Population status

Sharp-shinned Hawk
(Accipiter striatus)

The Sharp-shinned Hawk is widespread in Canada, but somewhat uncommon. This species is considered difficult to survey during the breeding season (Bildstein and Meyer 2000); few are recorded on Breeding Bird Survey (BBS) routes in Canada. Still, BBS results suggest an increase in abundance of about 80% since about 1970 (all Bird Conservation Regions with reasonably reliable results are displayed below). However, the overall reliability of this assessment is considered medium because the BBS covers less than half of the species' breeding population and the estimated trends within Canadian regions rely on the species' range-wide trend (i.e., the average trend across the BBS survey area, including in the United States) since there are relatively few observations of the species in any one region. BBS results from throughout North America suggest that the continental population has also increased since the mid-1960s. It is interesting to note that Crewe et al. 2016 estimated trends during migration at Hawk Watch sites across the United States and a few sites in eastern Canada, and their results suggest that numbers of Sharp-shinned Hawks have decreased during migration in the Northeast and Gulf Coast of the U.S. over the short-term (2005-2016). However, it is difficult to determine how these results reflect on the status of Sharp-shinned Hawk populations in Canada, in part because the proportion of Canadian breeders migrating through these sites is unknown. Disagreement between these migration trend results and those from the BBS may also be due to changes in migration geography or behaviour in the species (Farmer et al. 2008). Because the Sharp-shinned Hawk was persecuted and affected by DDT (Farmer et al. 2008), resulting in low levels of abundance at the start of monitoring efforts, and its historical abundance remains unknown, a specific management goal relative to 1970 has not yet been set. However, with an increasing population trend, the Sharp-shinned Hawk's current population is at an acceptable level (see Canada graph below).

 

Population goal and acceptable levels of variation

Species/groupGoalLower levelUpper level
Sharp-shinned HawkTo be determined95th percentile of observed abundance (1970-2012)
Not applicable

Breeding Bird Survey (BBS) - Canadian analysis

Additional information on: Breeding Bird Survey (BBS) - Canadian analysis

Table 1: Population trends by geographic area
Geographic areaTime Period Table 1 - footnote 1 Annual trend Table 1 - footnote 2 Limits
LowerUpper
Canada Select to view graph of the geographic area: Canada 1970-2016; Breeding Bird Survey (BBS) - Canadian analysis1970-20161.30.52
Lower Great Lakes / St. Lawrence Plain Select to view graph of the geographic area: Lower Great Lakes / St. Lawrence Plain 1970-2016; Breeding Bird Survey (BBS) - Canadian analysis1970-20162.10.43.8
North America Select to view graph of the geographic area: North America 1970-2016; Breeding Bird Survey (BBS) - Canadian analysis1970-201610.31.5
 

References

  • 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. Auk 107:96-109.
  • Bildstein, K.L. and K. Meyer. 2000. Sharp-shinned Hawk (Accipiter striatus), The Birds of North America Online (A. Poole, Ed.). Cornell Lab of Ornithology, Ithaca, New York. Bildstein, K.L. and K. Meyer. 2000. Sharp-shinned Hawk (Accipiter striatus), The Birds of North America Online (A. Poole, Ed.). Cornell Lab of Ornithology, Ithaca, New York. (Link)
  • Crewe, T., P. Taylor, D. Lepage, L. Goodrich, J. Brown, and J. Sodergren. 2016. The Raptor Population Index, 2016 Analysis Methods and Trend Results. Crewe, T., P. Taylor, D. Lepage, L. Goodrich, J. Brown, and J. Sodergren. 2016. The Raptor Population Index, 2016 Analysis Methods and Trend Results. (Link)
  • Farmer, C.J., L.J. Goodrich, E. Ruelas and J. Smith. 2008. Conservation status of North American raptors. pp. 303-420 in: State of North America's Birds of Prey. Bildstein, K. L., J. P. Smith, E. Ruelas Inzunza, and R. Veit, Eds. Nuttall Ornithological Club and American Ornithologists' Union, Series in Ornithology, No. 3, Cambridge, MA and Washington, DC.
  • Farmer, C.J., L.J. Goodrich, E. Ruelas Inzunza, and J.P. Smith. 2008. Conservation status of North America's birds of prey. pp. 303-419 in: State of North America's Birds of Prey. K.L. Bildstein, J.P. Smith, E. Ruelas Inzunza, and R.R. Veit (Eds.). Nuttall Ornithological Club, Cambridge, MA, and American Ornithologists' Union, Washington, D.C., USA.
  • Snyder, N.F.R., H.A. Snyder, J. Lincer and R.T. Reynolds. 1973. Organochlorines, heavy metals and the biology of North American accipiters. Bioscience 23:300-305.
  • Viverette, C.B., S. Struve, L.J. Goodrich and K.L. Bildstein. 1996. Decreases in migrating Sharp-shinned Hawks at traditional raptor-migration watchsites in eastern North America. Auk 113:32-40.