Field Guide Field Journal Blanchard's Cricket Frog

Field Guide Field Journal Blanchard's Cricket Frog

Field Guide Frogs and Toads of the Washington, D.C. Area Field Journal Name: Date: Blanchard's cricket frog Location: Acris crepitans Baird, 1854 Weather: Time of Day: Observations / Data / Activity Overview General Description Acris crepitans is 1.6-3.5 cm long and has a blunt, pointed head with an occasional triangular marking. Its back and legs are covered with various dark markings. It has a middorsal bright green or brown stripe and the rear of its thigh has a distinct ragged dark stripe. A white bar extends from its eye to its foreleg. The body is slim-waisted and small while the skin is granular and warty. Hind toes are extensively webbed and toe pads are poorly developed (Stebbins 2003). Acris crepitans paludicola and Acris crepitans blanchardi are recognized as subspecies. A. c. paludicola has smooth skin with a pinkish patterned coloration. The throat Write down questions that you have for further exploration. remains pink, even for males during breeding season. A. c. blanchardi by comparison is wartier, bulkier, and heavier with a light brown or gray uniform coloration (Conant and Collins 1991). Males have more ventral spotting than females (Stebbins 2003). Distribution Unlike most small frogs in its range, A. c. crepitans does not leave the vicinity of water in its adult stage. It is found at the edge of ponds and slow-moving streams, tending to avoid wooded areas and dense vegetation (Hulse McCoy and Censky 2001). A. c. blanchardi is found in Michigan, Ohio, Nebraska, eastern Colorado, and most of Texas. A few have been spotted in Minnesota and New Mexico as well. A. c. paludicola is found in marshes ranging from southwestern Louisiana to southeastern Texas (Conant and Collins 1991). Physical Description Morphology Acris crepitans is a small (0.75 to 1.5 inches), slim-waisted frog with slender webbed toes and a triangle mark on the head. Dorsal coloration can be gray, light brown with dark bands on legs. There is a white bar from eye to base of foreleg. The skin is bumpy. Males have a single vocal pouch. Acris crepitans is a non-climbing Page 1 member of tree frog family (Barket 1964, Stebbins 1966). It may be confused with the Striped Chorus Frog which has a whitish stripe along upper lip and length-wise brownish stripe on sides and back, toes slightly webbed. Northern Spring Peeper has smooth skin and x-shaped marking on back (Harding 1997). Ecology Habitat Acris crepitans lives on the edges of ponds and streams with submerged or emergent vegetation (Stebbins 1966). Aquatic Biomes: Lakes and Ponds; Rivers and Streams Trophic Strategy Main diet is insects, including mosquitos. Life History and Behavior Behavior Life span averages four months. With a such a short life span, populations can have a complete turn over in six months. Activity is diurnal. They can jump more than three feet. This would be like a six foot person jumping 200 feet. They can be found basking on sunny banks of shallow pools in groups. Predators include fish, snakes, herons, and minks. To escape predators they jump in a series of zig-zag motions (Barket 1964). Life Expectancy Maximum longevity: 4.9 years (captivity) Observations: In the wild, these animals are short-lived. Even so, their maximum longevity may be underestimated as it is based on only a few captive animals. Reproduction Acris crepitans reaches sexual maturity at one year. Winter to summer, active all year except midwinter in the north. Female responds to male calls April through May and beginning of August. Call sounds like a metallic "gick, gick," resembles steely marbles, lasting approximately one second long. Eggs are less in number than other frogs. One at a time are laid and attached to plants in a pond or pool, while the male releases his sperm. Eggs hatch in a few days. Tadpoles have a black tipped tail unlike any other tadpole. Metamorphosis occurs between July and August (Conant & Collins 1991, Harding 1997). Conservation Conservation Status This species was common until the early 1970's. It is uncertain why the decline happened so quickly. Suspected reasons are drought, increased use of pesticides, fertilization, highway salts and other pollutants. Low populations and short life span limit recovery. Acris crepitans blanchardii disappeared in some sites, but remains common in southern and western regions. This subspecies is listed as special concern in the state of Michigan. It is important to monitor existing populations and to identify and preserve known habitats. MI has a volunteer frog survey program, through the MDNR wildlife division, Lansing. Residents in other states can contact their local DNR.