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There were “oysters that grow on the trees,” hanging from the trunks of mangroves which themselves offered an unlimited supply of wood. The bay swarmed with fish dubbed “mangrove-groupers;” clams and mussels fanned across the flats.
The one scarcity was fresh water. According to Scammon, you could only find it, curiously enough, by digging in the sand. “The usual process of obtaining water is to take both heads out of a cask, then place it on the beach where the water is found; work the cask down through the loose sand, and removing that on the inside of the casks, till sufficient depth is reached for the water to ooze in, and convenient for bailing. The water, when first brought on board ship, had a white or milky appearance, but after settling for a few days and pumped off, seemed quite clear and drinkable.”
Scammon noted that a few whalers had pursued Gray Whales around the bay between 1846-48, killing thirty-two. The discovery of Arctic Bowhead Whales in 1848, however, had taken many vessels far to the north. Eventually frustrated by winter storms, American whalers decided to make permanent “between seasons” cruises to Baja. They hailed from Honololu and San Francisco, as well as New Bedford, Martha’s Vineyard, and other Eastern ports. In the winter of 1855-56, they honed in on the Gray Whales at Magdalena Bay.
The whale-hunter, Scammon wrote, “now finds the object of pursuit not in the fathomless blue water, but huddled together in narrow estuaries, the banks on either hand lined with the evergreen mangrove. Frequently the hollow sound of the spouting whale is heard through the trees, and the vapor ascending is seen above them.”
Through three passages, the gray whales passed in and out of the bay’s forty-mile-long reaches. Ships anchored everywhere about various points, capes, and islands. The wooden whale boats were swift, but the Gray was a considerably faster swimmer than either the Sperm Whale or Arctic Bowhead. It also seemed to possess more intelligence. Chased through the beds of kelp just offshore, the Grays soon learned to shun these. Driven to the bay’s outer shores, they proved a ferocious prey.
Scammon would recount a tale, quoting “the king of skippers in Devil-fish lore,” a fellow whom he referred to as Captain L: “I’ll tell you what happened to me in my own boat, up in the ‘mud-hole’ [Magdalena Bay], season afore last. We was chasing a cow and calf, and I charged my boat-steerer to be careful and not touch the young sucker, for if he did, the old whale would knock us into chopsticks; but no sooner said than done – slam went two irons into the critter, chock to the hitches, and that calf was ‘pow-mucky’ in less than no time, and the boat-steerer sung out: ‘Cap’n, I’ve killed the calf, and the old cow is after us.’ Well, just about this time, I sung out to the men to pull for the shore as they loved their lives; and when that boat struck the beach, we scattered. I’ll admit I never stopped to look round; but the boat-steerer yelled out: ‘Cap’n, the old whale is after us still,’ when I told all hands to climb trees!”
Most of Captain L’s crew became so discouraged that they went off on a fruitless expedition into the mountains in search of Baja gold. But if the tree-climbing tale was perhaps apocryphal, what Scammon witnessed in Magdalena Bay in the winter of 1856 was very real indeed. Sixteen Gray Whales were set upon one morning, the men rowing into harpoon range in wooden boats no more than thirty feet long and six feet wide. The whales destroyed two boats entirely and staved the others fifteen times. Six of eighteen crew members were hurt: one came away with two broken legs, another with three fractured ribs. All before a single whale was captured.
In a report for the U.S. Fish Commission, Charles H. Townsend described cruising along this coast in search of sea elephants in 1884. “I heard many stories told by the natives of the ferocity of the female gray whales when attacked in their breeding places – stories amply attested by the number of graves of ill-fated whalers one meets with all along these desolate shores….That fatalities were of frequent occurrence may be emphasized by the statement that in the vicinity of the now deserted lagoons a leading feature in the landscape is the solitary grave with its conspicuous fence of weather-worn whale-ribs.”
Long afterwards, a trading vessel docked at one of the bay’s two large islands in 1914. The Mary Dodge was primarily looking to buy guano for use as fertilizer, but the captain told the local people he’d also pay ten pesos a ton for whale bones. They went to work collecting. The Mary Dodge left with 125 tons, promising to return for more in a few months. A massive additional pile, 200 tons of Gray Whale bones, was gathered on the beach. The ship never came back. The bones remained, a kind of monument to the carnage that had occurred there.
Between 1845 and 1874, American and European whalers had killed an estimated 3,290 gray whales in the lagoons and bays of Baja. More than half of these – some 2,100 – were taken in Magdalena Bay. Scammon reported that the five-year period between 1856 and 1861 was the most lucrative for whalers in the bay, with 34,425 barrels of oil at fifteen dollars a barrel bringing in $516,375. Fifty whaling ships anchored there in the winter of 1858. Nine years later, when Scammon’s friend J. Ross Browne traveled to Magdalena, there were only two. Gray whales, Browne wrote, were “becoming scarce, so much, indeed, as to render their pursuit no longer profitable.” Scammon added, “where thousands of barrels of oil were taken annually, now only a few hundred are obtained.”
[SPACE]
It took a full day for me to drive from San Ignacio Lagoon south to the deep-water fishing port of San Carlos on Magdalena Bay. Along the last stretch through the Santo Domingo Valley, irrigated fields of corn and alfalfa blend with orange trees, amid jumping choya and cardón cactuses where Mexican eagles perch. On the outskirts of the town, I found myself passing alongside a sprawling industrial complex. This is Termoelectrica C.F.E., a new power plant designed to balance more than half the electrical grid of the Baja peninsula, from Guerrero Negro down to Cabo San Lucas. It was built, in a joint venture with the Mexican government, by none other than Mitsubishi Heavy Industries. While the plant is advertised as thermoelectric, it’s really diesel-fueled. A restaurant in San Carlos was built out of the heavy-duty timbers used as crating material for shipping it here. The engine is three stories high. It’s a 45,000-horsepower, 12-cylinder in-line motor, and it churns a generator that’s 30 feet in diameter.
