The Elephant SealMirounga anustirostris

Pinnipedpinna = feather or wing

pedis = foot

• Fin footed marine mammal

• Four limbs modified as flippers

• Streamlined body

California Pinnipeds

• Eared Seals– External ear flaps– Fur seals and sea lions– Hind flipper turns forward

• Move about on land quickly• Sea lions = circus seals

• True Seals– Harbor seals & elephant

seals– Lack external ears– Clumsy on land

Elephant Seal

• Largest pinniped

– Males 14-16 ft long, 3,000-5,000 lbs

– Females 9-12 ft & 900-1000 lbs

• Northern elephant seal ranges from Baja, CA to Vancouver Island

• Diet of squid, small shark & fish

• Sexual dimorphism

Annual Cycle

• Bulls arrive in Dec – stake out territory• Only 6% of males will get lucky ( a harem)• Pregnant females begin to arrive in late

Dec & Jan• Females will give birth to pup within 3

days after arriving on beach• Pups nurse for about a month

– Will quadruple weight– Moms milk is 55% fat

Northern Elephant Seal Life Cycle

• Females nurse young for about a month

• Babies wean – “weaners”• Moms come into estrus• Mate before leaving• Females fast while on

beach

• Weaners live together for about 2 months• Learn to swim and leave the beach• Mar-May spring molt• Jun – Aug Summer molt

Piedras Blancas Rookery

• Less than 25 seals on beach in 1990

• First birth in 1992• 50 pups born in

1993• By 1996 >1000

pups born– Population

explosion!

Directions

• Hwy 1 North, about 42 miles north of Cuesta College

• Left turn out – you will see pine fencing• If you go past the lighthouse – you’ve

gone too far• Park at the north end of the parking lot