Researchers find Kirtland's Warblers behave differently than thought | Michigan Radio

Researchers find Kirtland's Warblers behave differently than thought

Aug 21, 2020

Kirtland's Warblers don't always stick around their original breeding grounds.
Credit USFWS Midwest

Every year about 93% of all the Kirtland’s Warblers in the world fly from the Bahamas to Michigan. The rare bird is making a comeback from the brink of extinction.

The Smithsonian Migratory Bird Center and the Georgetown Environment Initiative teamed up to go the Bahamas and put tiny radio trackers on the birds.

It was thought when they got to Michigan the birds paired up and nested, end of story.

“But it turns out that some of the birds actually move up to 75, 80 kilometers at a time during the breeding season when everybody else is on a nest,” said Nathan Cooper, a research ecologist at the Smithsonian Migratory Bird Center. He’s the lead author of a report on the research published in Current Biology. He’s also a Michigan native.

Cooper and his team think some birds fail in breeding and want to try again so they go somewhere else.

“And then there's also males that were not able to attract a female. And so they're moving long distances probably to try to find a female for that year, but also trying to figure out where should I come back and try again next year,” he said.

Cooper says this might be true of other songbirds which seem to stray from typical breeding grounds.

The Kirtland’s Warblers were down to 167 males in the late 1980’s. Today there are 2,300 males. They were removed from the Endangered Species List last fall.

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