Storks now rely on landfill sites for food, especially during the non-breeding season when other food sources are more scarce,” said Aldina Franco, the study’s lead researcher, in a press release. “This has facilitated the establishment of resident populations.
Franco and her team followed 48 white storks’ movements between nesting and feeding areas to observe just how much they actually enjoyed the landfill life.
“We found that the landfill sites enable year-round nest use, which is an entirely new behavior that has developed very recently,” said Franco. “This strategy enables the resident birds to select the best nest sites and to start breeding earlier.”
“Having a nest close to a guaranteed food supply also means that the storks are less inclined to leave for the winter,” Franco added. “They instead spend their non-breeding season defending their highly desirable nest locations.”
Portugal in particular is in the midst of a booming stork population.
“Portugal’s stork population has grown 10-fold over the last 20 years,” Franco said. “The country is now home to around 14,000 wintering birds, and numbers continue to grow.”
While this may seem to be positive news, as the storks have found a permanent nesting site, and a safe place to raise their young. Trouble may be on the horizon though, in the form of imminent directives from the European Union.
“Rubbish dumps sites in Portugal are scheduled to be gradually replaced by new facilities where food waste is handled under cover,” said Franco. “This will cause a problem for the storks as they will have to find an alternative winter food supply. It may well impact on their distribution, breeding location, chick fledging success and migratory decisions.”