We spent many hours during the last spring migration at the crest of Washington D.C.’s Rock Creek Park, hanging out with some of the area’s most experienced birders waiting to see what species would appear next.
When the mornings were slow, the conversation sometimes turned to how unpredictable the migration has become: Some days would be as quiet as July, and others suddenly filled with a flurry of unexpected migrants flying through.
For years, birders around the country have watched the evidence gather that the bird world has been disrupted.
But this fall, three scientific reports in succession, including a major study released today, have fundamentally altered the picture of what’s happening. Modern technologies are enabling a new level of research about birds, migration, breeding and populations with a precision not possible just a few years ago.
Today’s study is the first to document how birds are starting their spring migration journeys a great deal earlier to keep up with climate change. And while migratory birds are trying to adjust, the research based on 24 years of weather radar data suggests that the intricate balance of when plants flower, insects arrive and birds start breeding are falling out of sync for some of these species.
“How bird populations respond in an era of such rapid and extreme changes in climate has been a black box,” said Andrew Farnsworth, a co-author of the migration study and researcher at the Cornell Lab of Ornithology. “Capturing scales and magnitudes of migration change over time has been impossible until recently.”