The Japanese are rumored to be biding time on erecting a resort complex south of Magdalena Bay – a couple of hotels, a golf course, a marina, aquaculture farms for shrimp and oysters. They’re said to have bought the land, but run into that basic problem Scammon wrote about: a dearth of water. Today, water for the 4,000-some residents of San Carlos is pumped from a large well about twenty miles inland on the Magdalena Plain.
At the edge of town, where pavement turns abruptly to sand, vendors at little roadside stands waved their arms and did their best to flag me down. They were peddling whale watch tours. Each February since 1994, San Carlos and Puerto Adolfo López Mateos – another bayside town eighty miles to the north – have held festivals celebrating the birth of their ballenas – complete with concerts, fireworks, and Miss Gray Whale beauty pageants. With an estimated 12,000 foreign tourists showing up each winter season, whale watching has become big business on Magdalena Bay.
Instinctively, I was uncomfortable. My first encounter with a local guide came in a restaurant, where the fellow was hustling several Americans at the next table, bragging about how he’d twice actually hopped on a whale’s back and been taken for a short ride. Later, I’d hear that this same boat driver had recently rammed into a whale. A local whalewatchers’ union of between forty and fifty skiffs had been formed. On weekends, twenty-four whale-watching pangas at a time were allowed out on the waters here. An American hotel owner told me he’d seen as many as fifteen people crowded into a single boat. Oftentimes, whales got chased and he said it was amazing there weren’t more accidents.
It was suggested I seek out Francisco Ollervides, whom everyone calls Paco. He was Mexican, and working on a doctoral thesis for Texas A&M University. For the last three years, he’d been coming to San Carlos trying to get a better handle on how whale watching affects the Gray Whales. Specifically, Paco was analyzing how the whales move and behave around boats. Also, did they respond differently to the engine noise emanating from tourist-laden pangas than they would to a shrimp trawler or one of the oil tankers bringing fuel for the power plant?
I found Paco Ollervides at his wintertime base, the School for Field Studies, a complex of palm-tree-shaded buildings right on the bay. Headquartered in Beverly, Massachusetts, the School for Field Studies can be found in half-a-dozen locations around the globe, including Kenya, Australia, Costa Rica, and here in San Carlos. The students, primarily Americans, spend six months in small communities working on environmental problem-solving. In San Carlos, they were involved in helping the fish cannery do something about its effluent discharge, and in studying the impacts of ecotourism on the gray whale population.
“This bay is different than Guerrero Negro and San Ignacio,” Paco explained, “because it’s the only area the whales come to which is not part of the Biosphere Reserve. That was why I was interested to observe in Magdalena Bay, since it does not have the same protected status. It has the same whale watching regulations, but different pressures. There’s a bigger surface area and less enforcement. Boat captains do a lot of violations of the regulations, and this goes unchecked. With the Mexican authorities, we’re trying to design some core areas where whale watching should not occur.”
At nine the next morning, I met Paco and his assistant, a graduate student from the University of Kansas named Jennifer Pettis, at the gated entry to the port of San Carlos. This is Baja’s only deepwater port besides Ensenada, and vessels of all shapes and sizes are moored at the pier. A fishing trawler has just tossed a huge shark onto the dock. Paco, who’s in his early twenties, is dressed in shorts and wearing an Australian bush hat. He beckons me to follow them up about a hundred feet of metal stairs to an observation tower. 1999 is an unusual year, in that not only are more whales occupying this southernmost sector of the bay – some three hundred compared to a maximum count of sixty-six in ’98 – but many are also opting to stay in the vicinity of the port. “Generally they prefer to be at the mouth,” Paco says, “which is about an hour away from here. So this year has been incredible for the whale watching companies – and for us.” As we reach the enclosed tower, Paco points out several large vessels winding down the bay’s shipping channel through dunes and mangroves, past one of the longest islands in Mexico. “The whales have been seen to avoid areas like San Francisco or L.A., which could be a result of ship traffic,” he adds. “It could happen here, too – if it goes unregulated and the number of boats just increases every year.”
The view from up here is spectacular. I gaze into the near distance at a complex of inland tidal channels protected from the Pacific’s rollers by misty volcanic peaks and the dunes of Magdalena and Margarita islands. The spouting of gray whales just below me looks like smoke signals wafting up. “Right now it’s good sea conditions because the wind is not blowing,” Paco says. “Otherwise the blows get taken away really fast.”
He commences adjusting the angles on a surveyor’s theodolite. This method of monitoring whale movements was pioneered by Roger Payne. A theodolite is basically a transit – the same kind you see obtaining level measurements along a road – which measures the azimuth and downward angle. The bubbles inside it, Paco says, tell you how balanced the theodolite is. Jennifer records all the data onto a computer for later analysis.
Paco zeroes in on something, and motions me to take a look. It’s a jarring close-up: a dead Gray Whale, floating belly-up, its body adorned with seagulls. “We think it’s the same one we’ve been seeing for a couple of days,” Paco says, “it just moves up and down with the tide. We’ve even see one right down here in front of the pier.” Six of the seven dead Gray Whales documented here this year have been females. Paco has been plotting the exact locations on a map. On the one that washed up by the dock, he conducted a necropsy to try to determine the cause of death. The inner earbones were extracted and sent to an expert with Massachusetts’ Woods Hole Oceanographic Institution and the Harvard Medical School laboratory where, Paco continues, “they will do CT scans and MRI’s to see if there’s been sound damage that might have caused the whale to die.”
We would do well at this point to consider the remarkable auditory sensibilities of the Gray Whale and its brethren. Scammon observed: “The ear, which appears externally like a mere slit in the skin, two and one-half inches in length, is about eighteen inches behind the eye, and a little above it.” In the human brain, the centers for sight and hearing are approximately the same size. In the brains of whales, however, the sensory nerves responsible for hearing are much larger than those for seeing. It’s a matter of environment. Beneath the ocean’s surface, darkness and turbidity impose extreme limitations upon sight. Sound, however, not only travels farther underwater than in air, sometimes for thousands of miles; sound also travels four-and-one-half times faster than in air, at speeds of up to 5,000 feet per second. Within the inner ear of the Gray Whale as well as other cetaceans, features have evolved that are capable of picking up a spectrum of sounds which are inaudible to people. At the same time, as Aristotle put it long ago, “Even a small noise…sounds very heavy and enormous to anything which can hear underwater.”
