Monk parakeets from South America have pushed northward to the Chicago area, causing bird watchers to worry whether they will force out backyard birds.
Several birders will be observing the birds to see whether they get along with native species, information that may help officials determine whether the parakeets are pests or guests, the Chicago Tribune said.
"I think you can't ignore it anymore," Christopher Appelt, a St. Xavier University professor overseeing the study told the Tribune. "I think you have to find out what it means."
Observers note that the monk parakeet has a reputation for being an agricultural pest in South America. They are, said Doug Stolz, a Field Museum of Natural History ornithologist, "extremely messy eaters."
The parakeets, which adapt easily to their environment, build nests, mate and hang out as humans watch and record. Pockets of the species thrive in 14 states, including Illinois, New York, Colorado and Florida, the newspaper said.
In the early 1970s, the U.S. Fish and Wildlife Service captured almost half the feral monk parakeets in the United States at the time but populations rebounded.
Copyright 2007 by United Press International
Explore further: Teen elephant mothers die younger but have bigger families, study finds