A new study published in the journal PLoS ONE indicates that some songbirds are not altering their migration patterns to accommodate changing temperatures. As explained in this CBC News article, researchers tracked purple martins for several years and found that the birds did not leave their southern wintering grounds earlier even if the temperature was noticeably warmer. This could have an impact on what the birds are able to eat once they arrive at their destination, as insect populations are peaking earlier than the birds' arrival.
