Bird Species of Special Concern
Goshawk
The idea–
The Northern Goshawk (Accipiter gentilis) is designated as a Sensitive Species in a number of Forest Service Regions including northern Idaho and Montana. It is also identified as a Management Indicator Species (MIS) on many National Forests. In the Northern Region, it is classified as “Sensitive” Region-wide and is an “MIS” on all but the Bitterroot and Kootenai National Forests and the Dakota Prairie National Grasslands. We want to understand the geographic extent and environmental conditions that the bird is most likely to occupy.
Methods–
In the spring and summer of 2005, the Avian Science Center conducted a field survey of goshawks across the accessible portions in Region 1. The primary purpose of this survey was to use a statistically based approach to (1) estimate the rate of goshawk occupancy (frequency of goshawk presence) within a grid that approximates the territory size for this species and (2) better define and document the geographic distribution of goshawks across the Northern Region.
Results–
The maximum likelihood estimate of the proportion of primary sample units (PSUs) with goshawks present in road-accessible lands in the region is 0.39, with a 95% confidence interval of 0.29 to 0.50. This is based on visits to 114 PSUs that were distributed across 12 National Forests in the Region, resulting in 40 PSUs with goshawk detections on one or both visits. In addition to obtaining 40 detections out of the 114 PSUs sampled, crews located seven new goshawk nests.
Annual Reports or publications from this project–
Click to download the Final Goshawk report .
Funders–
USDA Forest Service Northern Region
Contact–
dr. richard hutto