Elep seals

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ELEPHANT SEALS
Michael Ellis

During the late 70’s I volunteered for the Pt. Reyes Bird Observatory to help monitor the relatively new elephant seal colony on the Farallon Islands, a 100 acre chunk of granite about 24 miles west of San Francisco. I just did whatever the biologists asked me to do. But one of my specialties became timing copulations (averaged about 8 minutes if I recall).

Northern Elephant seals were nearly hunted to extinction for their blubber. By the end of the last century there were less than 100 in the entire world and these were confined to the remote Isla Guadalupe well off the coast of Baja California. It took a garrison of Mexican troops to protect these few remaining animals from the sealers and even scientific collectors. Given this protection the population has rebounded with vigor and there are now well over 150,000. That is a lot of fat.

The colony I was studying had spilled over from the larger and more famous colony at Ano Nuevo off the San Mateo coast. And since about 1979 or so there has been a small but rapidly growing colony at the Pt. Reyes Headland. The National Park Service for years didn’t really advertise this colony. I don’t blame them. It was located at the base of a very steep and dangerous cliff. And there is a distinct management problem trying to keep the curious public away from a beach full of these amazing animals. But last year the Park finally relented and a newer, more accessible, colony was even described in Sunset Magazine, certain doom for any great secret.

After leaving the breeding grounds Elephant seals swim 5000 miles far out into the Northern Pacific where they feed mostly on deep dwelling squid and sharks. Depth gauges attached to the seals reveal that they spend about 90% of their pelagic lives at depth. No one knows how or if they even sleep. They routinely dive to 3 and 4,000 feet, but given that their primary predator is the great white shark, a surface feeder, this seems like very prudent behavior. But they are onshore now lounging, mating, nursing, fighting, snorting, sleeping and will be until mid March or so. Go check them out, the cat, er seal, is now out of the bag.

This is Michael Ellis with a Perspective.

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December 1, 2010