Male seals are returning to the beach for their summer molt. As soon as you open the car door in the parking lot, you can hear them bellow.
Most of the seals on the beach in June are subadult males, but a few fully adult bulls have already arrived. More bulls will show up in July and August.
Subadult means that they are growing that distinctive elephant seal nose (technically, proboscis, a long nose) but aren’t fully mature yet. They start growing that nose at 5 years old, along with the calloused skin of the chest shield. They are considered fully mature at 8 years old, with a floppy elephant-like trunk. The proboscis continues to grow throughout their life, so it’s a general indicator of age.
Adult bulls recognize each other’s deep, throaty, pulsing roar. They know each other, and whether they have fought in the past – and who won. They won’t fight each other a second time. That simplifies social relationships. As soon as one hears the victor of the past hold forth, he can escape in the opposite direction.
The youngsters sparring on the beach and hectoring each other may not store memories of those encounters for future reference.
Communicating with each other is more than a matter of dominance. While the seals are on the beach, they need to conserve energy. They don’t eat anything for the four to six weeks they spend at Piedras Blancas molting their skin. During the winter breeding season, males are on the beach as long as three months. They live off their blubber. It’s a long fast, and they don’t have energy to waste. They have several physiological adaptations to conserve energy. Vocalizing is a social behavior that helps them make their blubber last.
Recognizing who is trumpeting a challenge, and who won in the past, means they don’t need to fight it out again. That’s a far better way to organize the beach than attacking each other. They are all under the same limitation: metabolizing their blubber to survive. They are consuming their own bodies while they’re on the beach, sustaining them while they aren’t eating. The less energy they expend, the better.
Bull elephant seals have individual voices and calls. They vary by the pulsing, and have flourishes at the beginning and end of the bellow. It’s subtle to human ears, but meaningful if you’re another bull.
The background noise of wind and surf on the beach washes out sound. Elephant seal bulls are one of the loudest land animals. Their bellows have been measured at 126 dB, past the pain threshold for human hearing of 120 dB. So it’s not surprising you can hear them in the parking lot.
They are on the beach to molt their skin. Their skin peels off once a year, and they spend four to six weeks on the beach looking terrible. Tap a Friends of the Elephant Seal docent, a guide in a blue jacket, and ask to touch some of the shed skin. They carry samples to share with the public.
Christine Heinrichs’ column appears the fourth Thursday of each month and is special to The Cambrian.