James Cheshire
[Editor's Note] A person's geographic location can be represented by the x,y,z axis, as can the animal's location.
With the advent of satellites, radar, DNA sequencing, infrared cameras, sensors, and mobile phone applications, physical traces that were once left on the ground, in the air, and in the water have been able to pass through these devices into computer chips. Instead of relying on serendipitous events and a handful of manually recorded data points, researchers process and analyze billions of bytes of behavioral, physiological, and environmental data to understand animal movement and whereabouts.
"Where the Animals Go" tells the "detective story" of geographers who care about animals. For thousands of years, animals have been tracked based on their footprints, excrement, feathers, destroyed plants and nests, and now, in the information age, GPS trackers are used to track elephants threatened by poaching in Africa, collars that record the strength of magnetic fields are used to reveal the trajectory of badgers in underground caves, and seals glued to sensors transmit temperature and salinity data back to the waters of the southern hemisphere... With the addition of more new technologies, scientists can not only get a closer and more comprehensive understanding of the whereabouts of wild animals, but also understand unprecedented nature through the data transmitted by animals, and explore better ways to protect the earth.
With the permission of the publisher, this article is excerpted from the chapter "Whale Watching on Facebook" in the book, and together we go to understand the story of scientists tracking whales, from harpoon to Facebook, with technological innovation, we know more and more about the deep sea.
Where do animals go, James Cheshire, Oliver Uberti, translated by Tan Lingdi, Houlang | Hunan Fine Arts Publishing House, December 2021
As a teenager, I had the privilege of following the school to Iceland. The highlight of the journey is a short flight to the Westermanna Islands, which are across the sea from the south coast of Iceland. I went to Hema, the largest island in the archipelago, and climbed the Erdefell Volcano – the stones on which still retained the warmth of the 1973 eruption – and stood at the top of the mountain, impressed by the view: the ice sheets of the island to the north and a series of islands with steep shores to the south. Encouraged by the spectacular scenery, I later chose geography when I went to college. I always hope to be back there one day.
After 13 years, I finally came back, and the scenery is still there. But this time I was not focusing on the ice sheets or the islands, but on the sea between them. I came to hunt for killer whales with Filipa Samarra of the Reykjavik Institute of Oceanography and her colleagues, where they hunt for breeding herring in the summer. I also learned about Samara's research through the team's Facebook page, Icelandic Orcas, where they shared fieldwork and photos with thousands of people online.
Fishermen in northeastern Iceland encounter many killer whales while catching herring. Börkur Kjartansson, a fisherman who reported the sighting, sent photos of his sightings to the Icelandic Orcas. Image from Icelandic Orcas Facebook.
The first morning I arrived I received a message from Samara that her observers had spotted whales off the coast of Cape Stoll at the southwestern tip of the island. We made an appointment to meet at the pier at 9:30 AM. After a few moments, we left the dock and headed into the waves. The captain of the Marvin was volker Deecke (from the University of Cumbria), an expert in whale acoustics. "You're not seasick, are you?" He asked, while putting down the hydrophone outside the ship's side. I tried to stand firm, and before he thoughtfully answered for me, "Well, there's always a faint time," I replied, "No." On that day, the North Atlantic was relatively calm. Dirk turned off the engine, and the clicks and whistles of killer whales began to be heard from the hydrophone. Dirk had years of experience listening to whales and knew what they were saying: "They're foraging," he said, "heading northwest!" A commotion is coming soon. Our gaze and camera lens followed the seabirds that had plunged into the water and turned to a flock of black fins that undulated in the waves.
We managed to drive the boat to them and start taking pictures. Astri M M. M. van Ginneken, from the Orca Survey, is responsible for classifying and archiving each killer whale we see. She is a veteran of photography and knows it's different at first glance. It's not like I'm just shooting aimlessly in a row, every time she presses the shutter, she's well thought out. Trained in the film era, when it took money and time to take every photo, she said, "The more photos you take at sea, the more work you have to do back on shore." It's harder to get a usable photo than it sounds. Killer whales move quickly, dive into the water frequently, and change direction from time to time, making it difficult to keep up. All morning, I saw only a hazy pile of black fins, white waves, and blue waters, which to pre-1970 researchers looked like killer whales.
