RUMFORD – After emerging from their cryogenic-like hibernation, wood frogs have one thing on their minds: sex.

And it doesn’t matter with who or what, because they can’t eat until they’ve mated.

This spring, the 2- to 2½-inch frogs that quack like black ducks have a serious dilemma.

“Club Amphibian,” their favorite vernal orgy pools, are still iced over in western, central and northern Maine, said Aram Calhoun.

Calhoun is a University of Maine associate professor of wetland ecology and a wetland scientist for Maine Audubon in Orono.

“There’s a little, little bit of open water around the edges, so the animals usually hang out around the edges, waiting to get in,” Calhoun said.

“Isn’t that something? That must be depressing for a cold-blooded animal. You get to the edge of the pool, and the whole bloody thing is frozen and they’re probably saying, ‘I told you it was too early to go.’ There will be a lot of salamander divorces this time of year,” she said.

To reproduce, wood frogs and salamanders must breed in water.

The annual mating ritual comes during that first warm spring rain that researchers call the “Big Night.”

That’s when frogs and salamanders move in massive numbers through the woods to participate in breeding frenzies.

Big Night’s already happened in southern Maine and is expected to happen on Wednesday in the Orono area where Calhoun monitors amphibians.

In western Maine, Big Night should arrive during the fourth week in April or with the first warm rain, Calhoun said.

Several squished frogs on a road at night is a Big Night indicator, Calhoun said.

Salamanders prefer to move when it’s wet, but wood frogs will move even if it’s dry. That’s because salamanders have many years to be successful with breeding; wood frogs, which are found as far north as the Arctic Circle, don’t.

“Wood frogs are explosive breeders, yet they only live 3 to 5 years, so they only have a couple of times, if that, to breed,” Calhoun said. “So, they’re very anxious. Much more than the salamanders, which live 15 to 20 years.”

Salamanders gather congress-style – they all get in the pool together – and do a little courtship dance, and no one gets hurt.

With wood frogs, it’s not good to be a female.

“It’s not uncommon for the females to drown, because she has three or four males on top of her,” Calhoun said.

Wood frogs are the only frogs she knows of that attempt to mate with non-frog species.

To illustrate just how crazy wood frog sex can be, Calhoun’s graduate student, Kevin J. Ryan, who is working on his study site in Canterbury, Conn., photographed a wood frog trying to mate with a salamander.

“We’ve had wood frogs mating with our data loggers,” Calhoun said. “The data loggers, they’re in little plastic containers and they’re mating with the containers. They don’t care. It’s just something to put your arms around. It’s been a long winter, you know?”

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