In what may be the earliest consideration of the Gray Whale’s sensitivity to noise in its environment, the Monterey Sentinel had this to say in the spring of 1856 about the whalers’ latest advance in weaponry, the bomb lance gun, whose load of powder exploded on impact: “….the whales are every year getting more shy from the use of the bomb lance. It is said that they hear the bomb explode in the water, even though ten or twenty miles off.”
In his description of whaling on Magdalena Bay, Scammon offers additional insights: “Every ship’s cooper and his gang were busily at work with their heavy hammers, driving the hoops on the casks, and the whole combined produced a deafening noise upon the water, which echoed from cliff to crag along the mountain island of Margarita. This, with the chase and capture of the animals, the staving of boats, and the smoke and blaze from try-works by night, soon drove the whales to the outside shores.” The ship’s captains talked over the situation, and many decided to go look for whales elsewhere. “After suspending whaling for a few days, and a number of ships leaving meanwhile, the [gray] whales again returned to their favorite haunt.”
There is evidence that ship traffic may have directed the gray whales away from another nursery area, the warm waters of San Diego Bay. A 1922 History of California Shore Whaling records: “Smythe’s History of San Diego states that in the early forties [1840s] San Diego Bay was a favorite place for the female whales in the calving season, and at such times on any bright day, scores of them could be seen spouting.”
Dr. Marilyn Dahlheim, who today works out of the National Marine Mammal Laboratory in Seattle, was one of the first to scientifically point out that sounds – both natural and man-made – could have a dramatic impact upon Gray Whales. She spent five winter seasons at San Ignacio Lagoon, 1981-85, researching a dissertation for the University of British Columbia titled “Bio-Acoustics of the Gray Whale.” Off the narrowest sector of the lagoon at Rocky Point, she submerged a cage that housed a little transducer which could broadcast different types of sounds underwater in the direction of the whales. When outboard engine noise was played, Dahlheim was fascinated to find the whales attracted to the transducer. When she went up to the middle lagoon area, where sound transmission was reduced because of the extensive sandbars, she discovered something equally intriguing. “I’d heard about whales hiding behind islands or icebergs to avoid increased levels of sound in their environment, but I never knew whether to believe it,” Dahlheim says. “But when I played oil-drilling sounds, not even at a very high decibel level, I found clusters of whales in the middle lagoon behind those sandbars, where there are what I call ‘sound shadows’ and the noise wasn’t as intense.”
After spending her first two years profiling the whales’ acoustical habitat and characterizing their types of calls, in 1983 Dahlheim started conducting short-term playbacks. The next year, she increased the duration of the playbacks. Her goal was to determine how Gray Whales might alter their own sound structure when faced with longer-term and increased levels of man-made noise. She played 120 hours of pre-recorded sounds ranging from industrial noise to the vocalizations of the Gray Whale’s primary predator, the Killer Whale. What happened was very telling. When faced with increased levels of noise, the mothers and calves took their leave early. By the beginning of March, their count in the lagoon was 81% lower than the mean count of 223 whales for the five-year period between 1977 and 1982.
Looking back on her reaction, Dahlheim says: “At first I didn’t quite believe what was happening, that my little transducer was causing this. I remember some of my team members sitting around the camp at night discussing it, saying ‘oh my God, what’s going on?’ As a group we thought, well, we’ve got to continue, because if what we’re seeing is a response to these types and levels of noise, we need to know – and we don’t want to do it again.”
Because of this striking effect upon the whales, the Marine Mammal Commission funded a follow-up study in 1985. This time, no artificial sound projection took place. Dahlheim was strictly looking at the numbers and distribution of whales in the lagoon. The Grays’ numbers were back up, though not as high as they’d been during the previous several years.
Now Paco Ollervides has been able to establish some very “significant correlations” between numbers of boats and behavioral reactions of whales in a given area. In the presence of larger vessels in Magdalena Bay, Gray Whales were seen to change their swimming speed and direction, as well as their breathing intervals. In general, groups of half-a-dozen would congregate in the mornings when there was no ship traffic. With the arrival of boats, the whales would disperse into pairs or singles, coming together again after the boats departed.
What Paco is observing is, of course, taking place within a relatively confined space. In a broader ocean context, Dr. Christopher Clark, of Cornell University’s Bioacoustics Research Program, has described what marine mammals face today as an “acoustics traffic jam.” The noisiest offenders are supertankers and cargo ships, whose propellers emit a pervasive low-frequency hiss which penetrates more deeply in warmer water. The shipping lanes pretty much parallel the Gray Whale’s migratory route. Along the central California coast alone, more than 4,000 large vessels transit annually. Baleen whales such as the Gray are presumed to hear – and to vocalize – in the same ranges occupied by ship noise. Might the din be causing potential hearing loss? Or drowning out vital communication, say for a Humpback Whale calling to a prospective mate several hundred miles away?
“In terms of behavioral disruption, shipping is what I’m most concerned about,” says Dr. Peter Tyack, a senior scientist with the Woods Hole Oceanographic Institution and an expert in whale acoustics. “In terms of potential for ear injury, it’s the most intense sound sources, such as explosions, sonars, and the air guns used for seismic surveys by the oil companies. I don’t know whether there’s been an explicit cozy agreement between the oil and commercial shipping industries with the regulators, but it’s certainly been a policy of ‘don’t tell us, we won’t look or ask questions.’ It’s very important there be a strong push to recognize the real risks to marine mammals and come up with a reasonable policy that covers and regulates all these sources of noise.”
