Rising temperatures are bringing earlier migration patterns, according to a new study out of UNC Chapel Hill. Allen Hurlbert and Zhongfei Liang collected data using ebird–a citizen science program database containing 10 years’ worth of observations from amateur birdwatchers–which now includes over 48 million bird observations from about 35,000 contributors. By considering 18 species at various locations during migration, they concluded that on average, each reached various stopping points 0.8 days earlier per degree Celsius of temperature increase.
That may not sound like much, but as Hurlbert explains:
“Timing of bird migration is something critical for the overall health of bird species. They have to time it right so they can balance arriving on breeding grounds after there’s no longer a risk of severe winter conditions. If they get it wrong, they may die or may not produce as many young. A change in migration could begin to contribute to population decline, putting many species at risk for extinction.”
It’s an interesting analysis highlighting how little we know about the impacts of climate change. There are observable direct effects on behavior and survival, but it’s far more challenging to measure species interactions within the larger system.
Read the full article in PLoS ONE.