Galapagos birds show “road rage” due to noise

A new study found birds in the Galapagos Islands changing their behavior due to traffic noise.

Published in the journal Animal Bee Butte and led by experts from Anglialaskin University (ARU) and the Conrad Lorentz Research Centre at the University of Vienna, the study investigated the effects of vehicle noise pollution on the Yellow Wargler (Setofer Gapetia Aureola) of the Galapagos, a Sombard Wide Sped at Archipelago.

Located more than 500 miles off the Ecuadorian coast, the Galapagos Islands are considered a natural living laboratory due to the numerous unique endemic species. The yellow warbler of the Galapagos is genetically distinct from other yellow warbler found in the Americas and is classified as a subspecies.

A visit to the Galapagos Islands in 1835 encouraged Charles Darwin to develop the theory of evolution through natural selection. However, in recent decades, the population has increased significantly. In addition to the increase in tourism, the permanent population is growing by more than 6% per year, leading to more vehicles on the island’s roads.

The new study involved traffic noise recorded at 38 locations where yellow warblers of the Galapagos live on Floana and Santa Cruz Islands, where researchers who play bird songs from intruders and simulate intruders.

Researchers then measured songs that are usually used to drive out intruders, approach speakers closely, and measure physical and aggressive behavior, such as repeat flights.

During the trial with traffic noise, researchers showed that yellow warbler in the Galapagos, living on roadside territory, showed increased aggression, while those living away from the road showed reduced aggression compared to noiseless testing.

Importantly, the effect of living on roadside territory existed even on Floreana Island, with only about 10 vehicles on the island, suggesting that even a minimal experience of traffic affects the response to noise.

Additionally, the yellow warbler of the Galapagos in Santa Cruz, a more populous island, increased the duration of the song when faced with traffic noise. These findings support the idea that song characteristics can be adapted and adjusted by long-term choices based on noise experiences or previous noise experiences of individual birds.

Finally, birds helped increase the minimum frequency of songs during noise experiments, even when the territory is close to the road, and reduce the overlap of songs with low frequency traffic noise.

Co-author Dr. Caglar Akcay, senior lecturer in Behavioral Ecology at Anglia Ruskin University (ARU), said, “Birds use songs as positive signals during territorial defense. However, it is a good response for external noise such as traffic to effectively interfere with this communication channel and increase physical attacks.

“Our results show that changes in the aggressive response of yellow warblers occurred primarily near roads. Birds occupying roadside territory on both islands may have learned that by having regular experience with traffic noise, they increase physical attacks when territorial invasions involve traffic noise.

“We also found evidence that birds are trying to deal with noise by adjusting their songs. Yellow warblers in all habitats increase the minimum frequency of songs so that they can be heard above traffic noise.

“Our research shows the importance of considering behavioral plasticity in conservation efforts and developing strategies to mitigate the impact of noise pollution on wildlife. It also highlights the impact of human activity on wildlife behavior, even in relatively remote locations such as the Galapagos Islands.”