Midland Chorus Frog

Overview:

Scientific Name: Pseudacris triseriata

Size: 0.7 – 1.5” (adult size)

Status: Can be common to abundant locally, but many populations have recently declined, particularly in suburban and agricultural areas.

Habitat:

Prefer marshes, meadows, swales, and other open habitats. May occur in wet woods and wooded swamps. Found beneath logs, rocks, and leaf litter. Found in the Lower Peninsula.

Conservation:

Is quite tolerant of human activities with presence in many agricultural and suburban areas. Local declines are known but are poorly studied. Many of the shallow breeding sites are filled by surface runoff and are vulnerable to contamination by pesticides, fertilizers, and other pollutants which can affect the eggs and larvae. Currently is listed as a species of greatest conservation need in the state of Michigan.

Best Management:

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.

Adult Coloration:

Brown, reddish, or tan to grey or olive body color with a white or cream stripe along the upper with bordered by a dark brown stripe running from through the eye from the nose to the groin. Usually has three stripes that run down the back that may be broken up into spots. The belly is cream or white with occasional dark spots on the throat and chest.

Adult Characteristics:

The skin is slightly bumpy but is moist. The toes are slightly expanded into pads. Males are slightly smaller with a yellowish vocal sac that is apparent as a grey flap of skin. Call is a short, scratchy “cree–ee–ee–ee-eek” similar in sound to that of a comb being strummed with a fingernail.

Larvae Characteristics:

Tadpoles are rounded and grey or brown from above sometimes with a brassy mottling as they age. Tail fins are clear with dark speckling. The intestines are visible through the bronze belly. Maximum length prior to metamorphosis is 1.2”.

Species Confused With:

The Spring Peeper does not have the distinct white upper lip stripe and usually has an X-shaped mark on the back. Blanchard’s Cricket Frog has rougher skin and does not have a white lip line or dark stripes on the back. Small Wood Frogs have similar markings on the lip but their dorsolateral folds (raised ridges extending down each side of the back) differentiate themselves.