Monday, February 21, 2011

First molt

All elephant seal pups are born with black coats, slightly curly. That's replaced in their first molt, after they are weaned. They get a brown and tan coat, more like the adults, dark on top and light underneath. It's a usual marine camouflage, making them blend into the background for predators. Their dark backs blend into the dark abyss for predators looking down on them from above, their light bellies into the bright surface for predators looking up at them from below.
This one shows the patches of dark skin peeling off, showing the brown coat beneath.
The black coat is also an indicator of maturity to Marine Mammal Center rescuers. Pups rescued before they molt get formula.

Monday, February 7, 2011

Black coat weaners

Elephant seal pups are born with a solid black coat, unlike the brown coat with a light belly and dark back they will acquire. They molt that dark wavy coat after they are weaned. That's the condition of this fat weaner enjoying the sun today on the beach.

The black coat is technically considered lanugo, a preliminary coat. Even humans have a lanugo stage during fetal development. Elephant seals keep theirs after they are born.

The black skin peels off, revealing a silvery coat. Marianne Riedman in her book on The Pinnipeds reports that males molt later than females, so perhaps this one is a female. It's hard to tell with youngsters. Females also get teeth sooner than their brothers.

Friday, February 4, 2011

Elephant seal daycare

On Monday, I stopped at Hearst Beach, San Simeon Cove on my way up to the bluff. That’s where the man was attacked last month. State Parks has asked for volunteers to spend time there, to educate the public about the seals that are increasingly resting there.

Ranger Jose Lopez happened to arrive at the same time I did, so I joined him in driving down the beach to see how many were there. We counted seven adult seals on the beach.
He honked at them. They sure don’t like the truck. Several roused themselves as the truck drove past and a couple opened their mouths. I’m not sure whether it was a threat or not. I was glad I was in the truck and not on foot! How terrifying it would be to be attacked.

That wildlife/human interface is always troublesome.

At the Piedras Blancas bluff, thousands of seals are doing well. Many youngsters have already been weaned and are on their own. Some are still being born. I saw several newborns on the beach, although I didn’t witness any births that day.

These two mothers have attracted 11 pups! It made me wonder if there is any kind of reciprocal caring going on. Cows babysit for each other. I’ve never heard it described, but elephant seal mothering is far from completely understood. This looks like elephant seal daycare.