Posted on | September 16, 2009 | 2 Comments
By Ilsa Setziol
THE DINOSAURS are gone. So too the mammoths, saber-toothed cats and short-faced bears. Even California’s mascot, the grizzly, no longer roams the state. Megalopolis has replaced megafauna. Yet the largest animal ever still graces the California coast. This summer, I went looking for it.
In Long Beach, I met up with Michelle Sousa, senior mammalogist with the Aquarium of the Pacific in Long Beach. We hopped aboard the Christopher, one of the 60-foot yachts used by the cruise operators Harbor Breeze for whale-watching tours.
Sousa and I are giddy at the prospect of seeing a blue whale. “It’s the most magnificent animal in the world,” she says. “They average 80 feet in length, but they’ve been know to get up to 108.” (That’s three times the size of the largest dinosaur.)
As the Christopher put-puts out of Rainbow Harbor, Sousa tells me that, at first, the blue whale’s size protected it from hunters. “But when they invented the pneumatic harpoon gun [it could penetrate the animal] and then explode, so people were able to kill them. And we went from a population of 350,000 to now we have less than 15,000 worldwide.”
It’s a gorgeous day. Ahead of us, ringed with mist, Catalina rises from the sea. Above us, clouds look like waves cresting in the Wedgwood-blue sky. Sousa explains that of those 15,000 blue whales, less than a third live in the northern hemisphere. Fortunately for whale-watchers, some have been feeding closer to the Los Angeles shore in recent years. “We’ve been seeing a lot more lately,” Sousa says, “we think it’s because their food is here. All of a sudden there’s a lot of krill.”
Krill are tiny shrimp-like crustaceans usually found in cold, nutrient-rich water.
Sousa is well informed, but she can’t make up for the fact that scientists don’t know all that much about blue whales. This much can be gleaned: In the northern hemisphere, grey whales are known to migrate south in winter, and back north in summer. Blues may be doing the same thing, but scientists aren’t sure; to find out, they’ve recently begun tagging the whales and tracking their movements by satellite.
The captain turns the boat north, accelerating as we swing around the Palos Verdes Peninsula. The boat slaps down on five-foot swells, tossing passengers — and sodas — around the deck, thrilling the preteens aboard and nauseating the adults. A group of bottlenose dolphins swims over to race at the boat’s bow.
Bottlenose dolphins are only one of the types of hairless, spouting marine mammals known as Cetaceans native to Southern California’s stretch of the Pacific. The bottlenecks are common, as are Risso’s and Pacific white-sided dolphins, most of them resident. Grey, finback, humpback, Minke, and Sei whales are frequent visitors. Even pods of orcas pop down to snack on sea lions.
Orcas are the wolves of the sea. “They are the only natural predator of the blue whale,” Sousa informs me. “Fifteen to 25 orcas will attack the blues in three or four strike groups.”
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THE BOAT slows. Over an intercom, Angelina Komatovich, an educator from the Aquarium, tells passengers to start scanning the pewter-blue sea for large sprays of water: “What we’re looking for is their blow. They come up to the surface and take a nice big breath. And their breath can shoot up about 20 feet high in the air. When they come up to the surface, they have water on top of their blowhole and they blow that water off.”
After about 20 minutes, someone sees a spout. We’re in luck: It’s a blue whale. The boat lurches toward it. It’s two blues!
A mother and her baby slide up to the sea surface, then arc back under. They alternate brief traveling dives with longer (six to ten-minute) feeding dives.
In krill-rich spots, hungry blues simply open their massive mouths; pleats on the underside of the jaw expand as water flows in. “They use their tongue to push all the water out,” explains Sousa, “but all the krill is caught.” For adult blues, that would be up to 8,000 pounds of krill a day.
Every day a baby blue will drink about 100 gallons of milk, gaining 200 pounds. “So every hour it’s gaining eight or nine pounds,” says Sousa.
Blues are basically solitary animals. They live in same-sex pairs or trios (excepting mom and baby boy blue). To communicate, they unleash eerie, low frequency moans that travel hundreds–even thousands–of miles across the ocean.
At a maximum volume of 188 decibels, blues trump howler monkeys for the title world’s loudest animal. Noise from busy ports and other human activities at sea, can disrupt the communication of blues and other cetaceans, interrupting breeding and feeding. “Sound under water travels so much faster, so much further than in air,” says Sousa. “It can have longer lasting effects.”
Whales are also vulnerable to being struck by large ships, which simply can’t swerve in time even if they spot the animal.
The long-term future of blues and other marine animals is uncertain. Global warming is heating the oceans and turning them more acidic. It’s hard to know how blue whales will be affected as the trend accelerates.
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THE BLUE whales are likely to stick around for another month or so. In October or November grey whales turn up en route to breeding grounds off Baja. The more abundant greys are easier to spot, allowing for a shorter, smoother ride aboard a Harbor Breeze boat.
We don’t have long with the blue whales. After three and a half hours, the boat has to return. But for a moment, with the distant city looking like a toy set, and the big blues gliding, I feel far from civilization and deep in the prehistoric past.
Copyright: Ilsa Setziol. All rights reserved.
You can learn more about marine life on the websites of the Channel Islands site of the National Marine Sanctuaries and the Aquarium of the Pacific. Aquarium visitors can get a discount on whale-watching cruises.
This post has been updated.