In Alberta, most live in clear, clean freshwater springs in lightly wooded areas. They're most active after sunset in warm, wet weather. They winter under stones in the moving water, as long as there is enough oxygen. These are the familiar frogs of biology books and laboratories. They are the largest common frogs at 50-130 mm long.
Tadpoles eat plants, algae, some dead tadpoles or other small, dead invertebrates.
Adults eat almost anything they can catch, including insects, other invertebrates and small vertebrates such as mice or fish. In late April, males begin calling to attract females. The eggs hatch in 10-20 days into tadpoles. By early August, they transform into adults. Scientists can't explain the worldwide disappearance of many amphibian and reptile species.