site soon after snowmelt. Its breeding season begins once the highest meltwater flow is over, around March through May in the southern part of its range, and up to July in higher mountains to the north. Fertilization is external, and the egg cluster is secured to vegetation in a current, or in still waters sometimes left floating free. How long it takes for breeding onset varies from 1-4 years depending on the levels of snow and temperature. Very cold temperatures may cause death of larvae. The juvenile may be a tadpole for 3 to 4 years before undergoing metamorphosis. However, this rate heavily varies depending on the temperature and elevation of the area. There are two classes of tadpoles: first year tadpoles and second year tadpoles. Metamorphosis tends to happen the second summer of tadpole life. They are called metamorphs when this transition from tadpole to young frog is occurring. They are then called a juvenile when it survives one winter. It becomes ready to reproduce after 2 years of the juvenile stage. It is found that the growth and development rate is slower at higher elevations. Behavior The frog lacks a vocal sac. Its call is raspy, rising at the end. During the day, it calls underwater. The frogs tend to be less active during the winters and more active during the mating season. For years when there is heavy snow at high elevations, they may only be active for 90 days in the summer. Hibernation tends to happen underwater or in the crevices of stream banks. This occurs during the cold months of winter. Hibernation ends in the spring to start the breeding season. This species feeds on aquatic insects and benthic invertebrates. Their diet varies depending on the habitat type. When living in streams, it tends to eat terrestrial insects such as beetles, ants, bees, wasps, flies, and dragonflies. They are also known to eat larvae of other frogs and toads, as well as commit cannibalism. Decline Once a common species, Rana muscosa was absent from much of its native range by the 1970s. Over the course of the last hundred years, 90% of its populations have been eliminated. The frog was known from 166 locations in the Southern California mountains, and as of 2007, only seven or eight remained. The 2009 discovery of R. muscosa at two locations in the San Bernardino National Forest was newsworthy.