Washington: A recent study has revealed that crows living in urban areas might be having higher blood cholesterol levels than those in rural areas. The study was published in the journal ‘The Condor: Ornithological Applications’. The food that humans throw away, such as discarded cheeseburgers, might be responsible for the difference.
Researchers carrying out the study sampled the blood cholesterol levels of 140 crow nestlings along an urban-to-rural gradient in California. They found that the more urban the environment, the higher was the blood cholesterol of the birds.
To directly test the effects of human food, the researchers also provided nestlings in a rural New York population with a regular supply of McDonald’s cheeseburgers and compared their blood cholesterol levels with those of nearby crows who had to fend for themselves. The crows who were fed cheeseburgers ended up with higher cholesterol levels than their neighbors, similar to those of the urban crows in California.
“Wild birds haven’t evolved to eat processed food, and it might have negative consequences that we didn’t measure, or that will only show up over longer periods of time,” said Andrea Townsend of Hamilton College, one of the co-authors.
“Some of the foods that humans give to wild animals, and living in an urban environment in general, might not be good for their health,” she added.