Pandemonium in a Pond

VIDEO: Forty-two seconds of Wood Frog reproduction

NOW THAT WINTER has relented here in the northeastern U.S., we’re in our brief season of amphibian mating. No, not much courtship going on here among Wood Frogs (Lithobates sylvaticus). It’s mayhem. Biologists call it “explosive breeding.”

When the earth thaws, Wood Frogs (and other amphibians) emerge from their overwintering sites in muck or leaf litter and make their way to water for binge breeding. Males often outnumber females at these sites, which means, well … those males can be combative and “clingy.”

Male Wood Frogs fertilize eggs as females lay them in water. So this scene above is about “positioning.” The male who can best latch on to a female’s back (a maneuver called “dorsal amplexus”) is more likely to fertilize her eggs. So desperate are the males that they’ll grab just about anything that moves or might resemble a female, including salamanders or your submerged fingers.

In the video, you can barely make out the female — larger than the males, fawn brown in color, and facing the camera — underwater and besieged by about five males in the scrum. Typically, once the female finishes laying her eggs, the males relent and swim away (and seek other females). She’s sometimes left dazed or appearing comatose. Females sometimes die in these encounters.

So if you’ve ever needed evidence that females bear disproportionately the burdens of reproduction, there it is above — 42 seconds of pandemonium. After watching this round of amplexus with me at a local pond, my partner Ruth said: “Note to self: Try not to be reincarnated as a female Wood Frog.”

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Natural Selections — April 19, in Montpelier, Vermont

If you happen to be around Montpelier Friday evening, meet me and our ensemble for Natural Selections — an evening of poetry, prose, and music. A Poem City event, coinciding with National Poetry Month, our poets are Scudder Parker and Marjorie Ryerson. D. Davis (guitar) and Ruth Einstein (violinist and female Wood Frog sympathizer) will make music. And I’ll be reading two new short essays (coming to Chasing Nature) and showing a few photos. Natural Selections is a fundraiser for North Branch Nature Center, a little preserve with a big mission connecting people to the natural world.

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Wood Frogs in a more “civil” amplexus embrace beside a wetland. / © Bryan Pfeiffer