During the 1990s, several new sources of oceanic “noise pollution” came on-line and under fire. One was the deployment of acoustic deterrence devices by commercial fishermen looking to drive away seals from their catch, with only minimal guidance from wildlife agencies. Another was an experiment in acoustic thermometry, where the Scripps Institution of Oceanography embarked on a $40-million effort using underwater loudspeakers to boom high-intensity (195-decibels), low-frequency sound waves across expanses of ocean. The aim was getting a better handle on long-term climate change, by measuring the speed of sound to “take the temperature” of the sea (the warmer the water, the faster sound travels). Several studies of potential impacts to whales and other sea denizens were carried out, to inconclusive results, and the project has foundered.
Gray Whales became the centerpiece of research focusing around the third – and most controversial – recent deployment: the Navy’s Low Frequency Active (LFA) acoustic sonar system. The Navy would like to deploy this across 80% of the world’s oceans. Designed to detect enemy submarines by scanning the seas with soundwaves, LFA would flood thousands of square miles of ocean at a time with intense sound. After a dozen Cuvier beaked whales beached themselves in 1996 during NATO anti-submarine exercises in the Ionian Sea, and faced with a potential lawsuit from the NRDC, the Navy set about undertaking an environmental review of how LFA sonar might affect marine mammals.
That’s where Peter Tyack came into the picture. As part of a three-phase study commissioned by the Navy, in January 1998 he and a colleague conducted playback experiments in low frequency sound to probe the behavioral responses of Gray Whales migrating off the central California coast. I’d met with him some months later to discuss his findings. Tyack is a slightly rotund, blond-haired, white-bearded fellow with soft blue eyes and a pleasant demeanor. He did his thesis on the songs of humpback whales, and has been studying how whales and dolphins “use communication signals in the context of their social behavior” since coming to Woods Hole in 1982. He’d been part of a team in the 1980s that performed similar playbacks of oil industry sounds at migrating Gray Whales. These included air guns used in seismic explorations. The biologists had concluded from this study that the whales were more sensitive to continuous noise – they’d tend to avoid exposure at levels of around 120 decibels – than they were to the short pulses of the air guns. Dissenting scientists claimed the whales didn’t really care about loudness one way or another.
So Tyack hoped that his tests for the Navy would provide some more definitive answers. “If Gray Whales showed an avoidance response,” Tyack said, “my main concern was that this Navy sonar could impact other animals over huge areas in the open ocean if the ship were operating in the middle of the North Pacific or North Atlantic. That’s because low frequency sound can propagate over a very big range.”
Migrating Gray Whales made an ideal case study, because hundreds a day were sojourning close to the coastline, “and you know it’s always new animals, since nobody’s circling back around north.” They could also be watched from shore, instead of from a boat or airplane that might already be disturbing their behavior, by using a theodolite to pinpoint their location. As they moved past, the whales’ path was plotted by computer. Meantime, a sound source was placed on a ship moored in the center of the migration corridor. Its underwater speaker blared sound at the whales at varying decibel levels, of forty-two seconds duration and repeating every six minutes. The question was, would the whales noticeably change their course and at what range of noise?
The procedure is more complex than I’m outlining, replete with scientific controls and assorted attenuated simulations of stimuli. Suffice that the experiments as designed were highly sensitive, and were conducted over 150 hours during 18 days that yielded tracks on about 1,400 whales. I sat next to Tyack at his computer as he ran through his data accompanied by a few low-frequency imitations of the sonar sound – a higher-pitched “ooo ooooo ooooo….” and “whoooooooo….” followed by a deeper, slower “whoooo whooo whooo.”
The hypothesis, Tyack said, was “that the behavior of the whales would be disrupted and they’d avoid exposure at received levels in the range from 120 to 155 decibels.” Whales avoided these sound levels in previous studies, even though these levels are not very loud by the standards of human noise in the ocean. The source level of a small outboard, for example, is 155 decibel levels at one meter; the boat would have to be a hundred yards away to reach the lower end of this exposure range. In this latest test, the whales did move away from the sonar sound imitations – but not significantly. They only skirted the sounds by about one hundred meters. Even with a source level of 170 decibels, according to Tyack, “they were a little less sensitive to the LFA sonar than we’d expected.”
He clicked his computer mouse to another diagram. “But here,” Tyack continued, “comes the big difference.” When the sound source level was increased by another fifteen decibels, the whales suddenly avoided the noise by a full kilometer. They swerved upstream away from the sound, an avoidance reaction so dramatic that “blind” onshore observers (who didn’t know whether a playback was happening or a control) could instantly ascertain what was transpiring. “See that giant gap on the screen?” Tyack asked excitedly. “That’s a huge difference in the scale of response. That’s saying the whales sure as hell do care about how loud the sound is, and they’re choosing to move big-time to get to a lower exposure. All the critics of our earlier work would have claimed there won’t be any discernible difference. So this was totally satisfying. Almost never in whale science do you have a couple of days when you can resolve a question like that.”
Then the scientists decided on one more test. They kept the same 185-decibel sound level, but they had their ship move twice as far offshore, “away from the center of the migration corridor, but a place where there are still some whales.” What happened when the sound was turned on again, Tyack recalled, was a complete surprise. He recalled: “Many whales passed near the source, but they paid no attention to the transmission. We even raised it to a 200-decibel playback, and still the whales had no problem with it whatsoever.”
Tyack took a deep sigh. “Well, every experiment that works usually opens up some whole new can of worms. I don’t know what exactly is happening here. My hunch is, it relates to the behavioral ecology of what the animals are doing. For certain reasons, Gray Whales stick right next to the coast as they’re migrating. So I wonder if they’re listening to surf, or using some acoustic cue in the near-shore areas for migration. And maybe putting a loud noise right near that interferes with the process of orientation in migration – in a way that an offshore sound source doesn’t do. We’ll have to learn more about the sensory basis of migrations to really get at that.”
The scientists’ conclusion? The Navy’s LFA Sonar should be kept away from inshore migratory corridors and near-shore areas in general. The Navy’s response was to limit the operation of the system to more than twelve nautical miles from shore. “That’s a bit of a safety zone from my perspective,” Tyack said, but he cautions that much more needs to be learned.
