Cope’s and Eastern Gray Treefrogs

Overview:

Scientific Name: Hyla chrysoscelis/versicolor

Size: 1.2 – 2.4” (adult size)

Status: Locally abundant throughout their native range

Habitat:

Found in deciduous or mixed forests, farm woodlots, swamps, old fields, and well-vegetated yards and suburban areas. Will inhabit areas where suitable breeding ponds are located near trees or shrubs.

Conservation:

Remain common throughout the Great Lakes basin even in agricultural and low-density residential developments provided there are suitable breeding ponds. The drainage or degradation of small ponds, marshes, and other wetlands can eliminate populations quickly. The introduction of game fish in formerly fishless ponds is a detriment to the species. Pesticide applications on trees and shrubs or near wetlands inhabited by treefrogs can be harmful but further research is needed on chemicals, formulations, and reductions in prey.

Best Management:

Fall pesticide applications when larvae have metamorphosed and begun hibernations is recommended. Consider the effects of altering or destroying vernal pools and other fish-free ponds. Do not impact the pool depression or core buffer area within 100 feet of the pools and aim to protect a wider buffer of 600 – 1000 feet around the pools. Try to maintain the forest canopy and any habitat corridors to other vernal pools and upland habitats, these landscape mosaics are important to the species. Crossing structures can help reduce the effects of habitat fragmentation by roadways. Wildlife barriers to prevent access to areas where injuries and fatalities can occur is recommended.

Adult Coloration:

Coloration is variable with individuals having the ability to change color within one or more hours. Body color is usually grey-white, brown, or pale brown. One or more dark blotches outlined in black may occur on the black. A dark stripe or band extends from the eye to the front leg. Often a white, squarish blotch occurs beneath each eye. The belly is white, and the inner thighs and groin is bright yellow or orange.

Adult Characteristics:

Skin is warty and moist with large adhesive pads on the toe tips. Males are slightly smaller than females with an apparent vocal sac that is grey, loose skin on the throat. The call of the two species is their main distinguishing characteristic. The Eastern Grey Treefrog (H. versicolor) has a loud, musical trill last ½ a second to 3 seconds while the Cope’s Grey Treefrog (H. chrysoscelis) hasna faster, harsher, more nasal trill.

Juvenile Characteristics:

Metamorphs are usually bright green without a lot of marking on the back.

Larvae Characteristics:

Tadpoles are greenish or yellowish on the back with gold flecks or streaks. The belly is whitish. Tail fins are relatively high arched and usually tinged red or orange with black spots on the edges.

Species Confused With:

These species are unlikely to be confused with others. Northern Spring Peepers are much smaller and lack the yellow inner thighs. The trill of an American Toad is somewhat similar but lasts considerably longer (6 – 30 seconds). The “warning” trill of the Spring Peeper is almost always preceded or followed by a few short “peeps.”