July, with peak activity occurring in April. Timing of egg-laying activity varies with elevation and weather conditions. In Colorado, initiation of breeding was correlated with the onset of warming weather and initiation of snowpack melting. Eggs are usually laid in late May or early June. In western Montana, a few males were present on the shores (of two gravel pits) by May 11, 1967, and by May 14, each pond contained at least 30 males. Males were spaced at least apart, all facing the shore Eggs are laid in gelatinous strings of 13 to 52 eggs per inch (), in masses of up to 16,500 per clutch. Egg development rate is partially dependent on temperature; hatching times vary. Metamorphosis is usually completed within three months of egg laying. The time required for metamorphosis is given as 30 to 45 days for the boreal toad and 28 to 45 days for the California toad. Female western toads at least 10 to 11 years of age have been reported. In Colorado, boreal toads probably attain a maximum age of at least 9 years. Preferred habitat Western toads are widespread throughout the mountainous areas of northwestern North America, ranging from sea level to elevations near or above regional treeline, or 10,000 feet (305–3,050 m) in elevation. It is uncommon at the higher elevations. Elevational range in Colorado is from about . In the mountains of Colorado, the largest western toad populations usually occur from about elevation. Western toads occupy desert streams and springs, grasslands, and mountain meadows; they are less common in heavily wooded regions. They are usually found in or near ponds, lakes (including saline lakes), reservoirs, rivers, and streams within the above-mentioned habitats. Under laboratory conditions western toads were able to survive in 40% seawater, but died within a week when exposed to 50% seawater. In Colorado, individual western toads typically maintain distinct ranges which vary greatly in size according to the condition of the habitat. Breeding males may exhibit territoriality, especially in areas where breeding sites are scarce. Populations of western toads have very limited dispersal, particularly in rugged terrain. Western toads require open water for breeding. All breeding members of a local population tend to lay their eggs in the same location, which is used repeatedly from year to year. For example, at one site on a permanent lake in the Oregon Cascade Range, western toads returned each year