2010 Breeding Bird Surveys on the Idaho National Laboratory Site

Abstract

birds, but the number of species (i.e., species richness) was lower than the 23-year average of 58. Compared with past surveys, we observed similar patterns of bird abundance among those species that are typically the most numerous. In 2010, the six species that were surveyed in greatest abundance were the horned lark (Eremophila alpestris, n = 1,447), western meadowlark (Sturnella neglecta, n = 927), Brewer’s sparrow (Spizella breweri, n = 772), sage sparrow (Amphispiza belli, n = 520), Franklin’s gull (Larus pipixcan, n = 520), and sage thrasher (Oreoscoptes montanus, n = 469). During 24 years of breeding bird surveys on the INL Site, with the exception of the Franklin’s gull, these species have been the five most abundant 19 times, and in the remaining five years they were among the six most abundant species. Considering declines reported in populations of sagebrush-obligate species throughout the intermountain west, this trend indicates that the quality of sagebrush-steppe habitat on the INL Site remains stable. Although three new species were added in the past three years to the list of birds that have been observed at least once during BBS on the INL Site, no new observations were made in 2010. Two species were observed during the surveys that had been recorded in ≤ 3 of the past 23 years. These include yellow warbler (Dendroica petechia) and great blue heron (Ardea herodias). Species observed during the 2010 BBS that are considered imperiled or critically imperiled in Idaho include the Franklin’s gull (n = 520), burrowing owl (Athene cunicularia, n = 3), greater sage-grouse (Centrocercus urophasianus, n = 1), and grasshopper sparrow (Ammodramus savannarum, n = 1). GSS-ESER-146