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Frogsicles. Poke through a leaf pile this weekend and you might find one.
Sure, it can’t compare to what happened last month during a frigid spell in Florida, when meteorologists warned residents to watch out for cold-stunned iguanas dropping from trees like coconuts.
But frozen frogs are still pretty weird.
So back to us.
Our frogs awakened a little early this year, nudged by a relatively warm winter and the recent wet spell.
But when the mercury nosedives — like the below-freezing nights forecast for Friday and Saturday — and frogs have already rolled out of bed, some can manage a feat that would be curtains for most creatures.
Some frog species, including several found in our area, can freeze — we’re talking ice inside their bodies — then thaw and go about their business just fine.
“Frogs are a lot more durable than we are when it comes to temperatures,” said Dennis McNamara, lead reptile keeper at the Virginia Zoo in Norfolk.
Mind you, a frozen frog looks plenty dead. And some are indeed goners, since not all possess the freeze-then-resurrect trick. Those that don’t can only duck for cover, burrowing back into the holes, creeks, crevices, mulch beds or leaf litter where they usually wait out winter, napping in a sluggish state called brumation.
That’s the cold-blooded animal’s version of hibernation. Organs and movements slow but can temporarily rev during windows of warmth.
Barometric pressure can also trigger a stir. Storms bring rain, a signal for frogs that a time of plenty may be at hand and they’d better get to breeding.
“Rains bring more food,” McNamara said, “and that’s the best time to have babies.”
This weekend’s cold snap put a hitch in their early plans.
Frogs come in 4,800 of species, but only five found in North America are in the freeze-tolerant family, which also includes a handful of insect species, reptiles and other amphibians.
The frogs start their process — which still isn’t completely understood — as soon as thermometers hit 32°F and ice crystals touch their skin. Glycogen in their bodies converts to glucose, which helps keep cells from dehydrating. As the chill deepens, organs stop functioning and as much as 70% of the water in their bodies can become frozen — a condition they can survive for months.
But as resilient as they are, frogs and other amphibians are considered indicator species — a canary in the coal mine, so to speak, for pollution, climate change, pesticides. They’ve been around for more than 200 million years, enduring on every continent except Antarctica, but more than 120 types of amphibians have gone extinct recently, according to the zoo.
Frog populations can be hard to monitor.
“They hide, they come out at night,” McNamara said. “The best way to find them is with your ears.”
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The zoo sponsors a chapter of FrogWatch USA, a national Citizen Science program that teaches volunteers to identify species by their calls, record the when and where and take a guess at how many singers are in the symphony.
“We listen for 21 species in our area,” McNamara said. “Each type makes a different sound and they all have a couple of different calls depending on what it’s for. Most of the noises you hear outside at night aren’t insects or birds. Ninety percent of it is frogs and toads.”
FrogWatch training consists of a free, four-hour class. The zoo has already held two this year and will post upcoming classes on its Facebook page.
The aquarium in Virginia Beach, which also hosts a chapter, has a class scheduled for March 8.
In the meantime, if you come across a stiff, lifeless looking frog this weekend, just leave it alone.
Given the forecast — temperatures rebounding into the 50s by Sunday — there’s a good chance it’ll be hopping again soon.
Joanne Kimberlin, 757-446-2338, joanne.kimberlin@pilotonline.com