Gregory D. Hayward

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Iverson, George C.; Hayward, Gregory D.; Titus, Kimberly; DeGayner, Eugene; Lowell, Richard E.; Crocker-Bedford, D. Coleman; Schempf, Philip F.; Lindell, John. 1996. Conservation assessment for the northern goshawk in southeast Alaska. Gen. Tech. Rep. PNW-GTR-387. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research(More)
Establishing species conservation priorities and recovery goals is often enhanced by extinction risk estimates. The need to set goals, even in data-deficient situations, has prompted researchers to ask whether general guidelines could replace individual estimates of extinction risk. To inform conservation policy, recent studies have revived the concept of(More)
—Habitat connectivity and corridors are oft en assumed to be critical for the persistence of patchily distributed populations, but empirical evidence for this assumption is scarce. We assessed the importance of connectivity among habitat patches for dispersal by a mature-forest obligate, the Boreal Owl (Aegolius funereus). Boreal Owls demonstrated a lack of(More)
We studied resource partitioning among the forest owls in the River of No Return Wilderness, Idaho, during the winter and spring of 1980 and 1981. The owl assemblage consisted of five abundant species: pygmy (Glaucidium gnoma), saw-whet (Aegolius acadicus), boreal (A. funereus), western screech (Otus kennicottii), and great-horned (Bubo virginianus).(More)
Boreal owls Aegolius funereus (referred to as Tengmalm’s owls in Europe) breed in boreal forests throughout the Holarctic region and in high-elevation subalpine forests further south. They are currently classified as seven subspecies; six found throughout Eurasia, and one in North America. The geographic distribution of boreal owls in North America and(More)
Introductions of exotic species pose a significant threat to the persistence of many native populations, including many inland fishes. In 1994, piscivorous lake trout (Salvelinus namaycush) were discovered in Yellowstone Lake, Yellowstone National Park, Wyoming, USA, one of the last strongholds of the native Yellowstone cutthroat trout (Oncorhynchus clarki(More)
Wildlife conservationists design monitoring programs to assess population dynamics, project future population states, and evaluate the impacts of management actions on populations. Because agency mandates and conservation laws call for monitoring data to elicit management responses, it is imperative to design programs that match the administrative scale for(More)
Extra-pair fertilizations (EPFs) occur in over 86% of passerine species that have been studied but only in about 45% of nonpasserine birds (Westneat and Sherman 1997). EPFs have been documented at low rates in some diurnal raptors (Korpimäki et al. 1996, Negro et al. 1996) and owls might be expected to show similarly low rates due to their similar ecologies(More)
1 USDA Forest Service, Rocky Mountain Research Station, Fort Collins, CO 80526, USA 2 USDA Forest Service, Alaska Region, Anchorage, AK 99503, USA; and Department of Zoology & Physiology, University of Wyoming, Laramie, WY 80271, USA 3 Department of Environmental Science, Policy & Management, University of California, Berkeley, CA 94720, USA 4 School of(More)
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