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| Jean-Michel Cousteau's Ocean Adventures: The Gray Whale Obstacle Course: Essay |
The Gray Whale Obstacle Course
By Jean-Michel Cousteau
Of all the sea's creatures, none draws our attention or our affection more than those whose warm-blooded heartbeat resembles our own. These are the marine mammals, the whales and dolphins, seals and sea lions, of the waters that cover two-thirds of our planet. Considering the vast geography of their domain, it is a celebration when our paths cross far from shore and we are given a glimpse of their magnitude and mystery.
The gray whale, however, is an exception among whales.
The gray whale lives closest to us, hugging the shoreline next to a human tide of rising population, as it journeys on the longest migration of any mammal, up to 12,000 miles roundtrip. It is one of the first whales driven to near extinction by whaling and the first whale to recover and be removed from the Endangered Species list. It is the only whale that feeds directly on the ocean floor, altering its feeding grounds more than any other animal, including the elephant. It moves from the freezing waters of the Arctic to the balmy lagoons of Baja California and doesn't freeze or overheat. It goes for seven months without feeding, and then consumes a ton a day. And much of its lifestyle remains a mystery.
In 1999 and 2000, a third of the gray whale population suddenly and mysteriously disappeared. Carcasses washed onshore in unprecedented numbers and no one seemed to know why. There were many theories, but the ultimate cause may be more sinister than even the experts had imagined.
It was a reason to revisit the gray whale and to see for ourselves what obstacles lay in its course. Our goal was to witness what the gray whales were experiencing as they traveled our shores, and to learn what was threatening them in spite of all the legal protection provided over the past 80 years.
Starting where they are the most vulnerable, we began in the mating and breeding lagoons of Baja, Mexico. It was here in 1855 that Captain Charles Scammon, a Yankee whaler, discovered that gray whales congregate in large numbers to mate and give birth. He described the lagoons as so crowded with whales that you could walk across the water on their backs. He also discovered that harpooning a calf would attract the large, and more profitable, mother close enough to be taken. Protecting her calf, the forty-five-foot, 35-ton mother would do battle with the whalers, gaining a reputation for the breed as "devilfish."
Scammon's Lagoon, San Ignacio, Magdalena Bay. By 1880, these lagoons were empty of whales in a glut of hunting by the whaling industry and in only 25 years, the hunt was over because there were no more whales to take. It was here also that Scammon discovered the other life of these whales -- they migrate far to the North. Scammon found Eskimo arrowheads embedded in the flesh of whales when they were flensed and boiled down. Indigenous peoples in the northwest Pacific were also hunting the gray whale. By the turn of the century, as whales disappeared, so did a vital resource.
Nothing could be in greater contrast to the slaughter than what the Ocean Futures team found in the tranquil waters of Magdalena Bay and Scammon's Lagoon. Having been protected since the 1930s by the Mexican government, the gray whales found refuge and recovery here. Feeding on milk that is 50% fat, a calf's weight doubles here. My team arrived in a year when more calves had been counted than in any previous year, perhaps in reaction to the precipitous decline of recent years. But the contrast is as much in the behavior of the whales as in their rebounding numbers.
Our business in Magdalena Bay was placing satellite tags on whales. Our plan was to tag four mother whales as they prepared to leave the bay and to follow them the length of their migration with their calves back to the Arctic. We successfully tagged four whales without harm, but none of the tags transmitted their positions beyond a few days and a few miles north of the lagoons. Plan B was to follow the whales the hard way - consulting experts and watching from shore as we traveled the long distance north.
San Diego was the birthplace of what has become a one billion dollar whale watching industry in 90 countries. Now, over nine million people watch gray whales, humpbacks, blue whales, fin whales, dolphins, and any species that can be seen from a boat under strict whale-watching regulations. We have gone from hunting whales to needing laws to prevent us from loving them to death. Fatal collisions with ships can be a leading threat to whale survival. According to NOAA (National Oceanic and Atmospheric Administration) figures, whale-watching boats are the second known leading cause of ship strikes of whales, second only to ship strikes by the U.S. Navy.
The gray whales must navigate near some of the busiest, most populated harbors in the U.S. as they head north, passing Long Beach and Los Angeles, San Francisco and Seattle. They pass commercial shipping lanes and must circumvent enormous tankers. In addition to collisions, they are bombarded with a less visible obstacle: sound. In the last 10 years, there has been a new form of environmental pollution of the oceans -- acoustic pollution generated by different activities, from underwater explosives, to high intensity military sonar, to oil development, commercial shipping, and even intrusive scientific research. High intensity military sonar has the potential not just to interfere with behaviors or to injure marine mammals but actually to cause stranding and death. Such sonar experiments take place off the coasts the gray whales must navigate and, while federal courts have blocked the deployment of LFA, a long range, low frequency sonar, this is just one system. Militaries around the world are not only testing these powerful sonar systems but are deploying them.
Our team began to realize that in following the gray whale along its specific migration route, we were actually seeing a picture of issues that affect the global ocean.
