At a sprawling landfill near Madrid, hundreds of white storks dodge garbage trucks as they look for scraps of food among the mountains of multicoloured garbage bags.
The birds have traditionally flown from across Europe to African pastures for the winter and returned in the spring.
But the abundant food found in landfills combined with warmer weather are making growing numbers of storks skip this arduous journey and stay in Spain for the winter.
The landfill receives between 200 tonnes and 300 tonnes of food waste per day and the storks head immediately to the zones where there is fresh garbage.
The scene is repeated across Spain, with many storks opting to nest close to landfill sites where they live year-round.
The municipality of Pinto is considering covering its landfill site to prevent storks from swallowing plastic and other potentially harmful items.
Younger storks still have the instinct to migrate to Africa but they make the trip without their parents, said SEO Birdlife ornithologist Blas Molina.
While the easy availability of food at landfills is the main reasons storks have stopped migrating, it is also “probably due to tendency towards higher temperatures” caused by climate change, the NGO said in a recent report.
Adult storks are staying “a little bit further north” within the Iberian Peninsula whereas before they stopped off in the southeastern region of Extremadura and Andalusia in the south, said Molina.
The change in the stork’s migratory habits is a clear example of the “effects of human activity on biodiversity,” he added.