Raptor Electrocutions and Associated Fire Hazards in the Snake River Birds of Prey National Conservation Area

In 1999, we began an assessment of raptor electrocutions on power lines in and near the Snake River Birds of Prey National Conservation Area in southwestern Idaho. We produced a distribution line map of the study area in 1999, selected study segments, and began monthly searches for dead raptors along 19 segments totaling 61.2 linear km. From January-December 2000, we continued sampling at all 19 study segments. During initial searches in 1999, we found the remains of 24 dead birds below power poles. We found partially intact skeletons, scattered bones, and feathers of at least 23 individuals, and one intact golden eagle that had been electrocuted. In 2000, we found the remains of 23 additional birds along power lines in the study area, including 12 intact carcasses. Remains identified to species included 6 common ravens (Corvus corax), 1 bald eagle (Haliaeetus leucocephalus), 3 red-tailed hawks (Buteo jamaicensis), 2 rough-legged hawks (Buteo lagopus), 1 barn owl (Tyto alba), and 1 short-eared owl (Asio jlammeus). One common raven showed signs of electrocution. Twenty one sets of remains were found below 20 poles. Two birds also were found midspan between poles and may have been wire-strike victims. We found dead birds below 19 tangent poles and 1 pole in a dead end position. Pole-top configurations included simple crossarm, underbuilt, and compact designs. Additional hardware items on some poles included exposed jumper wires, transformers, capacitors, and electrical switches of several kinds. In 2001, we will continue sampling study segments each month. This spring, we will necropsy all intact carcasses recovered to date for which cause of death is unknown. Also, in 2001, we will initiate a carcass removal study to determine if scavenging will affect estimates of electrocution rates.