Adult harbor seal has sex change
Nov/21/12 01:37 PM
Thanks to better identification photos obtained yesterday, it has been confirmed that Captain, the adult seal who has been using a West Seattle beach for going on several weeks now and at first believed to be a male is, indeed, female! Captain showed up earlier than usual yesterday - in broad daylight - most likely due to riding out an intense storm the night before when she did not come ashore. She is shown here settled in on the beach for a long rest.
Since Captain has been hauling out
either in near darkness or after dark, photos sent to a consulting marine mammal biologist last week for health assessment and evaluation were not terribly sharp - hence the error in gender identification.
It is very difficult to determine sex of harbor seals even with optimum photos since, unlike sea lions, male sexual organs are internal. Additionally, unlike many species, male harbor seals are not significantly larger or exhibit unique physical characteristics. Both Steller and California sea lion males are much larger and weigh hundreds more pounds than females. Male California sea lions develop a bump on their forehead, called a sagittal crest, which indicates sexual maturity (see photo at left taken this morning of a CA sea lion male in Elliott Bay).