Franklin's Gull Leucophaeus pipixcan Scientific name definitions

Editor's Note: Due to a recent taxonomic revision, this species account is still being edited and may contain content from an earlier version of the account.

Editor's Note: Studies of mitochondrial DNA in the subfamily Larinae have suggested that the heretofore broadly defined genus Larus is paraphyletic. Reclassification of this genus now places Franklin's Gull in the genus Leucophaeus. See the 49th Supplement to the AOU Check-list of North American Birds for details. Future revisions of this account will account for this change.

The Franklin's Gull is a small, black-hooded gull that nests in small to very large colonies in marshes of interior North America. Its light, buoyant flight and pinkish bloom led early ornithologists to call it the Rosy or Prairie Dove, although over much of its prairie range it is called simply seagull. A colony of 10,000 or more pairs nesting over water in a bulrush or cattail marsh is a vibrant place, bustling with activity. Bent (Bent 1921 Bent, A. C. (1921). Life histories of North American gulls and terns. United States National Museum Bulletin 113. Close ) wrote that “a breeding colony of Franklin's gulls is one of the most spectacular sights,” and Job (Job 1910 Job, H. K. (1910). Franklin's Gull. Bird-Lore 12:124-127. Close ) commented that it is “one of the prettiest sights which the wide prairies can afford.”

The Franklin's Gull depends on extensive prairie marshes for breeding, and entire colonies may shift sites from year to year depending on water levels. Once threatened by habitat loss due to large-scale drainage projects and the Dust Bowl years, this species has regained numbers with the creation of large wetlands, mainly on protected national wildlife refuges. Colony shifts continue to occur, however, influenced by drought and fluctuating water levels.

In migration and the breeding season, this is a familiar bird with large flocks following the plow or disk harrow, eating earthworms, grasshoppers, grubs, seeds, and occasionally mice. On lakes and marshes, it also feeds aerially on flying insects and snatches recently emerged insects from the water or plant surfaces. After an extensive period of post-breeding wandering in the prairie regions, it migrates through Mexico to the west coast of South America.

This species was first collected by Dr. John Richardson, on the first Sir John Franklin expedition to northwestern Canada in 1823, probably from the Saskatchewan River. Sabine described the bird, noted its unique characteristics, but mistakenly called it a Laughing Gull (L. atricilla). After the second Franklin expedition, Richardson named it Franklin's Rosy Gull (L. franklinii), a name widely used for 90 years. Although written in 1830, Richardson's publication was not released until 1832 (Swainson and Richardson 1832 Swainson, W. and J. Richardson. (1832). Fauna boreali-Americana. Part 2: The birds. London, UK: J. Murray Publ. Close ), so that Wagler's description of L. pipixcan from Mexico published in 1831 has priority (Houston and Street 1959 Houston, C. S., and M. G. Street (1959). The birds of the Saskatchewan River. Special Publication 2. Saskatchewan Natural History Society, Regina, SK, Canada. Close ). Audubon apparently never encountered this species and did not illustrate it (Job 1910 Job, H. K. (1910). Franklin's Gull. Bird-Lore 12:124-127. Close ).

Franklin's Gull is susceptible to human disturbance early in its breeding cycle and will desert colonies readily. Because of their ephemeral nature and the vulnerability of prairie marshes to drought and drainage, breeding colonies often shift from year to year, and in some years local populations may not breed at all. There is controversy concerning current population levels of this species and apparent declines in its numbers over the past 30 years (Knopf 1994 Knopf, F. L. (1994). "Avian assemblages on altered grasslands." In A century of avifaunal change in western North America., edited by J. R. Jehl and N. K. Johnson, 247-257. Stud. Avian Biol. no. 15. Close ), although Southern (Southern 1980 Southern, W. E. (1980). "Comparative distribution and orientation of North American gulls." In Behavior of marine animals, edited by J. Burger, B. L. Olla and H. E. Winn, 449-498. New York: Plenum. Close ) noted that this gull is experiencing sufficient reproductive success to sustain populations. Because it nests in remote marshes and rarely wanders far from breeding colonies when eggs and young are in the nest, Franklin's Gull is usually missed by standard breeding bird surveys, contributing to speculation about loss of numbers. Colony surveys appear to reflect numbers more accurately.