Other marine biologists are not as sanguine. Another researcher of whale acoustics, Dr. Lindy Weilgart of Dalhousie University in Halifax, Nova Scotia, points out that Tyack’s tests used only a fraction of the full operational power level of the Navy’s LFA system. “Tyack may well be right,” Weilgart says, “but it would be safer to assume that if inshore whales are clearly shown to avoid LFAs, then the problem may not just be with using LFA in that particular environment, but everywhere. Perhaps the offshore migrating whales – those that reacted less – were already more damaged or marginal individuals. Anything that has the potential to change, even slightly, a whole population of migrating whales should be viewed with great caution. If something serious befalls these migrating animals, it means that the whole population is doomed.”
For his part, Tyack is most concerned about deep-ocean, deep-diving toothed whales such as the sperm and beaked whales, in areas where sound refracts downwards and animals could face jeopardy when foraging in the depths where the LFA energy concentrates. Tyack told me: “There continue to be anecdotes of military sonar activities associated with beaked whale strandings. The fact that they dive deep, are globally distributed, and we know so little about their behavior makes me at least want to find out – what really happens when a sperm or beaked whale hears a sound of 140 decibels? Does it stop its normal feeding? Does it show avoidance even if the source is a long way away?”
Later, in mid-March 2000, more answers came about Navy acoustics – and the results were tragic. Shortly after the Navy began conducting sonar tests in the Bahamas, seventeen whales from four species beached themselves on the islands over a four-day period. Seven died, and two had bleeding eyes which suggested acute shock trauma. Despite the Navy’s initial conclusion that its testing and the strandings were coincidental, a study by the National Marine Fisheries Service found the whales had suffered hemorrhages of varying degree in or around the ears possibly caused by “a distant explosion or an intense acoustic event.” Late in May, the Navy cancelled another test scheduled off the east coast of the U.S. and announced “a priority need” to examine the LFA issue.
[SPACE]
The question of what drives whales either toward us or away from us, of what they hear as we beam or approach them with our mechanical toys, leads to another question: the means by which whales might “talk” to one another about the various situations they face. We know that all whales “speak” acoustically, but how they do so is still largely a mystery. They produce sound by squeezing air through either their larynx or their blowholes, or by way of bursts of air from their lungs. Humpback Whales, as Paco Ollervides puts it, “sound like violins,” and are known for inventing complicated songs that sometimes continue for more than an hour. Killer whales, or orcas, make high-pitched sounds at frequencies as high as 24,000 Hz. By contrast, humans generally speak in a range between 2,000 and 4,000 Hz. Gray Whales have a wider range of communication than people, and also span the same frequencies we talk in.
In the 1850s, whalers were the first to report Gray Whales making audible sounds that could be heard above water. H.L. Aldrich wrote in 1889, “It has been known for a long time that humpback whales, blackfish, devilfish [gray whales] and other species of whales sing.” Yet when marine scientist Carl Hubbs tried listening through a hydrophone to Gray Whales at the San Ignacio Lagoon in 1950, he couldn’t detect any signals at all. “All we picked up was the chatter of shrimps,” Hubbs reported, in one newspaper article headlined “Sea Sleuths, Underwater Wire Tap Fails in Efforts to Make Whales Talk.” Hubbs wondered if Gray Whales might, like giraffes, be voiceless.
So at that point, Gray Whales were labeled “the quiet whale.” Then, in 1955, what appeared to be pulses from a Gray Whale were recorded off Point Loma near San Diego. A small landing craft was maneuvered purposefully into an oncoming whale’s path, then its engines shut down. To avoid collision, the whale changed course slightly and emitted a series of sounds. Two years later, Soviet whalers in the Bering and Chukchi Seas reported hearing “low pitched roars” coming from Gray Whales.
The 1960s saw the first breakthroughs in cracking the Gray Whales’ sound barrier. Some of the most extensive early research was conducted by the Anti-submarine Warfare and Ocean Systems division of the Lockheed-California Company. They wanted to gather data on Gray Whales “because of their obvious antisubmarine warfare importance as potential ‘false targets’ for passive and active sonar.” An expedition was mounted to Scammon’s Lagoon. While it was established that individual Gray Whale pulses lasted about one-tenth of a second and usually occurred in groups of four to six, as faint whisting sounds or “croaker-like grunts” and “low-frequency ‘rumbles,'” excessive ambient background noise made by snapping shrimp in the shallow lagoon waters continued to make underwater listening difficult. Follow-up studies detected intense sounds which scientists likened to hammering against the hull of a wooden ship; crunching and scratching noises; metallic “blip blips” like coffee percolating, and defined cries from a juvenile Gray Whale in the course of capturing and transporting the animal from Scammon’s Lagoon to a research tank at Sea World.
Then, in 1967, came a report by the Office of Naval Research and the University of Rhode Island titled “The Controversial Production of Sound by the California Gray Whale.” Hydrophones lowered into the water off Point Loma and La Jolla in southern California discovered the migrating whales to be continuously vocal over thirteen days and nights. The researchers had decided to try to force a highly controversial issue. There had been many recordings of toothed whales using echolocating sonar, but very few reported instances of baleen whales doing so. So the scientists met the southbound whales head-on from a 70-foot-long Navy transport vessel. The wake of the ship’s propeller, along with an adjacent kelp bed, created underwater visual and acoustic interference around and through which the whales had to maneuver. The closer the whales came, the louder a series of “notes” could be heard, “like those from a comb as one runs a thumbnail down the fine teeth.” The elicited sounds were under 2,000 Hz, and thus would normally go undetected or be passed off as other unidentified noise. But the researchers were now convinced that the Gray Whale “does produce trains of pulse sounds similar to the echolocation bursts of toothed cetaceans,” on an as-needed basis. One Navy Electronics Laboratory oceanographer described the whales making a deep moaning “like the left hand sounds of a piano,” and suggested these low noises might cause echoes enabling the whales to detect large objects – not only ships, but land masses or other whales.
