b i r d w a t c h
Ring-Billed Gull
The adaptable coastal bird unaffected by human activity
By Susan Campbell
Come late
November and then through December, ring-billed gull numbers predictably swell, peaking sometime in January. Flocks can easily number in the hundreds, and are remarkably unaffected by human activity. Of course, our actions over the past century are what facilitated the species’ winter range expansion in the first place.
Familiar to most residents of the coast, birdwatchers or not, the ringbilled gull is characterized by its white head and chest, gray back, and the black vertical band — or ring — around its bill. When perched, this mediumsized gull displays black wingtips with white spots that extend beyond its squared-off tail. The legs, like the tail, are bright yellow. Wintering adults exhibit gray-brown flecking on the head. Immature birds will have varying amounts of brownish streaking as well as pinkish legs and bill. It takes three years for an individual to acquire adult plumage. Ring-billed gulls nest up north, on small islands across the Northern Tier and throughout much of Canada. They seek sparsely vegetated habitat and are often found sharing islands with other species of gull and tern. Ring-billeds are known to return to their natal area to breed, often nesting mere feet away from where they nested the year before. They are likely to return to familiar wintering grounds as well, and have a highly tuned sense of direction, using a built-in compass as well as landmarks (such as rivers
The Art & Soul of Wilmington
and mountain ranges) to successfully navigate in spring and fall. Population numbers for the species were significantly impacted by millinery trade, egg collectors and human encroachment by early settlers in the early 1900s. But with the passage of the Migratory Bird Treaty Act in 1918, ring-billed gull numbers began to stabilize. No longer was it legal to shoot adults for their feathers or collect their eggs for food. Additionally, introduction of fish species such as the alewife and inundation of new habitat in the western Great Lakes region increased breeding productivity in the decades that followed. An increase in landfills, farmlands and reservoirs has created more foraging habitat for these birds. Although ring-billeds prefer insects, worms, fish, small rodents, and grains and berries, they are highly adaptable. As a result of food abundance, reproductive success has been even higher in the last thirty years — especially around the Great Lakes and the eastern United States. That said, this species has become something of a nuisance in some areas. Control measures (scarecrows, noise makers, materials that move in the wind) have been employed but with very little success. Large flocks of ring-billed gulls are likely to get the attention of birdwatchers come late winter. At that time of the year, with several thousand along the coast, the odds of finding a vagrant mixed in increase. It is possible to tease out a California gull or perhaps a black-headed gull from the hundreds sitting on the beach or a recently plowed field, if one has good optical equipment — and a lot of patience. b Susan would love to receive your wildlife sightings and photos. Contact her by email at susan@ncaves.com, or by calling (910) 949-3207. December 2013 •
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