See bulked-up elephant seals bellow, molt on SLO County beaches

Summer is molting season for northern elephant seal bulls at the Piedras Blancas rookery north of San Simeon. The massive marine mammals are at rest, so it’s an excellent time to view their big noses and chest shields.

All elephant seals molt, or, shed, their skin once a year.

Pups molt when they are weaned, and young seals and females molt in May and June. The bulls molt in July and August.

The elephant seals’ coats range in color from gray to brown and tan, although they look black when they arrive on the beach, wet and shiny.

Last year’s brown layer of epidermis and fur peels off, revealing pearly gray fur underneath. The new coat will become tan and brown as the individual hairs finish growing out and stand up.

Friends of the Elephant Seal docents, identifiable by their blue jackets, can let you handle pieces of the shed skin.

The fur is short and stubbly, often compared to Astroturf. These seals rely on their blubber for warmth, not their fur.

The elephant seals have to stay on the beach while they are molting. Blood flow increases to the new skin, and the seals would lose too much heat in the cold water.

Molting takes about a month for each seal. They come and go individually, so molting seals are on the beach for a couple of months.

Scars last forever, and can be easily visible on the molting seals.

A few survived serious shark bites, and many show battle scars and cookie cutter shark scars. Cookie cutter sharks are small sharks that take a circular plug of blubber from a seal, leaving a distinctive scar.

Bites must have been serious to produce some of these scars, but the seals survived.

Blubber likely doesn’t have many nerve endings. It doesn’t have much blood supply, so the wounds don’t cause major blood loss.

SLO County elephant bulls bulk up

The most dominant bulls spent as long as 100 days on the beach during the breeding season, November through March, defending their harems. They were at their low point in terms of weight.

The bulls have been feeding since they arrived at their northern foraging areas in March, after the breeding season.

They feed along the continental shelf of North America, in Canada and Alaska. They’ll return there after they leave the beach, to feed for another four or five months.

When the bulls return in November and December, they will be at their blubbery maximum.

The pile of bulls now on the beach looks fat and comfortable.

Males bellow in the mist

The beach is relatively quiet in the summer, but some bulls bellow their presence, from the water or on the beach.

Adult bulls have unique calls. They recognize each other, and remember whether they have fought in the past.

Having settled who was the winner in the past, they don’t need to fight again. It helps reduce aggression.

The bulls have to be loud to make themselves heard over wind and surf.

The loudest elephant seal call measured registered at 126 decibels, making it one of the loudest sounds made by mammals on land.

For more on the seals’ vocalizations, watch a Labside Chat video with Caroline Casey, who researched the bulls’ calls, at youtu.be/XHvUGBlztSI.

You can see how she carefully records the seals by watching a video at youtu.be/FpIf6mPZJGA.