Green Frog, Cheboygan Co., Michigan

Last weekend I traveled north to the Straits of Mackinaw and it turned into a frog weekend. At Mill Creek State Park we found several Green Frogs (Rana clamitans melanota). Green Frogs are easily identified by their rounded eardrum (called a tympanum), a fold of skin (the dorsolateral fold) extending partway down the body, and a green or yellow upper lip. Females have tympanums that are the same size as their eyes and white throats. Males have tympanums that are noticeably larger than their eyes and yellow throats. The overall color of the species varies; Green Frogs can be yellow, brown, green or combinations of these colors. The morning temperature was cool (low 50s F) so the frogs were not too active and very difficult to see among the vegetation.

Leopard Frog, “Green” Form, Emmet Co., Michigan

Northern Leopard Frogs (Rana pipiens) proved to be common at Wilderness State Park and the population contained many color variations. As I reached the park after lunch, the frogs were active in the heat of the day. Leopard Frogs resemble Pickerel Frogs but the underside of the hindleg is white in Leopard Frogs and yellow or orange in Pickerel Frogs. Leopard Frogs have two rows of roundish, dark spots on their backs. These spots are sometimes banded in a lighter color. Leopard Frogs also often have a spot behind each eye.

Leopard Frog, “Brown” Form, Emmet Co., Michigan

I chased frogs for a few hours, getting many photos of empty sand or plain vegetation (and giving thanks that I was no longer shooting film!) but, finally, I obtained a few passable photographs.

On our way home we stopped at Diane’s Bog and found a Wood Frog (Rana sylvatica). This is a small frog—less than three inches long—with a dark mask, underlined in white, extending from the nose to the tympanum (remember the eardrum). It has a fold of skin partway down its side.

Wood Frog, Oscoda Co., Michigan

When I left home for the weekend I was not thinking about frogs. I have learned that the best way to travel is to just go and keep an open mind to the possibilities. You never know what you can find if you just look.