Limited data from tagging and radio-tracking studies suggest that site fidelity may be interrupted by human disturbances. At birth calves of both sexes weigh anywhere from 100 to 150 lbs and are approximately 4.5 feet in length. After the first few years of life, the growth rate of females declines rapidly until a maximum body size is reached by approximately 10 years of age. Adult females are generally smaller than males, with an average weight of about 1900 lbs and an average length of approximately 9 feet. Although females reach sexual maturity at approximately 4-5 years of age they do not reach their full reproductive potential until they are nine or ten years old.
Male walrus tend to grow faster and larger than females.
After a secondary acceleration of growth, males reach a full adult body size at 15-16 years of age. The tusks are used in intra-specific threat displays and fighting that is most severe in the case of breeding males. Raised nodules on the skin of the neck and shoulders develop only in sexually mature males. Adult males average over 2,700 lbs in weight and 10.5 feet in length. Males tend to become fertile at 5-7 years of age but are likely unable to compete for mates until they reach full physical maturity at approximately 15 years of age.