IUCN 03/23/2021 – Least Concern (LC)

U.S. and Canada Conservation Status: Listed as endangered in Puerto Rico. Critically imperiled in 6/66 states and provinces (CT, MD, NJ, PA, RI, WV). Imperiled in 9/66 states and provinces (NM, OK, PA, SD, TN, VT, WA, WI, WY). Vulnerable in 28/66 states and provinces. Apparently secure in 9/66 states and provinces. Secure in 0/65 states and provinces.

The data used in this figure are listed above. These data were compiled from NatureServe and the U.S. Fish and Wildlife Service.

The Northern Goshawk is not listed as a Bird of Conservation Concern as of 2021. The species is protected under the Migratory Bird Treaty Act (MBTA) and is listed in the US Fish and Wildlife Birds of Management Concern for the Queen Charlotte Goshawk subspecies as of 2011. The Queen Charlotte subspecies is located in temperate rainforest archipelagos of Southeast Alaska and British Colombia.

In North America, from Western Alaska to the Atlantic region of Canada and south to California and Western Texas, excluding the Southeastern US. They are also found in parts of Northwestern Mexico. They are partial migrants and can winter throughout their breeding range with can include the Great Plains and some Southeastern states in the US.

Occupies large tracts of boreal and temperate forests throughout the Holarctic. Northern Goshawks prefer forests with large trees on moderate slopes with open understories, nesting in coniferous, deciduous, or mixed-pine forests. They hunt in forests and nearby open habitat (Squires et al, 2020).

Density of breeding pairs is low and difficult to census due to their use of large, forested habitats. Migration counts and Christmas Bird Counts can be difficult to interpret for this species because of over all lower numbers and their irruptive migratory behavior. Migration counts at Hawk Mountain Sanctuary recorded all time lows in the late 1930s to the early 1950s before gradually increasing in the 60s. General increases were observed during the DDT era (1946-1972) which is inconsistent with declines observed in other species during that time, however human persecution reduced numbers prior to the launch of raptor conservation efforts in the 1950s. Counts of migrants in Utah, Nevada, and New Mexico suggested a 4% decline per year between 1983 and 1991. Similar declines over the same time span were observed in the Eastern US, notably at Hawk Mountain Sanctuary (Bednarz et al, 1990). Migration counts have continued to decline at Eastern and Midwestern sites. Although the maturation of regenerated forests correlating with some range expansion of Northern Goshawks in the Northeastern US was noted from the mid-1980s to mid-1990s, their range has again retracted over the last decade in Pennsylvania and other Northeastern states. Christmas Bird Count data has reported between 2-8% declines annually over the last decade in the Midwest and Boreal Forest regions of the US and Canada, except for Alaska, Yukon, Quebec, and Newfoundland.

These maps summarize the latest RPI trend analyses for count sites throughout North America.

Find the interactive version of the Christmas Bird Count (CBC) maps here.

BBS: The Breeding Bird Survey has recorded a survey wide decline of Northern Goshawks from 1966 to 2019, with states and provinces showing a similar pattern of decline to the Christmas Bird Count and RPI trends. However, many of the states and provinces are flagged by USGS to have low credibility for this species survey.

Some possible reasons for Northern Goshawk population declines include loss of forest habitat in the boreal region due to logging, as well as environmental contaminants and infectious disease. West Nile virus has increased in Canada and the Northeastern United States. Northern Goshawks are vulnerable to the virus, which often results in mortality (Saito et al, 2007). Declines in avian prey and increased use of chemicals in northern forests could also play a role (Gray, 2013). Recent increases in wildfire frequency and intensity may also impact Western populations but more research is needed in relation to wildfire impacts on raptors. Forest fragmentation can allow increased nest predation by Great Horned Owls, fishers and other species. Additional research is needed to determine the impact of interspecific competition and predation.

Habitat loss is considered the primary threat for Northern Goshawks. They prefer large tracts of contiguous old forest containing large trees for breeding. They often hunt in forest clearings or cuts. Studies have shown that over 1.6 million acres of boreal forest has been lost due to logging in the last three decades which has effected nesting distribution. Nests are frequently destroyed by logging and abandonment has been observed due to timbering and logging activities within 50-100 meters of the nest, even with 20 day old nestlings. Declines in migrants at Western count sites have been attributed to an increase in deforestation. Some expansion in distribution was noted in Connecticut, New York, Pennsylvania, Michigan, and Massachusetts from the mid-1980s to mid-1990s, due to the maturation of regenerated forests. However, during 2009 to 2019, Northern Goshawk nesting range retracted in Pennsylvania and neighboring states. The effects of forest fragmentation and structural changes in forests has not been studied but could increase their exposure to nest predators. In northeastern forests, Northern Goshawks also may be affected by the cycling of the eastern spruce budworm (Choristoneura fumiferana), a native species of moth which defoliates spruce trees. The widespread practice of aerial spraying for spruce budworm to protect the forest for future logging has been observed to coincide with the decrease of some songbird populations such as evening grosbeaks, which are known spruce budworm specialists. Spruce budworm outbreak severity and length are expected to increase with predicted climate increases in the next 20 years. More research is needed to explore these relationships. The impact of the overall increase in both number of wildfires and fire severity in Western North America on raptor populations requires further investigation. These changes can result in profound changes in the ecosystem, including vegetation shifts, invasive species, and a decrease in biodiversity. Some preliminary research has shown raptors may not nest after a fire, which suggests raptors have experienced further loss of usable habitat due to increased fires in the West (Gao, 2020).

