Storks give up migration, choose landfill diet instead

Storks are known as migratory birds. In Europe, they're supposed to fly south to Africa for the winter. But lately, they've been putting those trips on hold — because of junk food.  

According to a new study, several thousand white storks in Spain and Portugal are staying put over the winter and they're congregating where the food is abundant and delicious: garbage dumps. 

"The dumps are landfill sites where trucks come and deposit all the rubbish that comes from our houses," Aldina Franco tells As It Happens host Carol Off.  "They are relatively dirty places, smelly places, with rotten organic matter and lots of plastic and other rubbish."

Franco is a conservation ecologist and the co-author of the study. She explains that European white storks used to migrate to Africa during winter months but in recent decades, as the birds discovered the landfills, more and more they stay put living off the garbage diet.

"It's a constant and reliable food resource," Franco explains. "They grab everything they can really. We saw some eating even inedible things like computer parts or bits of plastic."

Franco says it's too early to know the long term health effects of the pathogens the birds are consuming. But surprisingly, the study shows the immediate consequences may be in the species favour.

"They created new colonies," Franco explains. "They manage to raise a larger number of chicks, so their offspring is bigger than the storks that still feed on natural areas."

Franco adds that with the European Union planning to shut down open air landfills by 2018, the sudden depletion of the newly established food source could pose another challenge for the species.

"What will happen is the storks, and other birds like seagulls, egrets, and kites, will no longer have access to this food resource," France explains. "But we are excited to see what will happen and whether some of these storks that are now residents will then change their strategy and become migrants."