Long-billed curlews on the Yakima Training Center: Information for base realignment

Abstract

This report summarizes and discusses the results obtained during 1992 from the study of long-billed curlews on the Yakima Training Center (YTC), which Pacific Northwest Laboratory conducted for the US Department of the Army. This study was initiated to provide basic ecological information on YTC long-billed curlews (Numenius americanus). The long-billed curlew is a relatively common spring and summer resident on the YTC. However, other than casual observations, very little is known about the distribution, density, reproductive success, and habitat requirements for this species on the YTC. Until recently the long-billed curlew was a US Fish and Wildlife Service candidate for listing as threatened or endangered; however, on November 21, 1991 it was down-listed to Class IIIc. The Washington Department of Wildlife lists the long-billed curlew as a ``species of special concern.`` Specific objectives of this study were to (1) locate nesting areas, (2) locate brood-rearing areas, (3) evaluate habitat requirements, (4) determine diet, (5) evaluate response to troop activities, (6) evaluate the impact of livestock grazing, (7) estimate the population size, and (8) estimate recruitment rates. Six curlews (four females and two males) were captured and fitted with radio transmitters. These birds were relocated to obtain nesting, habitat use, and feeding information. Road surveys conducted over most of the YTC provided information on the bird`s general distribution, habitat requirements, and nesting and brood-rearing areas.