El Niño Shaping 2018-2019 Elephant Seal Breeding Season

A female elephant seal displays a vocal protest during mating.

NPS / Sean Pickton, NMFS Permit No. 21425

February 2019 - It has been an exciting breeding season for elephant seals at Point Reyes National Seashore. First, there was their spectacular take-over of Drakes Beach at Ken Patrick Visitor Center. A record of at least 52 pups were born on this section of beach, where only three had been born previously in 2017. Then, in the first week of February, preliminary total seal counts hit a peak of 2,444 seals, surpassing last year’s record of 2,411. Peak pup counts, however, do not seem to have surpassed last year’s record.

Newly tagged weaned pup in front of the Ken Patrick Visitor Center.

NPS / Marjorie Cox, NMFS Permit No. 21425

While the Drakes Beach take-over may have been partly shutdown inspired, this year’s weak El Niño may also deserve some of the blame. The El Niño helps explain why there have been so many storms this season. Stormy weather means strong waves that can completely engulf narrow beaches. This can drown elephant seal pups that cannot yet swim, or separate pups from their moms before they are done nursing. Such narrow beaches in the Point Reyes Headlands have been attractive to pregnant female elephant seals in the past. But this year, early storms convinced many females to move to new, safer areas, such as Drakes Beach in front of the Visitor Center. Many females that didn't leave the narrow beaches lost their pups in the other storms that followed. It's too early to estimate how many pups died this year, but the El Niño may have already left its mark in the season’s not-quite-record-breaking peak pup counts.

Molted, weaned elephant seal pup in a "weaner pod." Weaned pups are now in the majority on Point Reyes beaches.

NPS / Marjorie Cox, NMFS Permit No. 21425

With only a couple weeks left in the season, female elephant seals are heading back to the ocean in droves for their first meal in a month. Weaned elephant seals pups are now in the majority on park beaches, as they continue to grow and develop before their first foraging trips. The road to Drakes Beach remains closed on weekdays, and open 9 am – 5 pm on weekends, with no beach access.

Check out the latest Weekly Elephant Seal Monitoring Update to learn more, or contact Sarah Codde with any questions.

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