Introduction

Many summer visitors to the interior of western North America are puzzled when, hiking along the shore of a salt lake, a prairie slough, or an alpine tarn, they hear above them the sound of the sea. Looking up, they may be further surprised when they see a gull soaring, its white underparts gleaming from the reflected light of the water or salt flat below. This gull, far from the ocean, is likely breeding on islands in a nearby lake, for the California Gull is a breeding bird of inland seas.

Although it spends its winter months in a long, slow journey up and down the Pacific Coast, its breeding habits set the California Gull apart from the other white-headed gulls that are its closest relatives. Its populations survive, often in arid environments, by following the rise and fall of lake levels throughout the interior western region of North America from Mono Lake, California, in the south to Lac la Martre, Northwest Territories, in the north, and as far east as western Manitoba. Wherever there are islands, these gulls can nest, sometimes subsisting on food in the lakes on which they breed, or more often combing the surrounding croplands, deserts, or mountains for sufficient food to feed their young. In the far north they mix with breeding Herring Gulls (Larus argentatus), and throughout all but the southern third of their range they mix with Ring-billed Gulls (L. delawarensis). They generally do not hybridize with either of these species, and they excel at getting by in environments that are too low in productivity to support these congeners.

A gilded gull statue in Salt Lake City’s Temple Square commemorates this gull’s role in ridding early Mormon crops of plagues of grasshoppers. Although these golden memories may have been tarnished somewhat by more recent depredations on the region’s cherry crops, the California Gull still enjoys good will throughout most of its nesting range.