Introduction

Breeding adult Franklin's Gull, Benton Lake, MT, July

Figure 1. Regular summer (breeding) distribution of the Franklin’s Gull.

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 (1921) wrote that “a breeding colony of Franklin’s gulls is one of the most spectacular sights,” and Job (1910) 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), so that Wagler’s description of L. pipixcan from Mexico published in 1831 has priority (Houston and Street 1959). Audubon apparently never encountered this species and did not illustrate it (Job 1910).

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), although Southern (1980) 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.