Recovery Plan for the Northern Spotted Owl - DRAFT

Range, the Blue and Okanogan Mountains, and the Selkirk Mountains(Fleming 1987).Status.-Goshawks historically nested throughout the forested regions oftemperate North America. By the 1930s however, breeding populations in theeastern United States were much reduced (Bent 1937). The status of thegoshawk is not well known for much of the western United States. Mostauthors believe that the species has declined substantially since the turn of thecentury, primarily as a result of habitat loss attributed to intensive timberharvest. Bloom et al. (1985) estimated that goshawk populations in Californiahad decreased by 30 percent from historic levels by 1985, with continuingdeclines of approximately 1 percent per year. Mannan and Meslow (1984)speculated that goshawks could be extirpated from northeastern Oregonforests under timber management regimes that resulted in the liquidation ofmost of the old-growth forest in the area. Patla (1991) documented an 80percent decrease in occupancy rates for goshawks in habitat adjacent to timbersales, despite the establishment of buffers around the immediate nest sites.Buffers apparently were unsuccessful in Arizona as well, as Crocker-Bedford(1990) suggested declines of as much as 90 percent in nest occupancy andproductivity for an isolated population in northern Arizona.The goshawk is classified as "critical" on the Oregon sensitive species list."Critical" indicates a species for which listing is pending or for which listingmay be appropriate if immediate conservation actions are not taken (OregonDepartment Fish and Wildlife 199 lb). The states of Washington and Californiaalso list the northern goshawk as a candidate for state listing and a sensitivespecies, respectively (Washington Department Wildlife 199 lb, California Fishand Game 1990). In July 1991, a petition was filed with the FWS for emergencylisting of an isolated population of goshawks in the southwestern UnitedStates. More recently, the species has been petitioned for listing throughoutthe western United States. The goshawk is a management indicator species forold-growth dependent species on the Deschutes, Fremont, Wallowa-Whitman,and Winema National Forests in Oregon, and the Inyo, Klamath, Six Rivers,and Shasta-Trinity National Forests in California.Natural history and habitat associations.-Goshawks may be found indeciduous and coniferous forest types, where they typically select nest sites indense, single-storied mature to old-growth forests with high canopy closureand poorly developed understories. Nest trees tend to be significantly larger indiameter than those of the surrounding stand: nest stands, in turn, often aremore dense and include larger diameter stems than adjacent forest stands(Buchanan 1991, Fleming 1987). Snags, stumps, and down logs are importantas plucking perches, which are generally located within 55 yards of the nest.This general characterization holds for goshawk nests from the OlympicPeninsula (Fleming 1987), south to California and northern Arizona (Austin1989, Reynolds 1989, Hall 1984), and east into the northern Rockies (Haywardetal. 1990).Ongoing research and decades of nest records and incidental sightings indicatethat goshawks in western North America find optimal habitat in mature andold-growth coniferous forests. The vertical and horizontal structure of olderforests contributes to accessible prey and nest sites (trees) substantial enoughto support the bulky stick nest. The strength of the association may vary. InOregon, all but one of 74 nests located by Reynolds were situated in densemature or old-growth stands (Reynolds and Wight 1978). Loss of breeding andwintering habitat resulting from harvest of old-growth, reproductive failure,and human disturbance were the primary limiting factors for goshawks(Reynolds 1989). The liquidation of older forests and increasing fragmentationof suitable habitat are probably the most significant threats to goshawks.385