I'll tell you how it {raptor program} began: first came a bird
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Pacific Raptor Report↗
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Beak deformities in Buteo jamaicensis (Red-tailed Hawk) signal possible emergence of avian keratin disorder among raptors
Beginning in the late 1990s, an unusual cluster of beak deformities was observed among Buteo jamaicensis (Red-tailed Hawk) in the Pacific coastal region of North America. However, information was not available to determine the scope of this problem nor to assess a potential link between beak deformities in hawks and avian keratin disorder (AKD), an emerging disease primarily among passerines that causes overgrowth of the keratinized layer of the beak. To help address these knowledge gaps, we compiled capture records, citizen science reports, and other available data from across North America. As part of a long-term raptor monitoring program in Washington, we detected anomalously high rates of beak deformities in 29% and other keratin abnormalities in an additional 19% of B. jamaicensis between 2014 and 2021. We also identified more than 100 other AKD-like cases in B. jamaicensis , largely clustered in the Pacific coastal region, with most reports from 2000 to present. Pathologic examination of affected hawks revealed gross and microscopic features consistent with AKD in passerines, while shared epidemiological patterns, including timing of emergence, provided further evidence that this disease may impact an ecologically diverse suite of species. We detected poecivirus, a novel avian virus implicated as a likely cause of AKD in Poecile atricapillus (Black-capped Chickadee), in 1 out of 10 swabs collected from live B. jamaicensis , with gross beak deformities, suggesting the possibility of a shared viral etiology across species. However, additional work would be needed to determine the underlying cause of beak deformities in and their potential impacts on B. jamaicensis . By documenting this cluster of beak deformities, we hope to raise awareness among the ornithological community, including raptor researchers, to better track current and future outbreaks of beak deformities and related conditions.
Ornithology↗
Does vegetation structure limit the distribution of Northern Goshawks in the Oregon Coast ranges?
Northern Goshawks (Accipiter gentilis) breed in a variety of forested areas throughout the Pacific Northwest. Nevertheless, they were only first found breeding in the Coast Ranges of Oregon in 1995, despite apparently suitable habitat and abundant prey. We document the rarity of goshawks in the Coast Ranges by reviewing previous and current survey results for nests of goshawks and other forest birds since the 1960s, examining sightings of goshawks since 1980 and reporting on a survey we conducted in 1994. We suggest that nesting goshawks are rare in the Coast Ranges because of the vegetative structure of the area and its influence on prey availability. ?? 1997 The Raptor Research Foundation, Inc.
Journal of Raptor Research↗
Probable causes of nesting failures in Oregon's bald eagle population
During the last 4 decades, numerous studies on a variety of raptor species have described breeding success and productivity, but few studies have reported the causes of nesting failures. Newton (1979:358) described causes of nesting failures for 6 species of raptors, but only 2 of these species (bald eagle [ Haliaeetus leucocephalus ], prairie falcon [ Falco mexicanus ]) inhabit North America. Assessing causes of nesting failures is difficult because some causes are easier to determine than others and some failures inevitably remain unexplained. The difference between the number of young produced/successful nest and occupied nest from 1979-1992 for Oregon's bald eagle population (Fig. 1) averaged 0.60 young/site and reflected the influence of nesting failures on productivity (young/occupied nest). Overall, the annual failure rate (% of occupied sites failing to produce young) averaged 40% (range = 34-49%) for this population from 1979-1992 and was higher than the 35% specified for recovery in the Pacific states (U.S. Fish and Wildl. Serv. 1986).
Oregon↗