By the late 1960s, scientists analyzing some 18,000 meters of recording tape concluded that Gray Whales were not quiet at all, but in fact are among the most vocal of allwhales. Researchers at Scammon’s Lagoon noted that it wasn’t uncommon for Gray Whales to make a series of clicking noises when a plane or helicopter passed close overhead. Gigi, a young Gray Whale held in captivity for two years during the early 1970s, was also heard to make rapid clicks when she was released back into the wild – a sound she’d never uttered while being studied at Sea World. Were these clicks indications of anger? Excitement? Fear? Attempts to communicate with other migrating whales?
Marine biologist Steven Swartz later had this to say about his six-year-long observations at San Ignacio Lagoon (1978-84): “If a female wants to recall her calf from a group of calves, or if she’s sleeping and decides to leave, she utters some sort of sound. The calf responds immediately and off they go. So there’s definitely communication going on amongst them. Exactly how it’s carried out and what’s the significance under various circumstances I don’t know. No one’s done the definitive work on the gray whale’s song, if you will, or on gray whale dialects.”
Swartz noticed the whales would habitually approach his boat from the rear – the first indication, he says, “that something about the engine sound interested them or was providing a beacon for them to orient on. Then they’d flip over upside-down and look at us. For awhile, that was puzzling. We put on our masks and stuck our heads in the water and watched them.” Similarly to what Roger Payne conjectured about the grays’ spy-hopping in the proximity of boats, Swartz soon realized that the whales were checking them out in a rare moment of having to look up.
Swartz and co-researcher Jones elaborated in a jointly written study: “They appear to show an interest in the submerged portion of the outboard engine running in neutral, such as the nonrevolving propeller and exhaust ports from which sound emanates. Some whales repeatedly bumped the still propeller of the engine with their rostrum and even took it into their open mouth. The whales avoided Mexican fishing boats with 40-hp engines running at high speed. However, they approached and even followed 20-hp engines running at moderate or low speed. Curious whales usually left the vicinity of idling outboard engines when they were shut down, and they also avoided nonmotorized vessels including kayaks, canoes, and small sail boats.”
In one “experiment,” Swartz said, “We could actually get them to trumpet blow, like a humpback, by revving the outboard engine. They expel bubbles underwater and there’s quite a bit of sound associated with those big bubble bursts. They’d blast, we’d rev the engine, and they’d blast again. We’d get this kind of rapport going back and forth.”
Shari Bondy, another longtime gray whale observer who resides in Guerrero Negro, made some related observations in a paper titled “Behavioral Changes in Gray Whale Population in Ojo De Liebre [Scammon’s Lagoon].” Gray Whales, she wrote, “can react evasively to small changes, like alterations in speed or direction of a boat or a switch of captains or motors of a particular panga. For example in 1997, the Ejido Benito Juarez replaced the old motors they had used for years with new Yamaha engines on all three pangas. Almost all whales were very evasive and even dove deeply, throwing their tail (which is very unusual there). It took a full week for the whales to become accustomed to the new sounds of the motors and gain enough confidence to allow the boats to approach again.”
At San Ignacio Lagoon in 1999, John Spencer had also talked with me about the whales and the boat motor. “It’s amazed me for twenty years,” he said one night around the campfire, “how can animals this big not bump the boat more? Not that they’d be aggressive, but just their size. You stop to think about it, they’re water acrobats. When a forty-five foot animal can rub his nose on one side and his tail on the other side without bumping you, you’ve gotta figure they know where they’re at in the water. What I think the motor does, along with telling the whales where we’re at, is to give them a sense of direction about the size of the boat. And how they can play with it. And with us.”
It was researcher Marilyn Dahlheim who first found it “noteworthy that these ‘curious’ whales respond to underwater engine noise that occupies the same frequency ranges as their own signals.” However, Peter Tyack shares John Spencer’s view that’s not all the “friendly” gray whales are responding to. “I wouldn’t think that just an overlap of frequency range would necessarily make something attractive,” Tyack told me. “It certainly would make it easier for the whales to detect the boats. But what’s amazing is simply how social and interactive these animals are. The fact that they’re willing to reach out toward our species is a remarkable thing.”
Tyack also takes issue with scientists who assert that, because what we hear of Gray Whale “communication” consists primarily of grunts and pops and clicks, these whales are necessarily more “primitive” than, say, the Humpbacks. “I think it’s very dangerous to assume that if you hear what sounds like a simple acoustic repertoire, that means the communication system is primitive or very simple. Humpbacks produce their song in an ecological setting where sexual selection has caused there to be a strong pressure for that song to be very complex.”
Then there are Sperm Whales which, Tyack notes, “basically just make simple clicks, but in different rhythmic patterns. Some appear to be individually distinctive, others group distinctive, and still others are shared over a broad geographical area. These simple clicks solve very complex problems in amazing ways, so it would be a grave error to say, ‘Oh well, they just make clicks.'” Jim Nollman, an author and founder of Interspecies Communication, Inc., told me he believes the Sperm Whales’ clicking to one another constitutes “some kind of a symbolic language, based on echolocation. At the least it’s sending holograms to one another. I believe one Sperm Whale can turn to another and show a 3-D movie of what it just did in a deep dive, actually display the giant squid it just ate. This kind of communication is not based in grammar, but in physics.”
