Species: Rana pretiosa

The life cycle involves distinct stages: eggs, larvae, and metamorphosed individuals. Breeding occurs as early as February or March at lower elevations and as late as late May or early June at higher elevations (Leonard et al. 1993), and at a particular elevation southern populations likely tend to breed earlier than do northern populations. Breeding occurs in February at sea level in British Columbia. In central Oregon, the period from first oviposition to first hatching occurred in mid- to late April (Bowerman and Pearl 2010). Where freezing occurs, breeding generally occurs as early as winter thaw permits. In at least some areas breeding is "explosive" and occurs primarily within a period of 1-2 weeks (Pearl and Hayes 2005). Reproductive females likely breed once each year and deposit one egg mass per breeding event, and they usually lay eggs communally in clusters containing up to several hundred egg masses, often in the same location year after year. Eggs survive freezing air temperatures and ice cover for up to several days (Bowerman and Pearl 2010), hatch in 3-21 days, depending on temperature. Metamorphosis occurs in mid- to late summer (Nussbaum et al. 1983). Individuals first breed when 1-3 years old (females generally at 2-3 years), depending on the elevation and latitude (mature at greater age at high elevations). Most individuals live not more than a few years, but some may live more than a deacde (see USFWS 2009).