Galapagos birds show ‘anger on the road’ because of noise

A new study revealed that birds on the islands of Galápagos change their behavior due to traffic noise, with those often exposed to vehicles showing increased levels of aggression.

Published in the magazine Animal behavior And led by experts from Anglia Russian (ARU) and the Konrad Lorenz Research Center at the University of Vienna, the research examined the impact of the noise of vehicles on Galápagos Yellow Warblers (Setophaga Petechia Auola), songs that spread on the archipelago.

Galápagos Islands, located over 500 miles from the Ecuador coast, are considered a natural living laboratory because of a large number of unique, endemic species. Galápagos yellow turbler It is genetically different from other yellow warriors found in America and is classified as subspecies.

Visit to the islands of Galápagos 1835. He helped encourage Charles Darwin to develop the theory of evolution by Natural choice. However, in recent decades, they have recorded a significant growth of the human population. With the increase in tourism, the population is constantly increasing by over 6% annually, leading to several vehicles on the island roads.

A new study included researchers playing bird songs Of the speakers, a simulating intruder, followed by a traffic noise on 38 locations inhabited by Yarblers Galápagos on the islands of Florean and Santa Cruz – 20 seats were within 50 meters from the nearest road, and 18 were more than 100 meters away.

The researchers then measured the song, usually used to remove the intruders and physical, aggressive behaviors, such as carefully approaching the speaker and performing repeated flights over it.

During a traffic noise trial, researchers have found that Galápagos Yellow Warblers who live in road territories have shown increased aggression, but those who live away from the roads have shown reduced aggression over noise without noise.

It is important that the effect of life in the road territory was even present on the island of Florean, and there are about 10 vehicles on the island, suggesting that even the minimum traffic experience affects the noise answers.

In addition, Galápagos Yellow Warblers on the populated island of Santa Cruz increased the duration of their song when confronted with traffic noise. These findings support the idea that a long -term selection based on experience with noise or the previous experience of an individual noise enables to adjust and adjust the features of their songs.

Finally, the birds increased the minimum frequencies of their songs during experiments with noise, regardless of the proximity of their territory to the road, helping to reduce any overlap of their songs with low -frequency traffic noise.

Co -author Dr. Caglar Akcay, a senior lecturer in the ecology of behavior at Anglia Russian (ARU), said: “Birds use a song during territorial defense as an aggressive signal. However, if external noise such as traffic is disturbed by signaling, effectively blocking this communication channel, increasing physical aggression.

“Our results show that a change in aggressive responses in yellow warriors occurred mainly near roads. Birds occupying the roads on the road on both islands, and therefore regular traffic noise experience, may have learned to increase physical aggression when territorial intrusion was accompanied by traffic noise.

“We have also found some evidence of birds trying to deal with the noise by adjusting their song, and the yellow warriors in all habitats increase the minimum frequency of their songs to help them be heard above the traffic noise.

“Our study shows the importance of considering the plasticity of behavior in Efforts to preserve and developing strategies to mitigate the effects of pollution of the noise on wildlife. It also emphasizes the significant impact of human activities on wildlife behavior, even in relatively distant places such as the islands of Galápagos. “