Nests can also be built in the branches of trees. They are usually lined with shredded bark, grass, moss, and lichen. Gray squirrels breed from January through September. Females have one litter a year, with 3-4 young being born in the period of March through June. Gestation lasts for 43-44 days.
Predators are coyotes, foxes, bobcats, martins, and large hawks.
Occasionally they become pests in nut and fruit orchards, as they may damage the crops. Local populations are sometimes decimated by disease. Population numbers can be reduced by snag removal. The most important conservation effort is to ensure a good number of snags within riparian and conifer habitats in the Carson Range.