Electrocution isn’t the Main Thing Killing Birds Along Power Lines

By: Annabelle Ma

Though birds get electrocuted by power lines, people shooting at birds while they are perched on them is more of an issue. According to a survey of five sites in the western United States, two-thirds of the birds found under power lines had been shot.

Birds found dead under power lines are often presumed to have died from electrocution, especially if they are singeing, said Eve Thomason, a wildlife biologist at Boise State University in Idaho.

However, many animals may have been injured or killed even before getting zapped.

“We really need X-rays to understand fully what may have happened,” said Ms. Thomason, who used to study the effect of power lines on birds.

In a study conducted by Ms. Thomason and her colleagues, they walked along 112 miles of power lines, collecting a total of 410 dead birds. They brought these birds back to their lab to analyze their cause of death.

“Most of them were coming back with bullet fragments in them or shotgun pellets,” Ms. Thomason said. Of the 175 birds that they were able to determine a cause of death, 66 percent had been shot, the scientists reported.

The number of birds shot at each site varied considerably. At two of the sites they visited, all of the birds died due to gunshots, while at another site only 39 percent of deaths were related to gunshots and a similar percentage of deaths were from electrocution.

Most of the dead birds were ravens and raptors (hawks, eagles, etc.). Killing these animals is illegal and endangers the population of these species. With the effort from state fish and wildlife agencies, researchers have assumed that the number of shootings has declined, but clearly, their assumption was wrong.

Some places are struggling with the problem of electrocution. For example, in Texas and New Mexico, 34 percent of eagles that leave their nests get electrocuted in the first year of their lives.

Researchers are still looking for the reason why people want to shoot at protected birds. Pete Marra is an ornithologist at Geogetown University, who studied the sharp decline of the bird population before but wasn’t part of this study. “What’s essential in order to stop the decline of birds is to understand what’s causing the declines of birds,” he said.