Electric Shock Injuries in a Harris's Hawk Population

Electrocution may be an important agent of mortality in many raptor populations, and has been implicated as a contributing factor in the endangerment of some species. In Tucson, Arizona U.S.A. the electrocution of Harris's Hawks (Parabuteo unicinctus) was reported in both the 1980s and 1990s. The latter report also described Harris's Hawks that survived electric shock injuries. From February 2003-May 2004, I captured and examined wild Harris's Hawks in Tucson to investigate whether electric shock injuries might be present in individuals that appeared healthy from a distance. I trapped 85 birds; seven exhibited definite electric-shock injuries, and seven exhibited suspected electric-shock injuries. One individual exhibited injuries not consistent with electric shock. I captured an equal number of males and females, but only one of the injured birds was a male. Females were significantly more likely to have injuries. Whether this difference reflects patterns of initial incurrence of injury, or of higher probability of survival after electric shock remains unresolved. As medium- and large-bodied raptors colonize urban areas where overhead electric systems tend to occur in high densities, those species may also incur increased risk of electrocution.