Jan. 17 (UPI) -- As global warming disrupts the timing of seasonal changes, scientists are concerned the biological clocks of migratory birds and other animals will be thrown out of whack.
To determine whether such a phenomenon is already underway, scientists have been documenting the springtime vocalizations of songbirds in Northern California's Klamath Mountains and Southern Cascades.
Scientists used automated recorders to record the calls of songbirds between 2009 and 2011. The recorders were spread out across a 155,000-square-mile area. The recordings identified the calls of eight different species, as well as the timing of peak vocalization for each. Peak vocalization represents an uptick in mating activity.
The observations were conducted over too short a time period to draw strong conclusions about longterm climate impacts on bird behavior. The research -- published this week in the journal The Condor: Ornithological Applications -- served mostly as a proof of concept.
But scientists did find some evidence that the vocalization and mating patterns of long-distance migrators are more likely to be disrupted by climate change.
"Climate change is disrupting songbird populations, distributions, and breeding behaviors in our mountain ecosystems," Michael McGrann, a researcher at William Jessup University, said in a news release. "Mountains are particularly sensitive because temperature and precipitation interact in complex ways on mountains."
If migratory birds struggle to mate in the opportune time, they could find themselves raising young their young too early or too late relative to the peak productivity of their preferred sources of food, like berries and insects.
"Our technique should allow us to track shifts in elevation, changes in the state of the population, and changes in breeding behaviors in response to climate change over the next ten to twenty years," McGrann said.