Climate change shifts breeding time for finches

Wild house finches are breeding earlier in the season with a warming climate. ©Renee Grayson

Wild house finches (Haemorhous mexicanus) are changing the timing of their breeding season due to changes in climate, according to recent research. Researchers already knew that many birds were breeding as temperatures warmed earlier, but didn’t yet know if seed-eating birds were also shifting their breeding times. In the study, the research team gathered museum records of house finch nests in California from 1895 to 2007. They then looked at records of spring temperatures in the regions where the nests were found. For every degree Celsius increase in temperature, the team found, the birds were laying eggs about 4 ½ days earlier. This could be a problem for finches, which need to match their breeding time to seed availability. But it may be beneficial if they take advantage of the longer breeding seasons to make more nests and produce more offspring.

Read the study in Ibis, the International Journal of Avian Science.