In Shervoo, Norway, killer whales can be seen in the fjords. Between October and February, both killer whales and humpback whales prey on herring to increase their protein reserves. Visual China figure
At the time, people counted directly as whales swam past boat sides or observation stations. Since the population is not counted according to individuals, the population size is not clear. It wasn't until the 1970s that Michael Bigg and colleagues at Fisheries and Oceans Canada began to focus on populations along the Pacific coast of North America. They found that different individuals could be distinguished by details of the killer whale's dorsal fin and saddle spot. For example, isa whale IS086 missing a large piece of its dorsal fin, while IS045's saddle spot ends are thinned, creating a long trail of aircraft trail marks.
Photographs of individual whales can be compared with other eyewitness records to map the trajectory and social activities of a whale over time. There are two major findings in such studies: 1) not all killer whales migrate, and 2) not all killer whales hunt the same prey. In the North Pacific, for example, there are "residents" who remain off the coast of British Columbia all year round to feed on fish, and there are "mobile whale mouths" that hover between California and Alaska, foraging for whales and seals. There is no interaction between the two groups of killer whales, and there are obvious genetic differences; it has even been suggested that the two be divided into different species. In Iceland, Samara's team is studying killer whales in the North Atlantic using photo-identification methods to see how different the migratory habits and feeding habits of individuals in the population are.
A century ago, in front of the whale to be studied, the researchers held up not the camera, but the harpoon. It may sound unbelievable now, but the earliest whale tracking devices were basically giant pushpins with barbs, each engraved with a unique identification number and mailing address. Whalers send these marks back to the researchers and tell them the approximate time and place of the whale hunt in return for cash. Some of the returned markings reflect the long migration of whales, but whaling was so popular at the time that many whales were killed just a few days after being marked. And unlike cyclologies of birds that can be identified multiple times in different places, harpoon markers provide only two data points: the time it hits a live whale, and the other is the time it is pulled out of a dead whale.
The amount of data extracted from the whaler's logs will be larger, but it will still be the same as killing the whales. In 1931, Charles Townsend, the curator of the New York Aquarium, after browsing a collection of whaling logs on shelves at the New Bedford Public Library in Massachusetts, concluded that by depicting on the map "the locations where a large number of whales were captured, a lot of information about the distribution of whales can be learned, and their migration can be learned."
Over the next few years, Townsend began to do his best to search for whaling logs. He traveled along the coast of New England to the whaling towns mentioned in Moby Dick—Nantucket, Salem, and Stonington—and obtained dozens of journals from libraries, historical societies, and even private collections. In total, Townsend reviewed records of more than 1,600 voyages by 744 ships between 1761 and 1920. He asked the New York cartographer R. W. W. Richmond circled all 53,877 whaling sites. The whaling sites of different months are represented by different colored circles and are drawn into four maps: 2 sperm whales (36,908 loci), 1 right whale (8,415 loci), humpback whales (2,883 loci) and bowhead whales (5,114 loci) combined into 1.
It is one of four original maps from Charles Townsend's 1935 report, titled "Distribution of Sperm Whales," which depicts a record of 36,980 captures between October and March of the following year, according to the North American whaling log.
We put data on 4 species of Thomson on a graph showing where American whalers had caught them in the past. In many ways, the distribution of whaling sites reflects not so much whale habits as whalers' preferences. To help you understand the past, we've also drawn the fictitious Route of the Pequod from Herman Melville's novel Moby Dick.
These maps were the first to shed light on the whale's movements and ranges, and thanks to the Wildlife Conservation Society of Canada, digitizing them, researchers continue to use them to compare where animals went then and now.
By the 1950s, there were more attempts to obtain data from live whales, although as we'll see next, these attempts are still far from modern ethical standards. Perhaps the most widely circulated expedition at the time was when Paul Dudley White went to measure the heartbeat of whales. White was President Eisenhower's cardiologist and, outside of his job, he was also interested in how mammalian heart rates change with body shape. The resting heart rate in humans is 60 to 100 beats per minute, although a heart rate of 40 beats or less has been recorded in athletes. White knew that the larger the mammals, the slower their hearts beat, but he wondered how slow they could go.
