The adults generally stay close to water, particularly along sunny shores, under dry summer conditions, but can be found traversing uplands during high humidity.

First, egg masses are deposited in comparatively warm water along gradually sloping shorelines, often over soft substrates protected from severe wave action.

Causes are not fully known, but introduced predators such as trout and bullfrogs, UV-B radiation, diseases, and loss of open meadow habitat due to fire suppression have been suggested.

Fertilizers such as urea may also pose a threat to the Cascades frogs, because the juveniles were not capable of sensing and avoiding toxic levels in laboratory studies.

The main predators of the Cascades frogs are the raccoon, mink, coyote, water bugs (Belostomatidae), garter snakes (Thamnophis sirtalis), and several bird species, such as the sharp shinned hawks, owls, Canada jays, and American robin.

To guard itself from other microorganisms that live in the environment, the Cascades frog produces high concentrations of antimicrobial peptides it secretes from its skin in response to infection or stress.

According to Conlon, "frogs belonging to the genus Rana represent a particularly rich source of peptides with diverse structures and specificities against micro-organisms".

A recently discovered chemical, D-lysine, was produced by adding amino acids to the peptides to help decrease the toxicity to the human cells.