Justification of Red List Category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (extent of occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
The European population is estimated at 37,200-79,200 pairs, which equates to 74,400-158,000 mature individuals (BirdLife International 2015). Europe forms approximately 15% of the global range, so a very preliminary estimate of the global population size is 496,000-1,050,000 mature individuals, although further validation of this estimate is needed. Rich et al. (2004) estimated the global population to number > c.500,000 individuals which would equate to approximately 333,000 mature individuals. The population is therefore placed in the band 300,000-1,000,000 mature individuals.
This species has had stable population trends over the last 40 years in North America (data from Breeding Bird Survey and/or Christmas Bird Count: Butcher and Niven 2007). In Europe the population size is estimated to be fluctuating (BirdLife International 2015).
In Sweden many birds were recovered in the area where they were rung due to hunting; illegal shooting may be a problem in some areas, including the U.S.A (Orta et al. 2015). It also suffers mortality from collisions with cars, electrocution from powerlines (Mebs and Schmidt 2006) and accidental capture in traps set for fur-bearing mammals (Orta et al. 2015). The species may also suffer reduced reproductive success from fluctuating weather caused by climate change (Pokrovsky et al. 2012). In the past, organochlorine pesticide treatments were thought to pose a threat to the species in the U.S.A. (Henny et al. 1984).
Text account compilers
Ekstrom, J., Butchart, S. & Ashpole, J
BirdLife International (2019) Species factsheet: Buteo lagopus. Downloaded from http://www.birdlife.org on 17/11/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 17/11/2019.