Hundreds of thousands of migratory birds have been found dead in New Mexico - CNN
https://www.cnn.com/2020/09/14/us/new-m ... index.html
Dead migratory birds -- which include species such as warblers, bluebirds, sparrows, blackbirds, the western wood pewee and flycatchers -- are also being found in Colorado, Texas and Mexico.
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Possible reasons
One of the factors biologists believe may have contributed to the deaths of the birds is the wildfires burning in California and other Western states, which may have forced the birds into early migration before they were ready.