Some have speculated a possible correlation between the extinction of the passenger pigeon and declines in the Northern Goshawk population in North America. Northern Goshawk diet includes large passerines, woodpeckers, game birds, and corvids as well as tree squirrels, rabbits, hares, and occasionally reptiles. In Pennsylvania, Northern Goshawks are known to prey on Ruffed Grouse, with both species showing concerning declines in the state recently. Increased grouse mortalities have been attributed to West Nile virus (see below). However, goshawks also feed on abundant species such as crows, jays, and squirrels. Management recommendations describe ideal nesting habitat with an emphasis on forest conditions that support diverse prey populations.

West Nile virus (WNV) first reached the United States in New York in 1999 and has since spread across the continent. West Nile virus is a zoonotic disease that infects most avian species as well as horses and humans. The primary vectors for WNV are mosquito species Culex restuans and Culex pipiens, while many avian species serve as reservoirs. Northern Goshawks infected with the virus present neurologic symptoms and mortality. In a 2018 study in Ontario, 13% of Northern Goshawk mortalities were contributed to WNV. In Europe, WNV mortality is a commonly associated with Northern Goshawks. Northern Goshawks are most commonly infected with WNV through a mosquito bite or through feeding on infected birds (Vidaña et al., 2020). Northern Goshawks may have a higher chance of exposure to the virus than other raptor species due to their consumption of common WNV reservoir species. Loss of prey species may also be connected to the introduction of WNV to the United States, especially in the case of Ruffed Grouse (Bonasa umbellus) in Pennsylvania (Bolgiano, 2019). More research is needed to determine the extent to which WNV has impacted raptor populations, including Northern Goshawks.

Literature Cited

Bednarz, J. C., D. Klem Jr., L. J. Goodrich, and S. E. Senner. (1990). Migration Counts Of Raptors At Hawk Mountain, Pennsylvania, As Indicators Of Population Trends, 1934-1986. The Auk, 107, 96–107.

Bolgiano, N. (2019). Evidence for West Nile Virus-Related Avian Declines in Pennsylvania. Pennsylvania Birds, 33(1), 2-11.

Boreal Logging Scars, Wildlands League. 2019. Executive Summary. https://wildlandsleague.org/media/LOGGING-SCARS-FINAL-Dec2019-Exec-Summary.pdf

Byholm, P., R. Gunko, D. Burgas, and P. Karell. (2020). ‘ Losing your home : temporal changes in forest landscape structure due to timber harvest accelerate Northern goshawk (Accipiter gentilis) nest stand losses ‘, Ornis Fennica, vol. 97 , no. 1 , pp. 1-11.

Farmer, C. J., and D. J. Hussell. (2008). The raptor population index in practice. State of North America’s birds of prey. Series in Ornithology, (3), 165-178.

Farmer, C. J., and J. P. Smith. (2010). Seasonal differences in migration counts of raptors: Utility of spring counts for Population Monitoring. Journal of Raptor Research, 44(2), 101–112. https://doi.org/10.3356/jrr-09-31.1

Fink, D., T. Auer, A. Johnston, M. Strimas-Mackey, O. Robinson, S. Ligocki, W. Hochachka, L. Jaromczyk, C. Wood, I. Davies, M. Iliff, and L. Seitz. (2021). eBird Status and Trends, Data Version: 2020; Released: 2021. Cornell Lab of Ornithology, Ithaca, New York. https://doi.org/10.2173/ebirdst.2020

Gao, J. (2020). (master’s thesis). Effects of Woolsey Fire on Nesting Territories of Southern California Red-Tailed Hawks (Buteo jamaicensis). Oregon State University. Retrieved 2022, from https://ir.library.oregonstate.edu/concern/graduate_projects/5d86p6213.

Gray, D. R. (2013). The influence of forest composition and climate on outbreak characteristics of the spruce budworm in Eastern Canada. Canadian Journal of Forest Research, 43(12), 1181–1195.

Master, L., D. Faber-Langendoen, R. Bittman, G. A. Hammerson, B. Heidel, L. Ramsay, K. Snow, A. Teucher, and A. Tomaino. (2012). NatureServe conservation status assessments: Factors for evaluating species and ecosystem risk. NatureServe, Arlington, Virginia.

Meehan, T.D., G. S. LeBaron, K. Dale, A. Krump, N.L. Michel, and C. B. Wilsey. (2020). Abundance trends of birds wintering in the USA and Canada, from Audubon Christmas Bird Counts, 1966-2019, version 3.0. National Audubon Society, New York, New York, USA.

Rosenberg, K. V., Dokter, A. M., Blancher, P. J., Sauer, J. R., Smith, A. C., Smith, P. A., Stanton, J. C., Panjabi, A., Helft, L., Parr, M., and Marra, P. P. (2019). Decline of the North American avifauna. Science, 366(6461), 120–124. https://doi.org/10.1126/science.aaw1313

Squires, J. R., R. T. Reynolds, J. Orta, and J. S. Marks (2020). Northern Goshawk (Accipiter gentilis), version 1.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.norgos.01

USFWS. 2014. Species Status Assessment for Species Northern Goshawk (Accipiter gentilis).

U.S. Fish and Wildlife Service. 2021. Birds of Conservation Concern 2021. United States Department of the Interior, U.S. Fish and Wildlife Service, Migratory Birds, Falls Church, Virginia. http://www.fws.gov/birds/management/ managed-species/birds-of-conservation-concern.php

Vidaña, B., N. Busquets, S. Napp, E. Pérez-Ramírez, M. A. Jiménez-Clavero, and N. Johnson. (2020). The role of birds of prey in West Nile virus epidemiology. Vaccines, 8(3), 550. https://doi.org/10.3390/vaccines8030550

Partners in Flight, Vanishing Habitats. https://partnersinflight.org/vanishing-habitats/

Learn more about this species natural history at All About Birds or at Hawk Mountain’s website.