How much does a Northern fur seal weigh?



Male Northern fur seals can weigh 5-6 times as much as their female counterparts! A female may only gain and lose 10-20 pounds throughout the year, while adult males can gain and lose over 250 pounds in one year! During the early summer, Northern fur seals return to islands in the North Pacific to breed. Males come ashore to defend territories with the largest and strongest males attracting the most females into their harem. For more interesting facts about our Northern fur seals, go to

Can you guess how much Commander weighs? Place your guess here and visit us April 13-15 for Marine Mammal Mania! Commander will be weighed at 11:30am each day. Come see if you guessed correctly and for more information about the hands-on activities, special talks and demonstration during Marine Mammal Mania, go to!

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