From The New York Times
Birds are migrating earlier and earlier each year, and scientists have long suspected that climate change is responsible. A new study by researchers at the University of East Anglia in England shows that individual birds migrate like clockwork, but nesting and hatching are happening earlier as a result of warmer temperatures, and this appears to be linked to the advancing of overall migration patterns.
Fat Finch — Backyard Birds, Birding & Blogging 