The flight season of butterflies is responsive to temperature and could be altered by climate change, a Canadian study says.

Researchers found that butterflies possess a widespread temperature sensitivity, with flight season occurring an average of 2.4 days earlier per degree Celsius of temperature increase, said the study, published in journal Global Change Biology.

The discovery was made after the researchers combed through Canadian museum collections of more than 200 butterfly species and matched them with weather station data going back 130 years.

"With warmer temperatures butterflies emerge earlier in the year, and their active flight season occurs earlier," said Heather Kharouba, lead author of the paper.

"This could have several implications for butterflies. If they emerge too early, they could encounter frost and die. Or they might emerge before the food plants appear and starve."

Butterflies also provide an early warning signal for how other wildlife may respond to climate change, said the researchers. Endi