Gray Whale communication – and what’s been misinterpreted as their muteness – may in part be a means of avoiding detection by their inshore enemies. In terms of man, Charles H. Townsend described in his 1886 report for the U.S. Fish Commission how so many Gray Whales had been wounded by inexperienced hunters using the bomb-lance gun that the whales “became wary and in general more quiet in their movements, leading some of the whalers to a suspicion even of their ‘blowing’ more cautiously.” Another report, published by naturalist Roy Chapman Andrews in 1914, recounts the story of a whaling captain “hunting a Gray Whale in a perfectly smooth sea. The whale had been down for fifteen minutes when suddenly a slight sound was heard near the ship and a thin cloud of vapor was seen floating upward from a patch of ripples which might have been made by a duck leaving the surface. The whale had exposed only the blowholes, spouted, refilled the lungs and again sunk, doing it almost noiselessly. The gunners assert that this is quite a usual occurrence when a single Gray Whale is being hunted.” (Steven Swartz would later term this “snorkeling behavior,” a phenomenon exhibited by no other species of whale. Because the grays’ twin blowholes – actually nostrils that connect directly to the lungs – are directly above the eyes and so high up on their heads, this enables them to breathe while barely breaking the surface.)
A no less compelling example of the grays’ reaction to a predator focuses around the orca, or killer whale. Two researchers for the Naval Undersea Research and Development Center conducted an experiment in the late 1960s, subjecting Gray Whales migrating south to three different sound sources: Killer Whale “screams,” a pure tone of the same frequency, and loud random noise. They didn’t react to the latter two, but fully 95% of the time, “Blowing whales, or those running at the surface, immediately swirled around and headed directly away from the killer whale sound source.” Hiding close to inshore kelp beds, “in many instances their blows were invisible and even blows at close range were scarcely audible.”
Peter Tyack finds it striking just how reactive Gray Whales are to the playbacks of Killer Whales. “I’d expect that, when they’re migrating and very concerned about being detected by an acoustic predator, that may put a lot of constraints on the Gray Whales’ communication signals. That doesn’t mean the signals aren’t important. Within a small group, they could very likely be making a set of faint contact calls. When we scientists hear the sounds, these are very much like ambient noise. A lot harder for us to study, and less flashy. But flashy doesn’t always mean inherently complex. It’s not like the Gray Whales are being silent. My hunch is, they’re just being cryptic. I’d call Gray Whales exquisitely acoustic animals.”
Marilyn Dahlheim’s experiment at San Ignacio Lagoon found Gray Whales would cease vocalizing altogether and do snorkeling behavior in the presence of Killer Whale sounds. She taped Gray Whales for more than two hundred hours at the lagoon, using a hydrophone off a small Zodiac. Dahlheim’s overall analysis not only found the Grays “more soniferous than expected from published accounts.” One of the sounds she detected – akin to the ringing of a Chinese gong – has never been heard outside the lagoon. Altogether Dahlheim was able to define seven distinct sounds and identify numerous situations in which Gray Whales are the most vocal. These included when they were in a small area or interacting with bottlenose dolphins; on a collision course with a boat or another whale; when single whales were chasing mother-and-calf pairs, and when boat noise was prevalent.
Dahlheim noted that Gray Whale signals were consistently produced below biological ambient noise, down beneath the constant clatter of the lagoon’s snapping shrimp and where it’s relatively quiet. In the case of the whistling calls of Bottlenose dolphins, it was just the opposite. Their signals hit the “ceiling” of the snapping shrimp, and bounced back up. “These data imply,” Dahlheim wrote, “that these cetaceans have different acoustical ‘niches’ possibly dictated by the constant high levels of biological ambient noise in Laguna San Ignacio.”
The “acoustical niche” idea represents an adaptable strategy that would ensure an animal minimum interference with its own signals. The peak of Gray Whale sound production occurs in the Baja lagoons. Studies haven’t shown the whales to be very vocal along the migration. In doing acoustics work off Alaska’s St. Lawrence Island, Dahlheim found the Grays make almost no sound whatsoever on their Bering Sea feeding ground. Unlike the dynamic acoustical habitat within the lagoons, she points out, there aren’t a lot of fish making noise in the whale’s northern territory. The natural ambient level is very low, too, consisting of little more than sea noise and rain.
Dahlheim believes the types of calls that whales make have evolved over time to reduce competition with the natural acoustic levels in their environments. They can be exposed to such sounds at high levels – rain, for example, can be heard down to depths of 2,000 feet. Dahlheim compares this to terrestrial situations, for instance where monkeys in the Madagascar forests utilize whistle calls to cut through the dense vegetation.
All of which implies, of course, that anything that reduces a whale’s receiving-and-transmitting capabilities could adversely impact their reproductive potential or even their survival.
In certain ways, Paco Ollervides is picking up where Marilyn Dahlheim’s work left off with Gray Whales (she’s now into her second decade studying Killer Whales in southeastern Alaska). Besides Paco’s theodolite tracking to observe the interactions between whales and boats, he’s looking to discern whether the whales change their vocalizations to suit different situations. To do this, several days a week Paco goes out into Magdalena Bay in a panga, with a portable hydrophone. The engine is turned off, and the hydrophone is placed underwater at predetermined stations. Paco records what it picks up for five minutes at each site.
Paco explains: “From Marilyn Dahlheim’s work, we have the known signals of Gray Whales and a basis for how gray whale sounds change in the presence of increased noise. We’re trying to see if, when there’s boat noise, they do any changes in the initial frequency or the duration of the call or eliminate some calls. It’s a little hard, because the sound frequency of the boats is very similar to the sounds of the whales. There’s this phenomena called masking, where the frequencies overlap in both amplitude and intensity. You’re not really sure if the whale is actually quiet, or if it’s vocalizing but the boat noise is overriding or masking it. So we have to do a lot of recordings with boats and without boats. Then after our field season ends in April, we go back to Texas A&M and I do my computer analysis to try to pick out the whale signals and filter out other noises.”
On the eight tapes made so far this season, Paco says he’s been lucky in recording certain specific “events.” He’s come upon a group of Gray Whales feeding. “It used to be thought their feeding was nonexistent in Baja, but now more and more evidence supports the fact that they feed opportunistically,” he says. There were no boats in the area at the time, and Paco was able to pick up some “feeding signals” through the hydrophone. He’s also recorded several instances where the whales are socializing together, or exhibiting sexual behavior.
