Galápagos Islands – A new study reveals that birds in the Galápagos Islands are becoming more aggressive due to traffic noise. The research links this behavior to how close the birds live to roads.

The study, published in Animal Behaviour, was conducted by experts from Anglia Ruskin University and the University of Vienna’s Konrad Lorenz Research Centre. It focused on Galápagos yellow warblers, a songbird unique to the islands.

Located over 500 miles off Ecuador’s coast, the Galápagos Islands are known for their rare species. The yellow warbler here is a distinct subspecies, different from those in the Americas.

Charles Darwin’s 1835 visit to the islands sparked his theory of evolution. Today, human population growth and tourism have surged, with over 6% annual increases, bringing more vehicles to the roads.

Researchers tested the birds by playing songs and traffic noise at 38 sites on Floreana and Santa Cruz islands. They observed the warblers’ songs and physical reactions, like flying at the speaker.

Birds near roads showed more aggression when traffic noise played, while those farther away were less aggressive. Even on Floreana, with just 10 vehicles, the effect was noticeable.

On Santa Cruz, a busier island, warblers sang longer during noise tests. This suggests they adapt their songs based on past noise exposure.

All warblers raised their song’s minimum frequency during the experiments. This helps their calls stand out against low-frequency traffic sounds.

Dr. Caglar Akcay from Anglia Ruskin University explained that birds use songs to defend territory. When noise blocks this, they turn to physical aggression instead.

He noted that roadside birds likely learned to ramp up aggression during noisy intrusions. Adjusting song frequency also helps them cope with the noise.

The study stresses the need to address noise pollution in conservation. It shows how human activity affects wildlife, even in remote places like the Galápagos.

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