Crawfish Frog, Rana areolata
The Crawfish Frog (Rana areolata or Lithobates areolatus) is a medium-sized species of frog endemic to the prairies and grasslands of the central United States. Its name comes from the fact that it inhabits the burrows of crayfish for the majority of the year.
The crawfish frog grows from 2.2 to 3.0 inches long. It ranges from yellow to brown in coloration, with a white ventral surface. The numerous dark brown colored spots featured on its back each have a light-colored ring around it. It has a distinct skin fold on either side of its back, which is much more pronounced in males than females, and relatively small tympanum.
These frogs are found mostly in association with prairie or grassland habitat, though they will also utilize pastures and overgrown fields. They spend the majority of the year in association with a terrestrial crayfish burrow. This species spends a substantial amount of time active and above the ground even on hot summer days, but they never stray far from their burrow which serves as an important retreat from any predators, a vital source of water, an escape from grassland fires, and a means to get below the frost line during winter. Crawfish frogs feed opportunistically on insects and other small sized invertebrates that pass by their burrow.
These frogs breed following mild and rainy weather in mid-March throughout most of its range. During this time, the males seek out ephemeral ponds and wetlands that lack fish and begin calling. The low-frequency call may carry over a mile, attracting the females in from the surrounding area. Once the females arrive, amplexus occurs and the females deposit up to 7,000 eggs at a time in large and globular masses. The eggs hatch in around 12 days, and the tadpoles complete metamorphosis into frogs within three to four months. The newly metamorphed juvenile frogs must hurry to find a crayfish burrow to occupy to avoid predation. Crawfish frogs achieve sexual maturity at two to three years of age and may live up to seven years or more within the wild.
The frog can be found in former prairie regions from Indiana west to Kansas, south to Texas, and east to Mississippi, though it’s believed to be locally extirpated in many regions, and remaining populations are often localized and isolated.
The two subspecies of this frog are the Southern Crawfish Frog, R. a. areolata and the Northern Crawfish, Frog R. a. circulosa.
Image Caption: Rana areolata. Credit: Stanley Trauth/Wikipedia (CC BY-SA 2.5)