He’d begun by successfully matching the seven different types of Gray Whale signals that Dahlheim had detected at San Ignacio Lagoon. Since then, Paco has been able to classify three entirely new signals in Magdalena Bay, for a total of ten identifiable “calls” so far. “The last one was my most interesting,” Paco says, his excitement building. “Because I could only record it when there were boats around. I did this just three times on two different occasions, so admittedly it’s a very small sample. But I call it the ‘annoyance signal,’ because it’s a kind of negative response. And this is the same signal that was recorded at Sea World a year ago, when they were taking blood samples from the juvenile Gray Whale, J.J., in captivity there. So it was not even the same source, but it produced the same effect!”
This was more than intriguing. On the one hand, Gray Whales that come right up to small boats obviously aren’t “annoyed.” Indeed, precisely the opposite would seem to be the case. On the other hand, here at San Carlos, besides the industrial ship traffic the whales often found themselves surrounded by whale watching vessels – probably many more than at the San Ignacio Lagoon. Thinking back over my time at San Ignacio, I couldn’t help but be impressed with how conscientiously those skippers maneuvered around the whales. While the number of pangas on the lagoon at any given time had been allowed to increase from twelve to sixteen in 1999, overcrowding was never a factor. Guides like Pachico and Maldo certainly took people into the proximity of the whales, but nobody ever chased them. Here in Magdalena Bay, that same level of awareness didn’t exist. That is what Paco’s studies were aiming to improve.
Paco was saying: “I get criticism from some of my fellow marine mammalogists, who say ‘Why do I spend so much time with Gray Whales? They’re so ugly, they look like giant cucumbers or slugs!'” Who says that? I asked. “People that are jealous of our research,” Paco responded with a laugh, then continued: “Well, it’s true that Gray Whales are not streamlined like a Humpback or a Blue Whale. Or cute like a beluga. But they are so graceful. Filled with expression.”
Some of them were beginning to become “friendly” in Magdalena Bay. Paco said he’d noticed that, early in the season, “mothers actually put their bodies in between the boat and the calf. Then as the calf grows older and more curious, the mother allows more contact.” For Paco, after working around Gray Whales for eight years, 1998 marked the first time he’d touched one. “It was a calf and I could see its eye looking into my eyes. I knew we were talking. I didn’t say anything. This is an experience a lot of people have had in different ways, but I know it’s there. They’re trying to save us from our human side, I guess.”
I asked what he meant by that. “Well, I firmly believe that we have detached ourselves from nature, with automobiles and satellite TV and microwave ovens and so on. That to me is one of the reasons why we don’t protect nature. We have to feel a part of it first. The Gray Whales serve to connect us again.”
As the sun faded over Magdalena Bay, I sat on a promontory not far from the School for Field Studies. I watched for whale spouts and mused upon their echoes. Roger Payne, in describing the musical commonalities between human songs and Humpback Whale songs, has written: “This commonality of aesthetic suggests to me that the traditions of singing may date back so far they were already present in some ancestor common to whales and us. If this is true it says that the selective advantage of singing and the laws upon which we humans base our musical compositions (laws we fancy to be of our own invention) are so ancient they predate our species by tens of millions of years.”
That was a wild and wondrous thought for a scientist, not dissimilar from Paco’s feeling that he and the baby Gray Whale were “talking.” I reflected on two of my friends having been suddenly inspired to sing as the whales approached them. For one, it was a chant she had not thought of in years. Jim Nollman, among the pioneers in interspecies communication, tells a story in his latest book (The Charged Border) about donning a wetsuit and taking a “huge, floating drum” out among the Gray Whales off the California coast in the mid-1970s. When I met with Nollman, he told me the same story but with a twist.
Nollman said: “I was going into the water ten miles off the coast of Mendocino in January, in fifteen-foot swells and a boat about the size of this table. It’s also the white shark breeding ground for the West Coast. I can’t believe I was doing that, I was nuts! Anyway, there were times when I’d be floating around out there with this big wooden drum that had tongues cut out of the top, like you see in craft fairs today. I’d made outriggers for it, and a seat, so I could actually sit inside the drum.” Nollman called it a “whale singer” and, he wrote, was hoping to evoke “whale songs heard on record, in the ocean, and especially in the human imagination.” However, “if the drum tipped too much to either side, water flowed in through the tongue slits.”
He said he wasn’t having a whole lot of luck and “the swells are getting up to twenty feet. One moment you’re at the crest and the next moment in the valley, it’s very disorienting. My boat is gone, I don’t know where my crew members went. For some reason, I wasn’t freaked. All of a sudden, I had this jolt of being examined. It was very strong and I don’t know how to explain it, except that I felt like my brain was a room and somebody was walking around inside of it. A few seconds later, this Gray Whale came right up beside me and made eye contact. Just stared at me. I’ve never felt so scrutinized, almost invaded, but there wasn’t any feeling of danger. No, it was a feeling of trust. Of surrender.”
I sent David Gude a transcript of the conversation I’d taped interviewing Jim Nollman. David had been a musician and a sound engineer for a record company, and long been fascinated by the acoustics of whales. He’d been the one of my traveling companions who called the whales over with his song, on my first visit to the San Ignacio Lagoon. He wrote me from Los Angeles in response to reading the Nollman interview:
“Very mysterious. They may ‘hear’ or visualize by electrical stimuli. Maybe they see auras (‘Nollman: “they like to stare.”‘)
“[In Baja] four went by as I was swimming (my last morning). Dove under and called to them. (Always wondered what I would say). Said, ‘Hello,’ which came out, ‘Oh-oh.’ ‘Greetings from my world to yours,’ which came out: ‘ah ah, ah, ah ah, oh, ur.’ Very interesting. It was reduced to digital and tones….
“Maybe grays learned to project electromagnetic waves. Has anyone tested?….Huge mystery here. They rule the waterways. Man is 95% water! Lots to learn from them….”
As I finished reading the letter, that last phrase lingered. “Lots to learn from them….” I realized it was time for me – and getting time for the Gray Whales – to leave the Baja. Time to heed the call north. And I knew I’d have to follow, wherever the call took me.