What is the leading cause of death for squirrels?

The leading cause of death for squirrels varies by location and species, but overall the biggest causes are predation, vehicle collisions, and disease, with vehicle collisions being one of the top killers in urban and suburban areas. In wild forests, natural predators like hawks, owls, eagles, foxes, coyotes, bobcats, cats, dogs, snakes, and raccoons kill many squirrels, especially young squirrels and those exposed on the ground. In cities and suburbs, cars and trucks are a major cause of death, as squirrels frequently cross roads and are hit while foraging or dispersing. Other significant causes include starvation and harsh winter weather, especially for young squirrels that fail to store enough food, falls from trees, electrocution on power lines, and disease such as mange, squirrel pox, and internal parasites. For baby squirrels, nest predation by crows, snakes, and raccoons is a major cause. Human-related causes like trapping, poisoning, and habitat destruction also kill many squirrels. In many studies of urban Eastern gray squirrels, vehicle collisions and predation by domestic cats are cited as the two leading causes of death for adult squirrels, while disease and starvation are leading causes for juveniles. Overall, few squirrels die of old age in the wild.