The National Park Service is not known for pranks, but a lot of people accused it of tomfoolery after a park in Wisconsin shared a photo of rocks and swore there was something alive in it — or several somethings.
“Can you find it or them?” staff at Saint Croix National Scenic Riverway asked.
The only hint given on Facebook was that it may or may not be one or more frogs.
The challenge apparently drove some people a little crazy, and they began imagining things.
“I’m seeing maybe 2 possibly 3,” one person wrote.
“Is there one under the leaf at bottom center?” another asked.
Spoiler alert: The answer is one gray treefrog — a species of zombie frogs that are technically both dead and alive in cold months.
However, the frog was so tough to see, the park had to draw a red circle around it and repost the photo. Even then, it looked like a rock. (See below.)
The “chameleon-like” species is known to change color with changes in temperature, state experts say.
“That is some great camouflage or frog-ou-flage!” the park wrote. “When temperatures begin to fall, gray treefrogs, and other terrestrial frog species like spring peepers, chorus frogs and wood frogs will isolate themselves in leaf litter or under a log.”
The park, which is about 60 miles northeast of Minneapolis, is home to 11 species of frogs and toads. The gray treefrog is a species known for its ability to be technically dead in the winter, the park says.
“As their body temperature drops to freezing, their bodily fluids converts glycerol to glucose; a natural antifreeze that prevents ice crystals from forming in the tissues,” the park posted.
“They gradually stop breathing, their hearts stop and brain waves cease. To a certain degree, they are dead. Come spring, however, their bodies warm and they resume their lives.”