Wednesday, April 27, 2022

Sealstack

April and May are the most crowded months on the beach at Piedras Blancas. All the adult females, over 5,000, plus juveniles of both sexes, arrive for their annual molt. It’s ideal seal watching for every possible variation in coat color and scientific markings.



No adult bulls, though. Some of the young males show signs of growing that distinctive nose, but they are at least two years away from adulthood. The mature bulls are on their post-breeding-season migration, foraging to regain the weight they lost. They may have gone as long as 120 days without food. Time to bulk up.

They feed along the continental shelf on the Canadian and Alaskan coastline. They will return in July and August, to molt their skin.

Molting

The expanse of brown, tan and gray animals looks indistinguishable at first, but let your eyes get accustomed to it. It’s like looking at jigsaw puzzle pieces, Gradually, contrasts emerge.

Shiny black seals just came out of the water. As they dry, their skin looks brown on their backs, tan on the underside. The seals undergo the process of a catastrophic molt once a year. As the old skin peels off, it reveals the new gray skin and brown coat beneath. The hairs of the coat just haven’t dried out and stood up yet. As they do, the coat acquires its brown color.



Compare how the molt happens on different seals. It starts around the eyes and other body orifices, and old scars. Some are pockmarked with scars from cookie cutter sharks, a small shark that bites, twirls around to take a distinctive circular plug of blubber, and leaves with its blubber meal.



They look ratty, but it’s normal. Seals arrive one by one on the beach, and start peeling off their skin within a couple of days. They spend about four weeks on the beach during April and May, so seals are at all stages of molting for the duration.

FES docents have samples of shed skin you can touch and handle. Clean and dry.

Delayed implantation

As females complete their molt, the embryo that started to grow back in January and February, when they mated after they finished nursing this year’s pup, now begins to develop. When they leave the beach this time, it will be for their long migration. They’ll be foraging in the ocean until January, when they return to the beach to have their pups.

Tags and marks

Cal Poly and UC Santa Cruz have research programs that involve identifying individual seals so that their movements to other beaches can be recorded. Look for marks and tags. If a blue-jacketed Friends of the Elephant Seal docent is around, report it to them. If not, take pictures and send them to tags@elephantsel.org. They’ll get back to you for additional information – when and where you saw the seal – and your re-sighting will be part of the database.