- Explain how the biology of gulls relates to the types of damage associated with them.
- Explain the options for controlling gulls.
- Determine which types of control are appropriate for specific behaviors.
The term “gull”refers to 23 species of birds in North America that belong to the family Laridae, subfamily Larinae.
Gulls are classified as migratory species and are protected by federal and, in most cases, state laws. In the US, gulls may be taken only with a permit issued by the USDI-Fish and Wildlife Service (USFWS). Permits are issued only after frightening techniques, physical barriers, or both have been used correctly and qualified personnel certify that these methods have been ineffective. Some states may require an additional permit to kill gulls. No federal permit is needed to frighten or mechanically exclude gulls outside of the nesting season.
Gulls are robust birds with webbed feet, long wings and a slightly hooked beak. They are exceptional fliers, are often seen swimming and occasionally dive. Adult gulls are white with varying patterns of gray and black over the back, wings and head. Juveniles of larger species often are gray and take several years to develop adult plumage. The sexes are similar in appearance. The similarity of plumages can make identification of species difficult. Gulls range in size from the 6-ounce Sabine gull (Xema sabini) to the 4-pound great black-backed gull (L. marinus).
Herring (L. argentatus, Figure 1) and ring-billed gulls (L. delawarensis) are the most common gulls. Both are found throughout North America including coastal and inland areas, unsettled areas, in large cities, and farm fields (Figure 2).
Other common species include the laughing gull (L. atricilla), Franklin’s gull (L. pipixcan), great black-backed gull, and California gull (L. californicus). Some species are limited to coastal habitats, while others may occur inland seasonally, rarely, or in specialized habitats.
Voices and Sounds
Calls vary from the deep growl or “gaap” to the short “yek” or “ye ye ye” series.
Tracks and Signs
Gulls have webbed feet with distinct toe marks in the tracks (Figure 3).