The white stork seems to like the taste of garbage.
Birds in southern Europe are forgoing their annual migration in favor of spending their winters picking through the landfills of Spain and Portugal.
The white stork, scientifically known as Ciconia ciconia, used to be a totally migratory species. They are found across Europe and Central Asia in the warmer months and typically travel to Africa for winter.
However, over time these migratory birds have begun to settle near landfills, feasting on the abundant "junk food" found there, according to a study published Wednesday in the journal Movement Ecology.
A group of researchers at the University of East Anglia in the United Kingdom have been studying these storks, and say while some birds are continuing their migratory ways in winter, others are instead hanging around all year in the dumps of southern Europe.
The team attached GPS trackers to several birds to track their movements over the course of a year. They found some birds living year-round at the landfills, and discovered that even migratory birds are traveling farther to get to the landfills than previously thought.
Those who are staying year-round have an advantage in picking a spot to nest and they are breeding earlier in the following year.
"Having a nest close to a guaranteed food supply also means that the storks are less inclined to leave for the winter," said study researcher Aldina Franco in a press release. "They instead spend their non-breeding season defending their highly desirable nest locations."
Garbage makes up close to 70 percent of the food landfill storks are eating year-round, and the number of storks choosing to winter at the landfills has increased dramatically over the last decades. In 1995, there were just more than 1,000 storks overwintering at landfills in Portugal. By 2008, the number grew to more than 10,000, and by 2014, there were somewhere around 14,000, according to the study.
It is a considerable change in the animal's behavior, and is another example of the effect humans have on the behavior of other species.
Other scientists have previously noticed this changing behavior in the birds. Another paper published this past January also suggested storks living near dumps or areas with high human populations are shifting their migration patterns.
Of course, the storks' "junk food" supply may soon begin to disappear. Under the EU Landfill Directive, European countries plan this year to convert open-air landfills to closed waste-processing facilities the storks won't be able to access. How well the birds would be able to adjust to such a rapid change is unclear.