2019-2020 Elephant Seal Breeding Season in Full Swing

Male elephant seals are establishing dominance hierarchies, with the biggest of them achieving alpha status over groups of females. Biologists dye-marked more than 40 adult males to track how they move around the colony over the course of the season.

NPS / Marjorie Cox, NMFS Permit No. 21425

January 2020 - The northern elephant seal breeding season is now in full swing at Point Reyes National Seashore, and biologists in the park have been busy monitoring the season’s progress. Pregnant females are arriving in great numbers after many months at sea foraging. Males are establishing dominance hierarchies, with the biggest of them achieving alpha status over groups of females. Biologists used black human hair dye to mark more than 40 of them with unique letter-number combinations on their rumps to track how male elephant seals move around the colony over the course of the season.

The first elephant seal pup of the season was born at the Historic Lifeboat Station on December 22, 2019. As of January 24th, there were roughly 700 pups on Point Reyes beaches, and around 2,100 elephant seals overall.

Jessica Weinberg McClosky, NMFS Permit No. 21425

The first pup was born at the Historic Lifeboat Station on December 22, 2019, and was weaned on January 20, 2020. King tides coincided with calm seas during the second week in January, leaving seals on the park’s most vulnerable beaches with enough space to stay mostly dry. When such tides combine with stormy weather, they can wash out entire beaches, drown elephant seal pups, and cause pregnant females to move to more sheltered beaches. As of January 24th, there were roughly 700 pups on Point Reyes beaches, and around 2,100 elephant seals overall. These numbers are lower than the past two years, but this is likely because of a later than normal start to the breeding season.

Learn more about the season so far from the Weekly Elephant Seal Monitoring Update. These updates include new photos every week, regularly updated graphs, and lots of fun elephant seal facts and research highlights. Contact Sarah Codde with any questions.

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