Leo the northern leopard frog — named after conservationist Aldo Leopold — is always a hit with kids when he comes out during programs.
That is often because he makes the programs more exciting when he escapes from the grasp of the naturalist with his squirmy, slippery body.
But visitors also love to see his long legs, his ability to jump high, his interesting sounds.
Northern leopard frogs are quite interesting creatures, from their metamorphosis to their ability to freeze and thaw. Let’s take a look at some interesting facts about northern leopard frogs.
Frogs march along.
A group of frogs is called an army.
Females are prolific egg layers.
Northern leopard frogs breed between late April and early June, with each female mating only once. She will then lay a single egg mass including thousands of eggs — which a male fertilizes as the eggs leave her body — and then leaves the pond where the eggs are.
Adults don’t always live near water.
After breeding season, some northern leopard frogs will move away from ponds and wetlands to live in meadows or grasslands. They absorb water from dewy plants during this time. In the winter, they travel back to their “home” pond.
Some frogs don’t have spots.
The Burnsi color morph of a leopard frog is a genetic variation that is brownish-green but lacks spots.
They taste good.
American toads are covered in red and yellow wart-looking spots that actually contain glands that secrete poison. Don’t worry, it won’t hurt you if you touch them. The poisonous milky fluid makes them taste bad to predators, and it is harmful to predators when swallowed or if it gets in their eyes.
Leopard frogs do not have the same secretions as toads, or as pickerel frogs. Instead, northern leopard frogs leap into the water or erratically hop to escape predators. And they have a lot of predators — fish, herons, snakes, hawks, raccoons, foxes, otters, turtles and more.
Frogs freeze in the winter and thaw in spring.
Northern leopard frogs are native to northwest Iowa and are aquatic creatures, meaning they live in the water. Like American bullfrogs, which are not native to northern Iowa, northern leopard frogs will hibernate underwater.
They will lie on top of the mud at the bottom of a body of water or partially bury themselves. They will then freeze and thaw right along with their hibernacula — the place where they hibernate.
As the winter comes on and the area around the frog’s hibernacula freezes, ice crystals will also form in the frog’s body cavity, bladder and under its skin. The high amount of glucose — a type of sugar — in the frog’s vital organs, such as its heart, will prevent it from freezing completely.