Life for a northern elephant seal is a harsh deal initially advertised as a good one. For the first four weeks of their lives, pups live in the shelter of their mothers' protective bulk, nursing on milk so rich they gain 10 pounds a day. After a month the mothers, depleted from the massive intergenerational transfer of blubber, abruptly return to sea to resume the feeding they neglected during their month on land. With that, the party's over.

The fattened young pups are left onshore to figure out for themselves how to enter the water, dive for fish and make a 10,000-mile solo migration that makes their species the unparalleled distance runners of the mammalian universe, outstripping even the accomplishments of the gray whale.

The 25 percent of pups who evade starvation and white shark attacks during this vulnerable period will repeat an astounding annual cycle, migrating to feeding grounds in the Northern Pacific twice each year, diving as deep as a mile for fish and for up to an hour at a time along the way. They'll return to the rookeries of their births once in summer to molt and once in winter to pup and breed. The males, 14 to 16 feet long and weighing up to 5,000 pounds, will battle furiously for mating rights to entire harems of females, which are much smaller at 10-12 feet and 1,200-2,000 pounds. While on terra firma, both sexes will fast.

Their serial migration is a feat that never ceases to amaze Soquel filmmaker Drew Wharton, whose documentary, A Seal's Life: The Story of the Northern Elephant Seal, receives its Santa Cruz premiere Sept. 27.

"It's like if we could swim from L.A. to Boston and back, twice a year, and we were diving 24 hours a day, only surfacing for three to five minutes," he says. "No sleep. They sleep when they dive. And they do it solo. It's amazing, amazing stuff. This is why I filmed these animals."

Wharton's project, three years in the making, claims an impressive lineup of partners and supporters for a first feature film (his business, Wharton Media, specializes in corporate work). It is produced in association with National Geographic's Mission Programs division, features a National Geographic "Crittercam" sequence showing a turbulent journey through the surf from the perspective of a tiny camera mounted on an elephant seal's back, and is narrated in calm, no-nonsense fashion by Dr. Sylvia Earle, former chief scientist of the National Oceanic and Atmospheric Administration.

Wharton credits two things for getting Earle and National Geographic to sign on to his ambitious project. First, he says, A Seal's Life is the first in-depth look at elephant seals for public consumption. Until now, he says, "The only air time they've gotten is as predation for white sharks."

Second, the elephant seal's recent history is a compelling illustration of humankind's capacity for both rapacious greed and redemption. Hunted nearly to extinction for their blubber in the late 19th century, northern elephant seals almost received the coup de grâce in 1892 when researchers from the Smithsonian Institution, euphoric over their discovery of creatures they'd believed to be extinct, killed seven of the nine elephant seals they'd found in the interest of science. The horrific misstep took place on Guadalupe Island, some 150 miles off the Baja Peninsula—home of the last surviving colony of elephant seals.

The species limped along until 1922, when the Mexican government established protection for the Guadalupe Island colony. The United States soon followed suit, and today the animals number somewhere between 125,000 and 175,000.

"This is a great example of a species that we nearly eliminated," Wharton says. "But as easy as it is to eliminate a species, this is also a positive story about how we brought it back with basic protections."

Nature in Flux
The elephant seal is safe for the moment. But scientists at UCSC, the premier institution for studying the creatures, paint a picture of a species still undergoing a massive transition and not entirely out of the woods.

One concern is genetics. The size of the original Guadalupe Island colony, estimated at between 10 and 100 individuals, leaves the seals unusually susceptible to disease.

"Genetic analysis indicates the entire population was sired by one male back at the turn of the century," says UCSC ecology and evolutionary biology professor Dan Costa, who's been studying elephant seals since the mid-'70s. "They're not clones of one another, but they're damn near. The health of the population is the million-dollar question."

Costa says scientists have theorized that the same thing that helped save elephant seals from extinction, and which makes them hard to count—their staggered haul-outs—might keep disease from wreaking too much havoc. Or perhaps their limited time on land keeps them healthy. "Whatever elephant seals are doing, it's the right formula," he says.

One thing is certain: the northern elephant seal is in a dynamic period of habitat expansion as rookeries fill up. The primary breeding grounds have shifted north from Guadalupe Island to San Miguel and San Nicolas, both in the Channel Islands. Piedras Blancas, near San Simeon, is another major rookery; Point Reyes Headlands is another, smaller, breeding site. Costa says one is being established on Vancouver Island.

Strangely, Año Nuevo, the colony most intensively studied owing to its proximity to UCSC, would be shrinking if not for visits from nonnatives.

"Whenever we crunch our numbers, one answer we get is that the Año Nuevo population is not self-supporting," says Pat Morris, elephant seal research coordinator for UCSC. "That colony would go downhill if not for immigration."

Morris says scientists aren't sure what's causing the decline in returns by Año Nuevo natives—shark predation could be a factor—but she points out that elephant seals are a relatively recent arrival at Año Nuevo and other mainland California sites. "Until 30, 40 years ago, these animals only used islands," she says, "because on the mainland there were grizzly bears and mountain lions.

"If you look at middens in Northern California, you will not see elephant seal bones," she says. "You will see fur seal bones. Seen any fur seals lately? No. So our population of pinnipeds in Northern California has changed very dramatically, and we don't know why."

Costas says elephant seals are an extreme example of all natural systems, which are never static.

"Elephant seals are definitely in flux," Costas says. "You could say that about a lot of wild systems, but it's not as obvious because things aren't changing as fast."

Ambassador for Action
Drew Wharton's film doesn't attempt to answer these questions. It's an educational outreach tool that he hopes will inspire both kids and their parents to support oceans conservation. He's making the film available to a number of entities to sell in gift stores and visitors centers, including California State Parks, the National Park Service, the Monterey Bay Aquarium and Friends of the Elephant Seal.

And the film is getting play. It already showed this summer at the Monterey Bay Aquarium. After its Santa Cruz premiere it will open in San Francisco, San Simeon, Santa Barbara, Los Angeles and San Diego, and it's scheduled to screen at the Jackson Hole Wildlife Film Festival next month. To his surprise, he recently got a call from the Denver Zoo, which expressed interest in screening it.

It's been an expensive endeavor—he financed it himself—but Wharton says it's been worth it.

"You can eliminate a lot of hurdles real quick if you walk into the room and say, 'I'm going to pay for it,'" he says. "But it pays back in spades. We all get to a point in our lives when we want to do something larger than ourselves. That's why I wanted to do this."

A SEAL'S LIFE, written, directed and produced by Drew Wharton, shows Thursday, Sept. 27, at 7pm, followed by Q&A with Wharton and a lecture on elephant seal research by UCSC biologist Dan Costa, at Seymour Marine Discovery Center, Long Marine Laboratory (end of Delaware Avenue), Santa Cruz. Tickets $6 general/$4 members. For reservations call 831.459.3800.

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