Northern red-legged frogs are typically associated with shallow-water ponds and wetlands with emergent vegetation. For breeding, they require forested sites with exposed (sunny), still-water habitat. Breeding habitat may be seasonal or permanent, provided the water persists at least 5 months in duration. Adults and juveniles also use moist riparian and upland forests.
Limiting factors
Loss of egg-laying habitat is widely cited as a key limiting factor, though impacts to active-season habitat may have more direct effects on populations. Hydrologic modifications, fragmentation by roads, suburban development, and other land use changes are among these impacts. Predation and competition by invasive fish and bullfrogs present further threats.
Data gaps
Increase knowledge of basic life history, including habitat use, phenology, and relationships to hydrology. Clarify impacts of pollutants and parasites on this species. Identify seasonally important habitat components and overwintering areas. Conduct baseline monitoring across a range of reference and other sites to gauge habitat quality and associated carrying capacity of different habitat types and conditions. Understand how this species responds to restoration activities and how riparian buffer widths affect population parameters.
Conservation actions
Revise wetland hydroperiod requirements for mitigation and other created wetlands in occupied areas to reduce 'population sinks'. Create upland buffer and aquatic habitat retention requirements for housing developments to minimize local extirpations in the Willamette Valley. Identify regionally important sites to the species and maintain connectivity between them. Maintain wetland habitat with emergent plants and adjacent forest. Address barriers and/or culverts at key road crossings to reduce mortality of lowland (Willamette Valley and Coast Range) frogs. Control bullfrogs and invasive fish at priority sites.