The team also found good news. While some marine mammals are suffering from toxic contamination, gray whales seem to be relatively free of pollution. Sadly, killer whales are among the most severely polluted animals in the world, especially those who feed off the western United States. But gray whales, possibly because they feed in the relatively pristine waters of the high Arctic and because they fast for seven months of the year, seem to be little troubled by a high body burden of contaminants.
We did, however, find a dramatic link between killer whales and gray whales. In Monterey Bay, California, gray whales and their calves face their greatest natural obstacle. Once a year, pods of killer whales gather over the deep Monterey Bay canyon and listen for gray whales approaching. At the curve of the bay, the female with her calf must decide whether to follow the greater distance of the curved shore of the bay or to take a shortcut across deep water. This latter choice is usually a mistake.
In any year, a third of the calves won't survive the journey to the Arctic, for many reasons. But in Monterey, it is clear why some don't make it. In a coordinated hunt, the smaller killer whales separate the mother and calf and relentlessly attack, exhaust, and eventually drown the calf as the mother struggles to save it. One calf may feed up to 30 killer whales. Of the calves that reach Monterey, a third may be lost to killer whale attacks. Our team had the rare occasion to witness these attacks in a year when there were an unprecedented number of calves in Monterey, and so an unprecedented number of killer whales waited for their arrival.
Off the coast of Washington a few years ago, another type of hunter was waiting. In 1999, the Makah people of Washington State invoked treaty rights of 1855 that gave them the right to continue their traditional hunt of gray whales dating back to the earliest epoch of their culture. A team of Makah men in a traditional canoe harpooned and killed their first gray whale in over 70 years. Their need was explained as largely cultural, as sustenance for fading tradition and ancient pride. It was also highly controversial and vigorously protested. In 2002, a federal appeals court suspended the hunt until the impact on the local population of whales was better understood.
Farther north in Russia, the legal quota for hunting gray whales is about 135 a year. Aboriginal whaling of gray whales and other species continues in Alaska, Greenland, Russia, and the Caribbean, and it's incredibly important for many countries that don't have the luxury of being able to farm or ranch. The International Whaling Commission has recognized that these people need to hunt whales in order to survive.
But in order for a hunt to be sustainable and for quotas to be established, it's critical to know the number of whales. Our team found two land-based places along the California coast where people are dedicated to counting the whales as they migrate. South of Los Angeles, the American Cetacean Society runs a totally volunteer effort for half the year. Trained volunteers scan the horizon with binoculars and count whales. Farther north at Piedras Blancas, south of Big Sur, the National Marine Fisheries Service conducts the official annual count. Researchers here developed an ingenious technique to monitor the basic health of the gray whale population and to predict problems, much like the population decline of 1999-2000.
By mounting a camera to the underbelly of a plane, researchers found they could take accurate aerial photographs of the southbound, pregnant female whales and could identify the same whale going north with her calf. By comparing the whale's width to length over successive years, it was possible to determine if the whales were well fed, a predictor of successful recruitment of calves. In 1999 and 2000, the whales appeared thin, even going south, and emaciated on the return north. It was this year that as many as 6,000 to 8,000 whales disappeared from a population high of 26,000.
To our surprise, we also found a group of whales that don't migrate to the Arctic to feed. Off the coasts of Oregon and Washington, scientists are identifying a group of resident whales that have found an alternative source of food-tiny mysid shrimp-in quantities to sustain them. In the bad years of 1999 and 2000, these resident whales were only slightly affected and 95% of them survived.
We began to understand that the conditions of the Arctic feeding grounds are the most important factor, and sometimes the most serious obstacle, to the whales' survival.
The ominous picture is that global warming may be affecting their Arctic food source, tiny amphipods, shrimp-like creatures that thrive or fail depending on the temperature of the water. We now know that over the last three decades, global warming has added to a 30% loss in the Bering Sea of the gray whale's main food. Warmer ocean temperatures mean less food for gray whales. It now seems clear that, in spite of the many obstacles along their migration route, one-third of the whales died in 1999 and 2000 because they were starving.
With the exception of the killer whales, the obstacles we encountered in the company of gray whales were all a byproduct of human activity. If the whales are threatened, it is from death by a thousand cuts, so everything we can do to mitigate our presence in the sea will help the whales. And clearly, we must come to terms with the effects of global warming.
At the most remote part of the migration, seemingly far from any human impact, we found the whales' greatest vulnerability in the form of global warming -- possibly the greatest influence of human activity.
Standing on a frozen beach in a howling Arctic wind, we saw a gray whale surface and its heart-shaped exhalation quickly disappeared in the wind. It was clear that there is nowhere remote enough to be entirely free of human impact. The gray whale, as much as any wild animal, is forced into close contact with us as it leads its normal life. Along this voyage, we learned how close we actually are to this whale: despite the enormous gulf between us, it's still possible to find a human equivalent for virtually every bone in the gray whale's body. It is a similar, warm-blooded heart that beats in the cold sea.
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