.
The Glaucous-winged Gull is described as a four-year gull because it does not develop its adult plumage until its fourth year. It always has pink legs. In its first and second winters it has an all-dark bill. It is uniformly pale brownish in its first winter and then develops some gray plumage on its back during its second winter. By the third winter, only the tip of the bill is black and the bird has most of the gray and white feathers seen on an adult in its fourth year.
— By Carol Riddell