Abstract
We analyzed post-mortem measurement data on the external morphology of 22 captive sea otters Enhydra lutris in Izu Mito Sea Paradise, Shizuoka, Japan from 1988 to 2005. Growth curves calculated from the length at age data indicated that males grew faster and larger and exhibited sexual dimorphism in body size. Male and female growth rates estimated in this study were equivalent to or higher than those recorded in wild sea otters under good nutritional conditions. Allometry of body parts relative to body lengths was analyzed using generalized linear models and model selection. Sexual differences in allometry patterns were not apparent. Head, mouth, forelimb and palm showed negative allometory, and hindlimb and tail showed isometry. The negative allometric patterns of head and limb appear to be related to the adaptation of precocial young to aquatic life.
