Summer Habitat Selection of the Lower Colorado River Valley Population of Greater Sandhill Cranes

Abstract Identifying habitat selection and use is important to understand in wildlife management because it informs habitat manipulations, conservation efforts, and species distribution. Habitat selection by sandhill cranes (Antigone canadensis) has been studied primarily on overwintering areas and a few summering locations. Summer habitat selection by the Lower Colorado River Valley Population of greater sandhill cranes (A. c. tabida) in the Intermountain West is not widely known, but has been identified as an information need by many wildlife management agencies. We captured and attached satellite platform transmitter terminals to 21 adult sandhill cranes on Cibola and Sonny Bono Salton Sea National Wildlife Refuges in Arizona and California, and private lands in California and Idaho. Home ranges of all marked cranes (50% core area: x̄ = 525.4 ha, SE = 155.6; 99% isopleth: x̄ = 6,476.5 ha, SE = 1,637.5) were similar to other studies on summering grounds. Resource analysis indicated that marked sandhill cranes used wetland habitats in greater proportion than their availability for both nocturnal and diurnal locations at the population level, by individuals within the entire landscape, and by individuals within their core area. Wetland habitats consist of ∼7% of the available habitat. Within the Wetland category, the Temperate Flooded and Swamp Forest level (a Formation level in the National Vegetation Classification system) was the most important to summering Lower Colorado River Population sandhill cranes. Wetland managers can concentrate their efforts for conservation, enhancement, and restoration on these type of wetlands to ensure the sustainability of this small population of sandhill cranes.