In 1953, White's team recorded a beluga whale heart rate of 12 to 20 beats per minute in the Bering Sea. The methods they use are disgraceful. To secure the animal to the side of the boat, they stabbed the harpoon head into the side of the beluga whale's body, which had been "alternating dives and sprays throughout the process, frantically trying to escape." Ignoring the whale's suffering, White concluded that it was possible to obtain a whale electrocardiogram in its natural environment, and three years later led an expedition to the coast of Baja California to look for gray whales. They plan to "place two electrodes under the tough gray skin of adult whales and pass through the fat layer without causing serious injuries." Two wires were dragged on the electrodes to the speedboat carrying the electrocardiograph. However, things did not go as planned.
Travel records published in National Geographic show white vividly describing the scene when they last tried to connect electrodes: "Two harpoon guns firing at the same time. The line quickly loosened from the muzzle reel. The upright whale shook violently and fell to the side, causing a white splash. The hit whale immediately broke free, forcing White to admit that "the weapons we use to catch heartbeats are not up to the task."
Over time, people gradually stopped taking the hardline line of the 50s and replaced it with a more sympathetic perspective on the natural world in the 60s and 70s. Perhaps the strongest catalyst for this shift — at least for whales— is Roger Payne, founder of the Ocean Alliance, a marine conservation group. In 1967, he began analyzing humpback whale sounds with Scott McVay of Princeton University. Neither is an experienced cetologist. Payne had previously studied how bats and owls used sound for echo localization, and McVeigh was the administrative worker. As "laymen" in a way, they discover something that has been overlooked from a whole new perspective: whales singing. The sounds they make underwater are not random, but complex and rhythmic sequences. In 1971, they wrote their findings into a famous paper published in the journal Science under the title Songs of Humpback Whales.
"Humpback Whale Song" recorded by Roger Payne, founder of the Ocean Conservancy Ocean Alliance
As Payne argues in Among Whales, there was no technical reason why people in the 1920s failed to adopt low-invasive research methods such as photo recognition: "I suspect that no one uses photographic identification only to be limited by the way of thinking at the time: the main content of reliable research always involves examining animal carcasses — which scientists use without thinking." It never seems to have seriously occurred to anyone that much more data would be available from each animal if harmless means were used. ”
By 1979, National Geographic stopped reporting on Paul Dudley White's heroic use of harpoons and instead became one of Payne's biggest supporters, reporting on his relentless exploration of whale protection. The magazine commissioned the largest one-time release of recordings in record history: 10.5 million records featuring whale songs, allowing readers to enjoy the accompanying article "Humpback Whales: The Mysterious Song".
To clarify how much progress has been made in cetaceanology since then, I visited Mark Johnson and René Swift of the Sea Mammal Research Unit (SMRU) at the University of St Andrews in Scotland. Johnson's office overlooked the North Sea, like an inventor's workshop, full of electronics of all levels. Downstairs, Swift sat at a desk surrounded by various machines and boxes of salt water. Together, they have developed some of the most advanced ocean tracking devices for researchers around the world to use. Johnson crammed state-of-the-art technology into the equipment, which was then ravaged by Swift to ensure they could withstand wind and waves, extreme temperatures and pressure changes as they drifted at sea.
Johnson showed me a mouse-sized sensor called digital sound recording tags (DTAGs) that can be adsorbed on the surface of a whale by a suction cup, and after a few days it will fall off and float to the surface for recovery. Each beacon is equipped with a magnetometer and accelerometers that record every pitch and roll of the whale. DTAGs differ from other marine beacons in that they also record the clicks, hums and whistles of toothed whales located with sonar. During echolocation, these sounds are reflected back by nearby objects and surfaces, and the whale's brain translates the echoes heard to sense the surrounding environment and possible prey like radar. DTAGs are able to collect 64GB of data in a matter of hours. Since our human brain does not have the audio processing power of whale brains, how to convert huge sound files into formats that we can understand has become a major problem for Johnson. A few years ago, he slightly modified an image called an echogram to show how whales "see" things through sound.
