Summary
This is the paper that started the big debate, and inspired petitions to list the goshawk. The author aimed to experimentally test the adequacy of nest habitat buffers from maintaining goshawk reproduction

States:
"nests of northern goshawks are usually found within dense stands of large trees; thus, their nesting habitat may be adversely affected by timber harvest (cites others)."

This study's goal was to "experimentally test the adequacy of nest habitat buffers for maintaining goshawk reproduction" and to analyze "goshawk fidelity over time to nest trees and nesting stands."

"Nest buffers, large or small, did not maintain goshawk reproduction. The recorded occupancy rates were 75-80% lower where timber harvest occurred around buffers, and nestling production was 94% lower."

Recommendations on Habitat Management
"Attention needs to be given to the general habitat over the entire foraging area of a pair of goshawks, because nest buffers by themselves are ineffectual. After partial harvesting over extensive locales around nest buffers, reoccupancy decreased by an estimated 90% and nesting production decreased by an estimated 97%. Decreases were probably due to increased competition from open-forest raptors, as well as changes in hunting habitat and prey abundance."

"Goshawk nesting density appears to be closely associated with dense overstories and open understories. Goshawk habitat may therefore be improved by silvicultural activities which reduce the densities of shrubs, saplings, and small poles, while maintaining or enhancing the canopy of large trees."

Recommends maintaining "much prime goshawk habitat (dense large trees with open understories within foraging range of nests (at least 2000 ha)."

Summary
"The North Kaibab Ranger District provided small habitat buffers (1.2 to 2.4 ha) or large buffers (16 to 200 ha) around all goshawk nests located prior to timber harvests. Partial harvesting removed one-third of the trees from 80% of the stands in treatment locales. Contiguous control locales were unharvested blocks exceeding 4700 ha. I compared occupancy of individual nest trees as well as occupancy and production of goshawk territories, which typically included 3 nests."

"Reoccupancy of control nest trees, from 1985 to 1987, was as high for nest trees discovered during the 1970's as for those discovered during the early 1980's. Nest trees were sometimes reoccupied after former nests had totally disappeared."

"Even with nest buffers, recorded reoccupancy dropped by 80% and recorded nestling production dropped by 94% following logging. The true decreases were greater. Other raptors replaced goshawks in most logged territories but in no control territories. Goshawk foraging habitat is degraded by activities which decrease the canopy of large trees and promotes the development of a dense brush, sapling, or pole understory."

"Timber harvesting on the North Kaibab Ranger District caused goshawks to decline from and estimated 260 nesting pairs to approximately 60 pairs by 1988."

Note
This paper has received much criticism and has fueled a major debate over goshawk conservation. See Kennedy (1997), Kennedy (1998), Smallwood (1998), Crocker-Bedford (1998), and especially DeStefano (1998) for more.