1. (C) 2008 California State Parks 1 Northern Elephant Seals Factoids

2. (C) 2008 California State Parks 2 Taxonomy Class: Mammalia Class: Mammalia Order: Pinnipedia Order: Pinnipedia Family: Phocidae Family: Phocidae Genus / Species: Mirounga angustirostris Genus / Species: Mirounga angustirostris

3. (C) 2008 California State Parks 3 Diving Can dive to more than 5000 feet (average 1000 – 2000) Can dive to more than 5000 feet (average 1000 – 2000) 2nd deepest diving animal in the ocean 2nd deepest diving animal in the ocean Sperm whale can dive more than 1-1/2 miles Sperm whale can dive more than 1-1/2 miles Average dive: 20 minutes Average dive: 20 minutes Longest known dive: 2 hours Longest known dive: 2 hours Less than 5 minutes on surface between dives Less than 5 minutes on surface between dives Swim 10 – 15 mph Swim 10 – 15 mph

4. (C) 2008 California State Parks 4 Breeding, Birth & Growth First males arrive December First males arrive December First females late December First females late December Gives birth 3 – 6 days later Gives birth 3 – 6 days later Gestation 7 months but… Gestation 7 months but… Delayed implantation  5 months Delayed implantation  5 months

5. (C) 2008 California State Parks 5 Breeding, Birth & Growth Females reach sexual maturity at 2 years old Females reach sexual maturity at 2 years old Begin giving birth at 4 years old Begin giving birth at 4 years old Males reach sexual maturity at 6 or 7 Males reach sexual maturity at 6 or 7 Males normally mate at 9 or 10 Males normally mate at 9 or 10

6. (C) 2008 California State Parks 6 Breeding, Birth & Growth Breeding season Breeding season December through mid-March December through mid-March Average harem: 20 females Average harem: 20 females

7. (C) 2008 California State Parks 7 Breeding, Birth & Growth Females come into heat 19 days after giving birth Females come into heat 19 days after giving birth Receptive only 4 days Receptive only 4 days

8. (C) 2008 California State Parks 8 Breeding, Birth & Growth 2/3 of males don’t breed 2/3 of males don’t breed Milk is 54.5% fat Milk is 54.5% fat Richer than any other mammal Richer than any other mammal Adults may lose 50% of body weight during breeding season Adults may lose 50% of body weight during breeding season

9. (C) 2008 California State Parks 9 Molt Molting Molting Females: April / May Females: April / May Young males: May / June Young males: May / June Adult males: July / August Adult males: July / August Stay in muddy water, beach Stay in muddy water, beach “Catastrophic” molt “Catastrophic” molt

10. (C) 2008 California State Parks 10 Annual Cycle - Male Life span: 14 years Life span: 14 years Maturity: 9 years old Maturity: 9 years old 8 months at sea 8 months at sea 4 months post breeding 4 months post breeding 4 months post molt 4 months post molt On land On land 3+ months for breeding 3+ months for breeding 3-4 weeks for molt 3-4 weeks for molt

11. (C) 2008 California State Parks 11 Annual Cycle - Female Life span: 20 years Life span: 20 years Maturity: 2-4 years old Maturity: 2-4 years old 10 months at sea 10 months at sea 2 months post breeding 2 months post breeding 8 months post molt 8 months post molt On land On land 5 weeks for breeding 5 weeks for breeding 3-4 weeks for molt 3-4 weeks for molt

12. (C) 2008 California State Parks 12 Annual Cycle - Juvenile 10 months at sea 5 months post breeding 5 months post breeding 5 months post-fall haul-out 5 months post-fall haul-out On land On land 1 month for breeding 1 month for breeding 1 month for post-fall haul-out 1 month for post-fall haul-out

13. (C) 2008 California State Parks 13 Annual Cycle - Weaners 5 months at sea 5 months at sea Leave beach 3-1/2 months old Leave beach 3-1/2 months old Return for fall haul-out Return for fall haul-out

14. (C) 2008 California State Parks 14 Time Line November November Sub-adult males haul-out Sub-adult males haul-out Mature males begin to arrive Mature males begin to arrive December December Mature males arrive Mature males arrive Females arrive Females arrive First births mid-month First births mid-month

15. (C) 2008 California State Parks 15 Time Line January January Females continue arriving Females continue arriving Peak of births last 2 weeks Peak of births last 2 weeks February February Births continue Births continue Peak mating mid-month Peak mating mid-month Females leave Females leave

16. (C) 2008 California State Parks 16 Time Line March March Last adults leave Last adults leave Weaners learn to swim Weaners learn to swim April April Females return to molt Females return to molt Juveniles return to molt Juveniles return to molt

17. (C) 2008 California State Parks 17 Time Line May May Females molt Females molt Juveniles molt Juveniles molt June June Sub-adult males return to molt Sub-adult males return to molt

18. (C) 2008 California State Parks 18 Time Line July July Sub-adult males molt Sub-adult males molt Adult males molt Adult males molt August August End of male molt End of male molt

19. (C) 2008 California State Parks 19 Time Line September September > 1 year olds haul-out > 1 year olds haul-out Juveniles haul-out Juveniles haul-out October October > 1 year olds haul-out > 1 year olds haul-out Juveniles haul-out Juveniles haul-out

20. (C) 2008 California State Parks 20 Population Issues 180,000 elephant seals 180,000 elephant seals Population between 8 and 20 100 years ago Population between 8 and 20 100 years ago Hunted for their oil for lamps Hunted for their oil for lamps Majority of hunting over 15 year period Majority of hunting over 15 year period Just like sperm whales Just like sperm whales

21. (C) 2008 California State Parks 21 Population Issues The few remaining elephant seals started a new population and there are now 2 main colonies with other little ones here in Northern California The few remaining elephant seals started a new population and there are now 2 main colonies with other little ones here in Northern California

22. (C) 2008 California State Parks 22 Colonization First on Ano Nuevo in 1955 First on Ano Nuevo in 1955 First pup 1961 First pup 1961 First at Piedras Blancas 25 November 1990 First at Piedras Blancas 25 November 1990 First pup 1992 First pup 1992

23. (C) 2008 California State Parks 23 Colonies

24. (C) 2008 California State Parks 24 Males Females Migration

25. (C) 2008 California State Parks 25 Miscellaneous Meaning of “Año Nuevo” Meaning of “Año Nuevo” First seen by Spanish explorers on 3rd of January 1603 First seen by Spanish explorers on 3rd of January 1603 Northern elephant seal is larger than Southern Northern elephant seal is larger than Southern