|
Gulls | Gull Overview | Gull Damage Assessment | Gull Damage Management | Gull Resources | Gull Acknowledgments | ICWDM | Wildlife Species Information |
Fig. 1. Various species of gulls are becoming an increasing problem at specific locations throughout North America.
Contents |
Identification
The term gull refers to members of a group of 23 North American bird species that belong to the family Laridae, subfamily Larinae. Gulls are robust birds with webbed feet, long wings and a slightly hooked beak (Fig. 1). They all possess exceptional flying ability. They are often seen swimming, and occasionally dive underwater. Adult gulls are white, with varying patterns of gray and black over the back, wings, and head. The young of larger species are often gray and take several years to develop adult plumage. The sexes are similar in appearance.
Distribution
The herring (Larus argentatus) and ring-billed (L. delawarensis) gulls are the most common and widespread of the species. They are distributed throughout North America, from coastal to inland areas, from unsettled areas to the downtown cores of large cities, from farmers’ fields to fastfood outlets and drive-in theaters. Other common species include the laughing gull (L. atricilla), Franklin’s gull (L. pipixcan), great black-backed gull (L. marinus), and California gull (L. californicus). Some species are limited to coastal habitats, while others may occur inland seasonally, rarely, or in specialized habitats.
|
Gulls | Gull Overview | Gull Damage Assessment | Gull Damage Management | Gull Resources | Gull Acknowledgments | ICWDM | Wildlife Species Information |
General Biology, Reproduction, and Behavior
Most gulls nest in colonies on sand-and gravel-covered shorelines and islands. They build nests on the ground and produce 3 to 5 eggs per nest. In the Great Lakes region, the number of ring-billed gulls has been increasing at about 10% per year since the early 1970s. Bent (1947) said of it, “the ring-billed gull yields readily to persecution, is easily driven from its breeding grounds and seems to prefer to breed in remote, unsettled regions far from the haunts of man.” However, a colony on Leslie Spit on the waterfront of Toronto, Ontario, increased from 20 pairs in 1973 to 75,000 to 80,000 pairs in 1982 (Blokpoel 1983). It appears that ring-billed gulls have changed some of their habits in recent years and have adapted to humans in their environment. A colony of laughing gulls in the Jamaica Bay Unit of Gateway National Recreation Area, New York, increased from 15 pairs in 1979 to 7,600 pairs in 1990 (Richard A. Dolbeer, pers. commun.).
Food Habits
Gulls feed on land or water on aquatic animals, terrestrial invertebrates and small vertebrates, plant remains, carrion, and refuse. They frequently take the eggs and young of other nesting seabirds. Small species, including ring-billed, laughing, and Franklin’s gulls, may also feed in the air on flying insects.
Victor E. F. Solman. Wildlife Biologist (retired). Canadian Wildlife Service Ottawa, Ontario Canada K2A 2P1
Comments
Subscribe to this page's comments
Post a comment about this topic