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Tiger salamanders are biologically well adapted to the dynamic physical and chemical characteristics of prairie wetlands, while major aquatic predators and competitors such as fish are poorly adapted to their harsh chemical environment and recurring drought (Peterka 1989). Larval tiger salamanders have been collected in West Stump Lake, ND, in water with specific conductivities of 12.5 mS/cm (Deutschman and Peterka 1988). Larval densities in North Dakota wetlands can exceed 5,000/ha and maximum annual production of 565 kg/ha has been recorded (Deutschman and Peterka 1988). Salamander larvae at high densities are an important component in the energy flow of the wetlands they inhabit.

Amphipods (Gammarus lacustris) accounted for 78% of the volume of food items in stomach contents of salamanders in North Dakota (Myers 1973). Gammarus spp. tend to occupy wetlands that function as throughflow systems; these wetlands are relatively stable and low in salts. Large salamander larvae (neotenics) occasionally overwinter in wetlands and at this time can impact the invertebrate community.

Aquatic birds that normally feed on fish also feed on larval salamanders. Wiedenheft (1983) reported finding wounds on the dorsal surface of the tails of 10% of a salamander population. Potential predators include the grebes, herring gulls (Larus argentatus), American white pelicans (Pelecanus erythrorhynchos), double-crested cormorants (Phalacrocor axauritus), and black-crowned night-herons (Nycticorax nycticorax).

Leopard frogs have an immense range in North America. On the Dakota prairies, these frogs seem to prefer temporary and seasonal wetlands for courtship activities, but lay most of their eggs in semipermanent wetlands where the tadpoles require about 3 months to metamorphose into adults.

The diminutive chorus frog is found over most of North America. The frogs congregate to breed in the early spring in seasonal and semipermanent wetlands. After breeding, they wander away from water bodies, but still require damp places to avoid desiccation.