Noise-Induce Hearing Loss (NIHL) in Birds?

Researchers from the Institute of Biology Leiden is investigating potential noise-induced hearing losses (NIHL) in birds that reside near airports.

In a recent study in the Journal of Animal Ecology, Wolfenden and colleagues (2019) found that birds near the airport sing at lower frequencies than other birds of the same species. The investigators suggest the altered song frequency may be due to NIHL at higher frequencies.

In addition, the birds in the noisier areas of the airport showed more aggressive responses to songs when compared to birds in a quiet control area, which may be related to noise-induced physiological stress or disturbed communication.

The researchers are concerned that this unusual aggression will impact reproductive efforts and could make the species more susceptible to injury and predators. Similar to humans, birds are affected by noise pollution, and the impact of extreme noise on birds should be considered in environmental impact assessments for airports.

Reference

Wolfenden AD, Slabbekoorn H, Kluk K, de Kort SR. (2018) Aircraft sound exposure leads to song frequency decline and elevated aggression in wild chiffchaffs. J Animal Ecology. October 25.