- Gulls, Terns, and Skimmers
Once considered a subspecies of the more common and widespread Western Gull, the Yellow-footed Gull breeds only in Mexico's Gulf of California. However, post-breeding wanderers regularly travel north to California's Salton Sea where they are sought after by avid birders.
A large, white-headed gull with a dark slate-colored back, its thick bill is bright yellow, matching the color of its legs. Easily identified within its range, as no other gull approaches it in size and darkness other than the closely-related, but pink-legged, Western Gull.
Distribution and Population Trends
Endemic to the Gulf of California, Yellow-footed Gull regularly wanders north to southern California's Salton Sea (an Audubon IBA) during the nonbreeding season. Since this species? discovery in the 1960's, Yellow-footed Gulls have increased as post-breeding wanderers to the Salton Sea where they are now annually recorded in the hundreds with maxima upwards of 1,000 individuals. Little is known of their overall population trend in the Gulf of California.
Yellow-footed Gull nests on islands in the Gulf of California or on rocky islets of the mainland. It can nest both independently and as part of a colony. This bird forages in tidal, intertidal, and pelagic areas away from the nesting site, feeding on marine fishes and invertebrates. It is also a scavenger and will prey upon seabird chicks and eggs from around its nest site. Most individuals are not migratory, but an increasing number are moving north to the Salton Sea upon completion of breeding in the Gulf.
Recent trends suggest this species is stable, if not increasing both on its breeding grounds as well as at the Salton Sea. The species is at risk by virtue of its limited geographic range. While the Migratory Bird Treaty which was signed by Mexico in 1936 does extend protection to this species, enforcement is limited. Some breeding colonies are protected but others are not and tourists are allowed to visit freely. Owing to their limited range, non-native predators, pollution and overfishing are possible threats that could potentially have a sudden and drastic effect on the species.
Currently, a few scattered preserves in the Gulf of California represent the only credible source of protection for this species. A Biosphere Reserve was designated under UNESCO's Man and the Biosphere Programme in 1995 that covers 124 islands in the Gulf of California. Named Islas del Golfo de California (Gulf of California Islands), numerous activities have been undertaken to make the islands suitable for seabirds. Unfortunately, no other measures are being taken to secure breeding sites. Public education to tourists visiting offshore islands in the Gulf of California should be integrated into management plans. A simple solution might be to erect bilingual signs and fencing to prevent people from walking through breeding colonies.
What Can You Do?
Audubon's Important Bird Areas program is a vital tool for the conservation of Yellow-footed Gulls as well as other species. To learn more about the Important Bird Area programs in California and other states, and how you can help, visit: http://www.audubon.org/bird/iba/.
U.S. National Wildlife Refuges like the Salton Sea NWR in southern Californua provide essential habitat for Yellow-footed Gulls, and a great number of other species throughout the U.S. and its territories. Unfortunately, the refuge system is often under-funded during the U.S. government's budgeting process. To learn more about how you can help gain much needed funding for U.S. National Wildlife Refuges, visit: http://www.audubon.org/campaign/refuge_report/
CIPAMEX, Audubon's BirdLife International partner in Mexico, has an Important Bird Areas program that is working to protect nesting areas for Yellow-footed Gull and many other species. To learn more about Mexico's Important Bird Areas program and how you can help visit: http://184.108.40.206/wwwcampus/cipamex/
Information on where Yellow-footed Gulls occur and in what numbers is vital to conserving the species. Help in monitoring this and other species by reporting your sightings to eBird. A project of Audubon and the Cornell Lab of Ornithology, eBird is the world's first comprehensive online bird monitoring program: http://www.audubon.org/bird/ebird/index.html.
Audubon's Living Oceans Campaign is working to reduce mortality of seabirds caused by various fisheries and to maintain healthy marine ecosystems by regulating certain fisheries. You can help by writing letters, educating others about the issues, and supporting the program. To find out more check out the Living Oceans website at: http://www.audubon.org/campaign/lo/index.html.
Patten, Michael A. 1996. Yellow-footed Gull (Larus livens). In The Birds of North America, No. 243 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D. C.