Young elephant seals are arriving daily at SLO County beaches. This is why

Young elephant seals, both males and females, arrive daily on the beach at the Piedras Blancas rookery north of San Simeon.

It’s the Fall Haul-Out, a rest for the young seals between migrations. They’ll continue arriving through October.

Seals fast for the four to six weeks they are on the beach during this autumn retreat. They rely on their blubber to meet their nutritional needs.

The juvenile seals have the beach and the surf to themselves, before the adult male bulls begin arriving around Thanksgiving for the breeding season. Some seals may stay on the beach into December.

Heavy equipment seen in San Simeon

This year, the seals are accompanied by construction crews.

The culvert under the north boardwalk collapsed during January’s big rain storm. California State Parks workers are replacing it.

Seals remain nearby, ignoring the workers, who have fenced off their work area.

Crews will turn to the south boardwalk to replace a culvert after the north boardwalk is reopened.

Part of the north boardwalk is open, accessible from the north parking lot.

That parking lot also leads to the Boucher Trail, two miles to the Piedras Blancas Light Station. Several points along that trail overlook elephant seal beaches.

The light station is open for tours by reservation only on Tuesdays, Thursday and Saturdays.

Book ahead through recreation.gov.

Male elephant seals spar at SLO County beach

The young male seals are willing to spar with each other, on the sand and in the water.

It’s the nature of young guys to roughhouse. Some nose around young females, but they aren’t willing to mate.

The ones on the beach are too young, and they have an estrus breeding cycle. Like dogs, they only mate when they are ready.

The seals take a rest between their two annual migrations.

The young seals will leave the beach as adult bulls arrive in late November, migrating north and west until time to return to the beach to molt their skin in May.

They left the beach in June and are returning now. In between, they were diving and feeding, diving and feeding.

Males and females have different feeding strategies.

Males migrate north along the coastline, diving to feed at the bottom along the continental shelf. Females migrate to the open ocean, feeding on prey they encounter there.

Males eat bottom-dwelling fish such as dogfish and hagfish that are not targets for human tables.

Females eat small fish in the mesopelagic layer. They don’t compete with fishermen, so elephant seals aren’t in conflict with them the way sea lions are.

Adult females on SLO County beaches during haul-out

Occasionally a mature female who is not pregnant comes onto the beach during Fall Haul-Out. Nearly all mature female seals are pregnant every year, but some skip a year.

Exactly why these females aren’t pregnant is a subject of active research at Ano Nuevo Reserve and Sonoma State University.

Tracking individual seals and understanding what’s going on is difficult, but researchers are making progress.

“We had our first adult female satellite tag recovery procedure last week,” Patrick Robinson,

director of the Ano Nuevo Reserve, wrote in an email. “She was not pregnant, but otherwise seemed healthy. We’re still learning about these seals that skip breeding!”