Great Salt Lake Shorebirds, Their Habitats, and Food Base

Abstract

Every year millions of shorebirds representing 42 species congregate on Great Salt Lake (GSL). It is one of the largest concentrations of shorebirds on Earth, and yet, compared to waterfowl and colonial nesting species at GSL, they have received relatively little attention. Some shorebirds nest and rear young, but many more use the lake as a fueling stopover during migration with some departing flights lasting thousands of nonstop kilometers. Three ecological parameters determine whether or not any given location is suitable shorebird habitat: water depth, type and extent of vegetation, and type of food items available. Although shorebirds are opportunistic, each species shows a preferential niche along the intersection of these parameters, which do not form distinct units but lie along overlap** continuums. We explain these continuums and describe how, in each specific shorebird habitat, salinity is a driver for both vegetation and macroinvertebrates, the primary food source. Playas and mudflats are important components of shorebird habitat, but the characteristics that define these features in the landscape have been mired in confusion. We clarify these major components of the GSL ecosystem. Finally, we provide species accounts for each of the 42 species of shorebird while at GSL, detailing status, abundance, range, and timing of arrival and departure and ecological preferences.