The conservation status of northern goshawks in southeast Alaska is examined through developing an understanding of goshawk ecology in relation to past, present, and potential future habitat conditions in the region under the current Tongass land management plan. Forest ecosystem dynamics are described, and a history of forest and goshawk management in the Tongass National Forest is reviewed. Nearly 900,000 acres of the most productive old-growth temperate rain forest in southeast Alaska (public and private lands) have been harvested during the past 90 years and changed to early seral conifer forests. Goshawk habitat relations are described through a review of the goshawk literature. Significant preliminary findings of a habitat relation study in southeast Alaska include the following: goshawks select productive old-growth forests with > 60 percent of all adult goshawk telemetry relocations occurring in this cover type; nonforest, clearcut, and alpine cover types were least used and were avoided relative to their availability; and the median breeding season minimum convex polygon use areas of adult goshawks was about 10,000 acres. Goshawks predominantly use gentle slopes (70 percent of relocations) at elevations below 800 feet (54-74 percent of relocations); 24 percent of relocations occurred in riparian habitat zones, and nearly 20 percent of all relocations occurred within the beach fringe habitat extending 1,000 feet inland from the ocean shoreline. Goshawk nesting habitat is a nonrandom subset of the landscape with a significantly higher proportion of productive old-growth forest within a 600-acre analysis area surrounding known nests. The probability of persistence of goshawks has declined over the past 50 years owing to habitat loss and likely will continue to decline under current management plan regimes; however, the goshawk population likely is not in immediate peril. The predicted consequences of several alternative habitat management approaches are compared. This analysis suggests that long rotation forestry (e.g., 300 years) and uneven-aged silvicultural management may maintain habitat characteristics important to sustaining goshawk populations well distributed across the region. Although habitat reserves are not considered an essential component of a forest-wide goshawk conservation strategy, reserves, in combination with extended rotations, may be important where the intensity of past management actions has precluded the opportunity to attain a desired combination of forest age classes achieveable under long rotations. Revision efforts for the TLMP resumed in fall 1994 with a focus on five major land management issues considered to be inadequately addressed in the existing TLMP: wildlife viability, fish and riparian habitat, caves and karst, alternatives to clearcutting, and socioeconomic considerations. Goshawk conservation is an important component within the wildlife viability issue.Concern for goshawk population viability in southeast Alaska evolved during the past decade and culminated with th...
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We used feathers from adult Gyrfalcons (Falco rusticolus) molted in breeding territories and blood samples from nestlings to document nest-site fidelity and dispersal of breeding adults and juveniles at three areas 100-350 km apart in Yukon Delta National Wildlife Refuge, Alaska, 2003Alaska, -2007. We used genotypes from seven polymorphic microsatellite loci that provided a mean probability of identity of 0.91 xlO'. Breeding Gyrfalcons were highly faithful to study area and territory; we documented no dispersals of breeding birds among study areas and only one dispersal between territories. But their fidelity to nest sites was low; 22% of birds returned to the same nest site the following year Distance among alternate nests within a territory averaged 750 m and was similar for both sexes. Mean tenure in a territory was 2.8 years, similar for both sexes, and distributed bimodally with peaks at 1 and 4 years. Mean annual turnover rate at the Ingakslugwat Hills (Volcanoes) study area was 20%. We detected three young that established breeding territories at distances ranging from 0 to 254 km from their natal territory, representing 2.5% apparent recruitment. Gyrfalcons in the Askinuk Mountains study area were slightly but statistically significantly differentiated genetically from those in the Volcanoes and Kilbuck Mountain study areas. These data are the first published on the nest-site fidelity, breeding dispersal, and natal dispersal of the Gyrfalcon in North America and demonstrate the utility of noninvasive genetic sampling to greatly improve our understanding of avian dispersal and its underlying mechanisms.
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