Illegal Shooting is Now a Leading Cause of Death of Birds Along Power Lines in the Western USA

Human actions, both legal and illegal, affect wildlife in many ways. Inaccurate diagnosis of cause of death undermines law enforcement, management, threat assessment, and mitigation. We found 410 dead birds collected along 196 km of power lines in four western USA states during 2019–2022. We necropsied these carcasses to test conventional wisdom suggesting that electrocution is the leading cause of death of birds at electrical infrastructure. Of 175 birds with a known cause of death, 66% died from gunshot. Both raptors and corvids were more likely to die from gunshot than from other causes, along both transmission and distribution lines. Past mitigation to reduce avian deaths along power lines has focused almost exclusively on reducing electrocutions or collisions. Our work suggests that, although electrocution and collision remain important, addressing illegal shooting now may have greater relevance for avian conservation

Illegal Killing of Nongame Wildlife and Recreational Shooting in Conservation Areas

Illegal killing of nongame wildlife is a global yet poorly documented problem. The prevalence and ecological consequences of illegal killing are often underestimated or completely unknown. We review the practice of legal recreational shooting and present data gathered from telemetry, surveys, and observations on its association with illegal killing of wildlife (birds and snakes) within conservation areas in Idaho, USA. In total, 33% of telemetered long‐billed curlews (Numenius americanus) and 59% of other bird carcasses found with known cause of death (or 32% of total) were illegally shot. Analysis of spatial distributions of illegal and legal shooting is consistent with birds being shot illegally in the course of otherwise legal recreational shooting, but snakes being intentionally sought out and targeted elsewhere, in locations where they congregate. Preliminary public surveys indicate that most recreational shooters find abhorrent the practice of illegal killing of wildlife. Viewed through this lens, our data may imply only a small fraction of recreational shooters is responsible for this activity. This study highlights a poorly known conservation problem that could have broad implications for some species and populations of wildlife

Assessing Illegal Shooting of Birds Along Power Lines

Birds found dead near power lines typically are assumed to have died from electrocution. However, birds die from many causes, and inaccurate diagnosis of cause of death undermines law enforcement, management, threat assessment, and mitigation. We used field and necropsy data from dead birds collected along 196 km of power lines in four western USA states in 2019 – 2022 to test the assumption that electrocution is the leading cause of death of birds on power lines. Of 175 birds with a known cause of death, 66% died from gunshot, whereas only 17% died from electrocution or by trauma. To address the issue, law enforcement and resource managers need to understand where, when, and why illegal shooting occurs. Therefore, we examined spatial and temporal patterns in illegal shooting along power lines in the Morley Nelson Snake River Birds of Prey National Conservation Area in Idaho, USA, in 2021-2022 to evaluate two hypotheses for potential drivers of illegal shooting of protected nongame birds. These hypotheses were (a) that illegal shooting was the consequence of a premeditated activity; and (b) that illegal shooting was an opportunistic event associated with other legal recreational activity (these two hypotheses are not mutually exclusive). Shot birds were often found in clumped spatial patterns, with many birds shot in relatively short timespans. At times there were multiple shot birds beneath the same power pole, at contiguous poles, and along consecutive segments of power lines. These findings are consistent with the hypothesis that illegal shooting was premeditated. There was also strong evidence that illegal shooting was associated with legal recreational activity. For example, most illegal shooting occurred in the spring, which coincided with a peak period of legal recreational shooting, and illegal shooting ceased during periods with low recreational shooting activity. Furthermore, the locations of some illegally shot birds were in recreational shooting “hotspots.” Although past mitigation to reduce avian deaths along power lines has focused almost exclusively on reducing electrocutions and collisions, today, addressing illegal shooting may have greater relevance for conservation and design of electrical infrastructure

Dataset for 2020 Illegal Killing of Non-Game Wildlife and Recreational Shooting in Conservation Areas

Illegal killing of non-game wildlife is a global yet poorly documented problem. The prevalence and ecological consequences of illegal killing are often underestimated or completely unknown. We review the practice of legal recreational shooting and present data gathered from telemetry, surveys, and observations on its association with illegal killing of wildlife (birds and snakes) within conservation areas in Idaho, USA. In total, 33% of telemetered long-billed curlews (Numenius americanus) and 59% of other bird carcasses found with known cause of death (or 32% of total) were illegally shot. Analysis of spatial distributions of illegal and legal shooting is consistent with birds being shot illegally in the course of otherwise legal recreational shooting, but snakes being intentionally sought out and targeted elsewhere, in locations where they congregate. Preliminary public surveys indicate that most recreational shooters find abhorrent the practice of illegal killing of wildlife; viewed through this lens, our data may imply only a small fraction of recreational shooters are responsible for this activity. This study highlights a poorly known conservation problem that could have broad implications for some species and populations of wildlife