2016 Elephant Seal Breeding Season Update January 8, 2016

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1 216 Elephant Seal Breeding Season Update January 8, 216 The elephant seal breeding season began in December, with pregnant females arriving to give birth on Point Reyes beaches. The first pup of the season was born on December 19, 215. In the 3 weeks since, there have been over 7 more pups born here, a number that will continue to rise in the next few weeks. The first pup of the season, pictured with its mother and a nearby vocalizing male. Photo by Samantha Mutschler. This week at Drakes Beach, a breeding colony at Point Reyes. Photo by Samantha Mutschler. NMFS Permit No

2 215 Elephant Seal Breeding Season Update Males have also begun to arrive on the beach, in hopes of reproducing with the females here. Male elephant seals fight often to establish a dominance hierarchy on the beach. The male who wins these fights becomes the alpha and will defend a harem of females. Researchers at the park are beginning to dye mark a few of the large male seals, in an effort to keep track of their movements on the beaches. Two male elephant seals, note their dye marks on their lower backs, near their flippers. Photo s by Sarah Codde and Samantha Mutschler.

3 You may have heard On December 28, 215, a pregnant elephant seal caused some trouble when she wandered onto Highway 37 in Sonoma County. After more than a day of trying to get her back in the water and leave the area, The Marine Mammal Center brought her here to Point Reyes, where she gave birth on January 2. Tolay and pup (left pair) relax on Drakes Beach, surrounded by other mothers and pups. Photo by Samantha Mutschler. NMFS Permit No Tolay and her pup vocalize, strengthening the bond between them. Photo by Jim Rolka. The seal, nicknamed Tolay, and her pup have been spotted several times this week by researchers at Drakes Beach and is exhibiting normal seal behavior. Elephant seals are extremely vocal, and use their voices to demonstrate dominance, form bonds (see top photo), and several other behaviors. Photo by Jim Rolka.

4 Storms and Elephant Seals As seen in the photo, Point Reyes beaches are heavily impacted by high tides. When tides are particularly high (during high surf and storms), elephant seals are forced into tight groups at the cliff base. Pups are extremely vulnerable to high tides, as they are not old enough to swim yet. Due to the storms and large swell this week, mothers may be waiting for better weather to haul out and give birth, resulting in lower numbers than this time last year. Drakes Beach is located in Drakes Bay, allowing for more protection from the storm surges, which is what drove the elephant seals to colonize this site in 1995 (a year with heavy storms). This week s storms appear to be encouraging more seals to haul out at the Drakes site instead of the oceanfacing sites, resulting in higher numbers there than this time last year.

5 No. Seals TOTAL SEAL COUNT Seals 215 Seals

6 No. Females TOTAL FEMALE COUNT Females 215 Females

7 No. Pups 7 TOTAL PUP COUNT. 6 5 Pups 215 Pups

8 No. Seals DRAKES BEACH COLONY TOTAL SEALS DB Seals 215 DB Seals

9 No. Females DRAKES BEACH COLONY FEMALES DB Females 215 DB Females

10 No. Pups DB Pups 215 DB Pups

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