Size - The average adult male ranges from 9ft to 11ft and weighs from 1500lbs to 2000lbs. The average adult female can be between 7ft and 8ft and usually weighs about 600lbs. At birth the baby Steller Sea Lions are about 3ft and weight about 45lbs. Reproduction - The Steller Sea Lions follow a defined breeding pattern. They breed between May and June and the male is dominate sex.
Reproduction is sexual.
Dominant males, usually 9 years old and older, establish territories on rookeries in early May, maintaining them for about 40 days without feeding. Individual males hold territories any where from 1-7 years. Reproductive success is greatest for those males holding territories with access to water frequented by females. Most females Steller Sea Lions breed only once. Once the female has been fertilization further development of the embryo ceases.