Rare North American Frog Species

North America seems to be a haven for frogs and toads. There are more than a hundred species in North America and not a single state or country on the continent is without one or more species. Frogs are abundant in North America. However, there are some species of frogs on the continent that are rare and sometimes elusive. Habitat tends to be the cause of rarity for all of the following frog species. For some it is habitat loss that is causing a problem with the population. Others just have a naturally small range. Either way, the effect is the same. These frogs are very difficult to find.

Rare North American Frogs: Florida Bog Frog

The Florida Bog Frog can only be found in a very small portion in the Midwestern area of Florida’s panhandle. In that area, they can only be found in the drainages of the East Bay River, the Titi Creek and the Lower Yellow River. They are not considered endangered, however, their very limited range makes them very vulnerable to habitat destruction or alteration.

Florida Bog Frogs are green or murky green in color. They may have darker greenish spots on their backs and/or light yellowish-green spots on their sides. They have very little webbing on their rear feet. They grow to be between 1-3/8 inches and 1-15/16 inches in length.

As is the case with most frog species, Florida Bog Frogs are much easier to find during the mating season, when the males are emitting their mating calls. This happens between April and August, sometimes as late as September.

Rare North American Frogs: Pine Barrens Treefrog

The Pine Barrens Treefrog can be found in New Jersey, the far western Florida panhandle, a very small portion of southern Alabama, and small portions of both North and South Carolina. They can be found in boggy areas where they breed in the spring and summer. Males are often more active in their mating calls after it rains.

Pine Barrens Treefrogs are medium green with a white and brown stripe from their snout all the way down their sides. The stripe may be speckled yellow near the frog’s joints. They grow to be between 1-1/8 inches and 2 inches in length.

Rare North American Frogs: Relict Leopard Frog

Relict Leopard Frogs are only found in a very small area in southeastern Nevada into northwestern Arizona. Their population has declined and their range has decreased in size due to invasive species and habitat changes.

Relict Leopard Tree Frogs are light brown to dark greenish-black in color. They often have darker markings all over. They may grow to be between 1-3/4 inches and 3-1/2 inches in length. They breed between February and April and again in November. However, their calls are very difficult to hear because they are often made underwater.

With the right habitat conservation efforts and/or captive breeding and release programs, not only can we ensure that these rare frog species will survive, but we may also be able to increase their numbers. Some of these frog species are already receiving the help they need. Others are not in dire need of any assistance, but habitat conservation should always be kept in mind.

Source

Elliott, Lang & Gerhardt, Carl & Davidson, Carlos, The Frogs and Toads of North America Houghton Mifflin Harcourt, 2009 p. 228-229, 292-293, 204-205, 52-55

Green Treefrogs: Bright and Beautiful Denizens of North America

Green Treefrog
Courtesy of Clinton & Charles Robertson

There are currently more than one hundred species of frogs and toads in North America, among them is the very pretty Green Treefrog. These frogs are also known as cowbell frogs or rain frogs. The reason for the former is that their calls often sound like bells. The reason for the latter is that they have a habit of becoming noisy after it rains (during the active season).

Green Treefrogs are light green in color and the surface of their skin is very smooth. They may have white stripes with black borders running down their sides and the sides of their snouts. These frogs may also have yellow spots with black borders on their backs. They can grow to be between 1-1/4 and 2-1/2 inches in length as adults. Green Treefrogs are found mainly along the southeastern and Gulf coasts of the U.S. Their range goes north as far as Illinois.

Like many other frog species, Green Treefrogs are most noticeable when they are mating. The males of the species will congregate in specific breeding sites and start emitting an ‘advertising’ call in an attempt to attract mates. They are not very territorial. However, if another calling male gets too close to them at this time, they will emit a ‘warning’ call. Once a female chooses a male to mate with, she will often nudge him to get his attention. At this point, the male will clasp the female in what is called axillary amplexus. In other words, he will mount her and grip her from behind her forelimbs. He then fertilizes her eggs. If an unwitting male should attempt to mount another male or an unwilling female, the offended Green Treefrog will emit a ‘release’ call.

These frogs most often lay their eggs in lakes, ponds, swamps or standing water after a heavy rain. After the Green Treefrogs eggs hatch, it will take the tiny tadpoles a couple of weeks to a month to become frogs. During the tadpole stage, it will live off of aquatic plant life. Once the Green Treefrog reaches adulthood, it will live off of insects.

Green Treefrogs, and most other frogs, are more active at night than they are during the hotter daytime hours. They typically spend their days in burrows or hiding places that contain moisture. This is so that the frog’s skin will not dry out in the heat. However, they will also become inactive in cold weather, because they are cold-blooded. So, the best time to find a Green Treefrog is during mating season, which is usually from around March to around August. All you need to do is follow the sound of their mating calls.

Source

Elliot, Lang, Gerhardt, Carl & Davidson, Carlos, The Frogs and Toads of North America, p. 44-47