Date: November 13, 2015
Source: Dartmouth College
Phenological mismatches, or a mistiming between creatures and the prey and plants they eat, is one of the biggest known impacts of climate change on ecological systems. But a Dartmouth-led study finds that one common migratory songbird has a natural flexibility in its breeding time that has helped stave off mismatches, at least for now.
The results suggest this flexibility provides a buffer against climate warming for the black-throated blue warbler in eastern North America and potentially for other migratory forest birds in temperate zones, but such resilience probably has limits.
The study appears in the journal Oikos. The research included scientists from Dartmouth College, Norwegian Institute of Nature Research, Smithsonian Conservation Biology Institute and Wellesley College.
"Understanding the effects of climate warming on ecological systems is critical for the conservation of forest bird species and their habitats," says lead author Nina Lany, who conducted the study as part of her doctoral degree at Dartmouth and is now a postdoctoral researcher at Michigan State University.
The researchers studied the causes and consequences of year-to-year variation over 25 years in the breeding time of the black-throated blue warbler in the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire. They compared its breeding time and success to the timing of spring leaf-out and the availability of the leaf-feeding caterpillars eaten by birds. The timing of spring leaf-out varies by as much as a month from year to year in hardwood forests of the northeastern United States. This variability poses a challenge to migratory birds that migrate from the tropics and then time their breeding to maximize reproductive success.