Mother Nature’s big show is in full swing on the beaches at the Piedras Blancas elephant seal viewing areas. The sand is covered from the shoreline to the bluff with females nursing their pups, and the huge males are posturing, chasing, bellowing and fighting as the mating season gets underway.
The mothers feed their pups for about a month and then go into estrus and mate again. The first pups were born in mid-December, so many of the females are ready. This is what the males have been waiting for.
An alpha male may have 40 or more females with pups in his harem and he expects to mate with each mother as she weans her pup. But there are other males on the beach, and he will be busy keeping them away from “his” females.
Most of the interlopers will be younger and smaller, and all he will have to do is raise his head and give them a stern look and they will slink away. Yet there is a threat that he will be evicted from the harem by a bigger, more dominant male.
The first demonstration of dominance is not merely size, but voice. Stretching his neck upward and making his indescribable sound may send other males scurrying away — or not. There may be one that answers him in a bigger voice, and he will back off. If they decide they are well matched, they may fight.
I read an interesting article recently about the vocalizations of male elephant seals. Researchers set up a speaker on a beach with a recording of one male’s vocal threat. A male approached the speaker, it made the sound, and the seal turned and headed for the sea. Later another male approached, the speaker made the same sound, and the seal attacked the speaker and knocked it over.
The “I’m bigger than you” threat of an adult male is difficult to describe. It has deep bass undertones and almost percussive, drumlike accents. Someone once said it sounds like a Harley revving up in a gym.
Though the threats may sound alike to us, it’s apparent from their reactions that the individual voices have strong meanings for the seals.
Some of the mothers have mated and left the beach, heading northward in the sea to eat again after fasting while birthing and nursing. A mother may lose as much as 20 pounds a day while nursing, and the pup may gain as much as 10 pounds a day as the milk can reach 60 percent fat near the end of the nursing period. The females leave their fat weaned pups, now called weaners, behind to learn to swim and fend for themselves after only a month of mothering.
So now the beach is populated with mothers and pups and some plump weaners, often huddled together to stay out of the way of the action of the mating season. The males are providing most of the action as they bellow and chase each other. And then there’s the mating itself — often explicit sex on the beach. As one young student in a school group observed: “We even saw his manly part.”