The northern leopard frog is perhaps most recognizable as the formaldehyde-soaked specimen in the high school lab tray.
Source: MrLundScience
Population decrease
Once the most common and abundant frog in North America, leopard frogs are widely collected not only for dissection but also for the food industry (frog legs).
However, large declines that began in the early 1970s, particularly in Canada and the western United States, have greatly reduced their numbers. Scientists have yet to determine the cause of the drop, but it is likely a combination of ecological factors: pollution, deforestation and water acidity.
Color and size
Northern leopard frogs are so named because of the irregularly shaped patches of black spots that adorn their backs and legs. They are greenish-brown in color with a pearly white underside and light ridges on the sides of the back. They are considered medium sized, reaching 3 to 5 inches in length, from nose to rump. Females are slightly larger than males.
Range and Habitat
Their range is most of northern North America, except on the Pacific Coast. They usually live near ponds and marshes, but will often also venture into well-covered grasslands, giving them the other common name meadow frog.
Diet
Leopard frogs will eat anything they can put in their mouths. They sit still and wait for their prey to arrive, then pounce with their powerful legs. They eat beetles, ants, flies, worms, smaller frogs, including their own kind, even birds and carnivorous snakes.