Boreal Chorus Frog
Boreal Chorus Frog
Pseudacris maculata
(Hylidae)
Global Rank:
G5
State Rank:
S4
Agency Status
USFWS:
USFS:
none
BLM:
none
General Description
Adults have a tiny, almost unnoticeable toe pads; a dark line extends from the snout through the eye to the groin. Basic coloration varies, with background color green, brown, gray, or reddish. Typically three to five dark longitudinal stripes are present on the head and back; in some individuals the stripes may be broken into spots. Adult body length is .75 to 1.5 inches. Eggs and Tadpoles: Eggs are laid in clusters of 20 to 100; clusters are usually less than 1 inch across and attached to submerged vegetation. Tadpoles are brown/bronze with eyes located on the sides of the head.
Diagnostic Characteristics
Pacific chorus frogs have obvious toe pads and an eye stripe ending at the shoulder.
Migration
nonmigratory.
Habitat
Western chorus frogs are regularly found in the water only during the breeding period in spring. They announce their presence this time of year by calling frequently at night and sporadically during the day. Following breeding, they move into adjacent uplands and are rarely seen. In eastern Montana, they breed in temporary ponds and small lakes surrounded by prairie (or occasionally open forest) habitats. Eggs hatch in about 2 weeks and tadpoles take 8 weeks to metamorphose (FWP). Inhabits marshes, ponds, small lakes in all life zones incl. lower alpine (Baxter and Stone 1980). When not breeding, generally found in damp grassy/marshy areas or damp forests near water, but has been found up to 0.5km from water (Nussbaum et al. 1983, Hammerson 1982).
Food Habits
Ants, spiders, flies, beetles, aphids and other insects (Nussbaum et al. 1983).
Ecology
Most common amphibian noted in NC MT. In high mtn males may not breed until 2nd yr, fems @ 3rd year. Survival to adulthood may be only ca. 1% in mtn pops. (Hammerson 1982).
Reproductive Characteristics
Breed late Mar-early Jun in WY (Hammerson 1982). Noted singing in early Apr in SW ID and as late as early Jul (Nussbaum et al. 1983). Eggs hatch in 10-14 days; metamorph. in ca. 2 mos. (Nussbaum et al. 1983). Metamorph. obs. late Jul-Aug in NC MT (Mosimann and Rabb 1952).
Citations & Sources
- Baxter, G. T. and M. D. Stone. 1980. Amphibians and reptiles of Wyoming. WY Game and Fish Dept. 137 pp.
- Hammerson, G. A. 1982. Amphibians and reptiles in Colorado. Colorado Division of Wildlife, Denver. vii + 131 pp.
- Maxell, B., Werner K.J., Hendricks, and P., Flath, D., 2003. Herpetology in Montana. Society for Northwestern Vertebrate Biology
- Mosimann, J. E. and G. B. Rabb. 1952. The herpetology of Tiber Reservoir Area, Montana. Copeia 1952:23-27.
- NatureServe Explorer: An online encyclopedia of life [web application]. 2002. Version 1.6 . Arlington, Virginia, USA: NatureServe. Available: http://www.natureserve.org/explorer. (Accessed: March 20, 2003 ).
- Nussbaum, R. A., E. D. Brodie, Jr. and R. M. Storm. 1983. Amphibians and reptiles of the Pacific Northwest. Univ. Press of Idaho. 332 pp.
- Reichel, J. D. and D. Flath. 1995. Identification of Montana's amphibians and reptiles. Montana Outdoors 26(3):15-34.
