Global environmental change and human-made pollution have changed the migration routes of birds, especially storks, according to a new study from the University of East Anglia (UAE).
An increasing number of storks no longer migrate from Europe to Africa for the winter, but instead many live in Spain and Portugal the whole year round - feeding on "junk food" from landfill sites, reported the university in a press statement. Addicted to junk food and making round-trips of almost 100 kilometers to get their fix, white storks are now residents, nesting and living near landfill sites all year round. The research team tracked 48 birds using GPS tracking devices which transmit their positions five times a day. "We found that the landfill sites enable year-round nest use, which is an entirely new behavior that has developed very recently. This strategy enables the resident birds to select the best nest sites and to start breeding earlier," said lead researcher Aldina Franco, from UEA's School of Environmental Sciences. Franco also said that the stork population in Portugal has increased 10 times over the last 20 years.
"These are exciting times to study animal migration. Several species, including the white stork, which used to be fully migratory in Europe, now have resident populations. We want to understand the causes and the mechanisms behind these changes in migratory behavior," Franco further said. Researchers fear that the closure of landfills, as stated in the EU Landfill Directives, may have a dramatic effect on their population.