(NPWRC 1999, Harding 1997). IUCN Red List: Least Concern US Federal List: No special status CITES: No special status State of Michigan List: Special Concern Management Conservation Actions The range of this species overlaps with several protected areas. Threats Acris crepitans has declined in the north and northwestern part of its range for various reasons revolving around habitat change (Stebbins 2003). Trends Vocal calls are like the rapid clicking of pebbles, making a "metallic gick gick gick" sound. Rate of vocals is about 1 to 3 calls every second. Breeding period usually lasts from April to July (Conant and Collins 1991). Males can be seen calling from floating vegetation mats or from the banks of ponds. Females seem to prefer males that call at a low pitch. It is active during both day and night in warm weather but only active during the day in spring and autumn. Acris crepitans is an extraordinary leaper and can leap up to 38 times their standard body length (Hammerson 1999). It is carnivorous, eating various invertebrates and arthropods such as beetles, flies, spiders, ants, and true bugs (Hulse McCoy and Censky 2001). Relevance to Humans and Ecosystems Benefits Important to humans for research and management. Used as an indicator species of water quality. Also used to measure pond and stream ecological standards (NPWRC 1999). Risks A. c. blanchardi or Blanchard's Cricket Frog is named after the herpetologist at the University of Michigan, Frank Nelson Blanchard (Conant and Collins 1991). Field Guide Frogs and Toads of the Washington, D.C. Area Field Journal Name: Date: Fowler's toad Location: Anaxyrus fowleri (Hinckley, 1882) Weather: Time of Day: Observations / Data / Activity Overview Distribution This species range occurs throughout most of eastern USA and northern shore of Lake Erie in Canada (Conant and Collins 1991). It is absent from northern New England and Florida peninsula. Ecology Habitat Write down questions that you have for further exploration. Habitat and Ecology It can be found in wooded areas, river valleys and floodplains, agricultural areas, usually in areas with deep friable soils. It burrows underground or hides under rocks, plants, or other cover when inactive. Eggs and larvae develop in shallow water of marshes, rain pools, ponds, lakes, reservoirs, flooded areas, and other bodies of water lacking a strong current. Systems Terrestrial Freshwater Conservation Management Conservation Actions No conservation measures are needed. Threats Major Threats It is not threatened range wide. Trends Population The population is widespread, generally common and relatively stable, with local declines. Population Trend Stable Page 2 Field Guide Frogs and Toads of the Washington, D.C. Area Field Journal Name: Date: Cope's gray frog Location: Hyla chrysoscelis Cope, 1880 Weather: Time of Day: Observations / Data / Activity Overview General Description Hyla chrysoscelis is often confused with Hyla versicolor. The two species are actually identical except in distribution, call, and chromosomal count. H. chrysoscelis is diploid (N=2), where as H. versicolor is tetraploid, (N=4). H. chrysoscelis is a relatively large treefrog that is usually gray or green in color. The exact coloration is determined by the activities and environment of individuals and can therefore vary within the species. All individuals, however, have bright orange or yellow bits of color spotted with black along their hind legs (Conant and Collins 1998). Distribution Write down questions that you have for further exploration. This frog occurs widely across much of the eastern United States. They range from central Texas in the south, as far north as Ontario, Canada and all the way out to the east coast, where they can be found in the panhandle of Florida and up north into Maine (Conant and Collins 1998). H. chrysoscelis is usually found in wet woodlands, such as ponds or swamps (Bartlett and Bartlett 1999) . Physical Description Morphology Cope's gray treefrogs typically measure 3.2 to 5.1 cm long. The largest gray treefrog holds a record of 6 cm. There is no sexual dimorphism. The dorsal surface of gray treefrogs is rough and lightly sprinkled with warts, although smoother than most Bufo. The large toepads produce mucous to adhere to surfaces, including smooth bark or man-made structures, and are characteristic of the family Hylidae. The color of gray treefrogs varies. Factors affecting coloration are substrate, season, and humidity. Shades of gray are most common, with black blotches on the back. Variations of brown, green, and pearl-gray colors have been noted. Green colors are more prominent during the breeding season and in yearling frogs. Usually, there is a white mark beneath the eye. In the region of the groin, the ventral skin on the hind legs may appear orange to golden-yellow with black speckles. The Page 3 remainder of the belly is white. If the coloration is in question, place the treefrog in a box, allow it to sit quietly, and later re-examine the specimen. Yearling frogs are about half the size of the older H. chrysoscelis, but otherwize have the same physical characteristics.

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