The journeys of night-migrating birds are already fraught with danger. Light pollution adds yet another hazard beyond the increased risk of collisions with buildings or communication towers. According to a new study, birds attracted by the glow of artificial light at night are drawn into areas where they are also exposed to higher concentrations of airborne toxic chemicals. The study has just been published in the journal Global Change Biology.
"We examined the correlation between the concentration of airborne toxic chemicals, artificial light at night, and the weekly abundance of 165 nocturnally migrating songbird species," said lead author Frank La Sorte at the Cornell Lab of Ornithology. "What we found is that light pollution does indeed increase exposure to toxic chemicals when birds stop to rest during spring and fall migration. Surprisingly, we also found that exposure to toxic chemicals is high during the non-breeding season, a time when birds typically avoid light pollution."
The only time that did not reveal increased exposure to toxic chemicals was during the breeding season when songbirds typically nest in habitats away from areas of intense human activity.
Read more at: Cornell University
Townsend's Warbler (Photo Credit: Craig Kerns, Cornell Lab of Ornithology)
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