| AMPHIBIANS - INFO |
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| Description The Tiger Salamander,the terrestrial adult is usually 200-300 mm in length and 40-70 g in weight. It has a primarily dark olive to dark grey or brown background colour with lighter olive to yellow spots. Newly hatched larvae measure 9-15 mm in length, are silvery grey, and have three pairs of feathery external gills. Habitat The species occurs in montane, aspen parkland and grassland regions. Key habitat features include friable soil for burrowing, fishless semi-permanent to permanent water bodies for breeding, and possibly small mammal burrows for daily cover and suitable over-wintering sites. Biology Shortly after hatching, larvae first begin to grow their front limbs, followed by the development of the hind limbs. In the presence of high larval densities, especially when there is a whole range of larval body sizes in the larvae population, cannibalistic larvae may develop, eating other salamander larvae, including individuals as large as themselves. During metamorphosis, larvae resorb their gills as well as their caudal and dorsal fin membranes. Sometimes, certain individuals do not undergo metamorphosis, but become sexually mature in larval form. These adults are referred to as neotenes. Both types of adults may be found in a single population, although a given population is usually composed predominantly of either neotenic adults or terrestrial adults. |
| Description The northern cricket frog is a small, semi-aquatic frog with a "warty" appearance and a pointed snout. The frogs are brown or grey, with a V-shaped mark between the eyes, faint markings on the back, and a broad dark stripe on the long back legs. The back feet have webbed toes. The breeding call of the male frog sounds like pebbles being rapidly clicked together. Adults measure 16 to 38 mm in length. Habitat Northern cricket frogs inhabit the margins of water bodies, such as lakes, ponds, rivers, streams, and, sometimes, temporary ponds and rain pools. On Pelee Island, they have been found in shoreline marshes, pools, lagoons, drainage canals used for agriculture, ditches and flooded fields. They are usually found on muddy shores or in aquatic vegetation in shallow waters. Biology Northern cricket frogs in Canada breed in June and July. The frogs attach their eggs to vegetation below the water surface. Tadpoles metamorphose in 5 to 10 weeks. The juvenile frogs reach sexual maturity shortly after transformation from tadpoles. Northern cricket frogs hibernate under rocks or logs, or in depressions, holes and cracks in the shoreline, but away from water. |
| Description The Northern Leopard Frog is a medium-sized frog characterized by conspicuous dark dorsal spots bordered by light-coloured rings. It has a whitish belly and prominent light-coloured, dorsolateral folds. Its dorsal background colour is commonly green, but may be brown. Adults range from 50 to 100 mm in length from snout to vent. Females are larger than males, but males have larger forelimbs. Habitat A typical breeding site for this species is a temporary pond about 30-60 m in diameter, 1.5-2.0 m deep, located in an open area, and lacking fish. The presence of significant vegetation seems to be important. In the summer frogs are found in a variety of habitats, but usually not in heavily treed areas, in grass that is more than a meter tall, or in open sandy areas. Preferred habitat seem to be in vegetation 15-30 cm tall. Well-oxygenated water bodies that do not freeze solid are preferred for overwintering. Biology Northern Leopard Frogs emerge from overwintering ponds when the water temperature rises to 7-10�C; they then migrate to breeding ponds. A female mates only once and lays a single egg mass, which is attached to submerged vegetation or laid at the surface. Individual females commonly lay around 3500 eggs. Hatching success is generally high. Tadpoles (larvae) can hatch in 9 days or less; after 2 or 3 days the tadpoles become free-swimming. Tadpoles are aquatic, primarily herbivorous, and few survive the summer. At 20�C, it takes them around 90 days to grow to sexual maturity (become semi-aquatic frogs). The frogs typically spend more than 95% of the day sitting in a small clearing of damp soil in leaf litter. In overcast, rainy conditions they hunt for moving prey of accessible size, mostly arthropods. In the fall they move to overwintering sites. They hibernate in small circular excavations in the surface of the mud. The mortality rate of the adults is about 60%. |
| Description The Oregon spotted frog is 6-8 cm long and has short legs, upturned eyes and a brown to reddish brown head and back. These become increasingly red with age. Scattered on this dark background are black spots with light centres. Light brown to orange folds begin directly behind the eye and extend backwards over the tympanum (external eardrum) and to the middle of the back. Beyond that, the folds become discontinuous and disappear as they approach the lower back. Adults have a distinctive belly mottled with dark spots and a fragmented yellow, salmon or red-orange colour wash on the undersurfaces of the upper thigh and belly. Juveniles are olive green or light brown and do not show the belly mottling. Habitat This species requires large warm-water marshes, with emergent vegetation, sometimes within forested landscapes. Shallow ephemeral pools and small floodplain wetlands associated with permanent water bodies are important habitat features. Biology The Oregon spotted frogs are aquatic frogs. It is unknown where the frogs overwinter. The life cycle begins when the frogs become active in late winter or very early spring. Males move to breeding sites, congregate very close to one another and call to female frogs during the day. When ready to lay their eggs, female frogs move towards the calling males. Female frogs lay a single annual egg mass per year, which is fertilized externally by a male. Usually egg masses numbering 600-700 eggs are laid communally, sometimes one on top of another in tight groupings. Single egg masses or groups of only 1 or 2 masses are uncommon. Embryos develop, hatch and become free-swimming aquatic larvae in 14 to 28 days, the exact duration being temperature dependent. In as little as four months, the tadpoles metamorphose into 30-33 mm long froglets and become sexually mature, beginning to breed in their third year. However, the tadpoles are vulnerable to freezing and desiccation, and mortality rates can be high, with all egg masses or tadpoles dying in some years. The lifespan of the species is unknown. Oregon spotted frogs eat beetles, spiders, flies, ants, and water striders. Tadpoles feed on algae, decaying vegetation, and detritus. The Oregon spotted frog is closely related to the Columbia spotted frog (Rana luteiventris). Before they were differentiated through protein analysis in 1997, the two were know collectively as a single species, Rana pretiosa. |