FALMOUTH (AP) — Maine Audubon is asking Mainers to volunteer to observe frogs and toads in their neighborhoods.

The group says the long, cold winter means Maine residents are just now starting to hear frogs peeping in the Portland area. Audubon anticipates frog activity will increase during the week of April 13. The group says the need for volunteers is especially critical now because frog and toad species make their mating calls for a period of only about two weeks.

Audubon wants volunteers to drive an assigned route three different times during the spring and stop at designated areas to observe the presence of nine species. Online training is available.

Audubon says it especially needs volunteers in northern, western and Downeast Maine.