In Katmai, cubs will generally stay with their mothers for 2.5 years. During a cub’s first year of life they are considered cubs-of-the-year (COYs) or spring cubs. In their second year they are generally called yearlings and will den with their mother for at least one more winter.
Katmai’s bears generally separate from their cubs in May or June of a cub’s third summer. The female probably uses threats or aggression to cause the young to disperse. Some females, however, will keep their cubs through a third summer before pushing them away the next spring. (Read more here.)