Habitat Selection of Spotted Sandpipers (Actitis macularius) and Killdeer (Charadrius vociferus) on the Elwha River

We studied the responses of spotted sandpipers (Actitis macularius) and killdeer (Charadrius vociferus) to restoration associated with dam removals on the Elwha River, Washington. As many dams approach the end of their useful lives, the need to understand responses and implications of shorebirds and other wildlife returning post dam removal sites is becoming increasingly important. Sandpipers are among the first wildlife to return to restoration sites exposed when reservoirs are drained, while killdeer are a species in the Elwha known to assist in the dispersal of disseminules and gastropods. Specifically, we investigated spotted sandpiper and killdeer distributions and habitat selection relative to the availability of five kinds of substrates. We tested the hypothesis that shorebird habitat selection is determined by substrate texture, with greater use of cobbles and gravel than silt, sand, and vegetated areas. We recorded spotted sandpipers and killdeer locations and associated substrates in open areas along the larger of the former Elwha reservoirs and a matched valley upriver from direct dam effects. We determined substrate extent and distributions using a systematic sampling grid anchored by a random starting point. We used logistic regression models to calculate substrate resource selection functions. Our results reveal a reciprocal relationship of spotted sandpiper and killdeer in Elwha restoration. Shorebirds have benefited from extensive open habitats created by dam removal, and they may enhance restoration by distributing organic matter and nutrients to substrates lacking those materials