After looking at hundreds of echo maps, Johnson became an expert in deciphering predators' evasion strategies. "Imagine someone who deliberately hits you with a car. What should you do? How do you use the least amount of energy to keep yourself alive? You have to wait until the last moment and then rush to the side. "For fish, it works to swim to the side at the last minute because the sound beam used for whale positioning is narrower. Once the fish leaves the beam, it may seem to the whale to be gone.
This is an echo map showing the echo intensity received by an echo-localized Brinell beaked whale. The wider columns represent a sparser click, and the narrow columns represent a "buzz," or a period of rapid clicking. The object furthest from the whale appears at the top of the image: from left to right represents the passage of time. Darker and clearer places represent strong echoes of stationary obstacles, and blurrier places represent echoes of moving objects, such as fish in flight. The whale shown in the picture is chasing a fish.
The development of new devices and technologies shows how our understanding of this animal has changed. Swift said: "In the beginning, we used a harpoon to load something on the whale because we wanted to know where the 'resource' went. Today, we put trackers for protection. "DTAGs, for example, can also help researchers assess the effects of ocean noise on whale behavior. The noise generated by human activities may not be as dramatic as the crude oil spill, but it is also harmful, even life-threatening, to animals that perceive the world by sound. In 2014, Patrick Miller (from SMRU) led an international team to observe the effects of beaked whales exposed to noise, a group most pronounced by strandings affected by sonar. They selected a herd of beaked whales near the Atlantic island of Jan Mayen, put a DTAG on one of them, and then played the noise into the sea for 35 minutes. When the volume reached 98 decibels underwater — roughly the equivalent of the sound of a submarine passing by — the whales began to swam around to swim toward their boat. When they raised the volume to 130 decibels, the whale changed its mind, almost made a 180-degree turn, and dived deeper, setting a record for both the length and depth of the dive: 92 minutes long and 2,339 meters deep.
Until the beacon fell off after 7 hours, the whale behaved abnormally. He hadn't made a click or hum in the time since he was disturbed by the noise, and he had been making those noises constantly before. In the days since, the researchers have also seen fewer whales in the area, suggesting that the noise has also disturbed other whales.
It seems that it is not only whales that are positioned with echoes that are affected by the noise. Northern right whales in massachusetts Bay have a hard time hearing their kind amid the constant clamor of ships. Disruptions in communication have forced many right whales to forage alone, reducing the chances of reproduction. Jeremy Goldbogen of cascadia Research Collective did experiments similar to Miller's and found that even smaller military sonars stopped blue whales from feeding for up to 62 minutes. For the world's largest animal, a slight halt to eating can greatly affect calorie intake. Goldbergen estimates that blue whales eat 19 kilograms of krill per minute before being disturbed by noise. If you eat less than an hour, you will eat more than a ton less food—enough calories to feed all the organs for a day.
Disturbed by the noise, the northern bottle nose whale stopped feeding and went on a record deep dive.
Back at her desk on the shore, Filipa Samara was surrounded by cameras, wetsuits and several dozing researchers adjusting to the polar days of the Icelandic summer. She was reviewing a photograph taken by Van Schönecken the day before, and a photo that could be used for identification needed to clearly show the complete dorsal fin and saddle spots. The ideal is to take a picture from each side of each whale, as each side has its own characteristics. Looking at her collating these pictures, she realizes that to take good pictures, both the photographer and the boat driver need to be experienced and can predict where the whale will surface next. Perhaps to make me feel better about the bunch of blurry pictures I took, Samara said the whales of the North Atlantic were notoriously difficult to photograph: "Some days they won't let us get close."
Successful days may have surprising discoveries. For example, in July 2014, Samara saw an unusually familiar male. She thought to herself, "I know this whale. I've seen these traits. She looked through the old photographs on file and knew who it was: IS038, last seen in 1994. If you haven't seen a whale in years, researchers speculate that it's dead, so Samara finds the reunion extraordinary: "When you realize it's a whale that no one has seen in 20 years, it feels amazing."
Thanks to these photos, we began to gain a more complete picture of the life of the North Atlantic whales. Compared to the resident and mobile whale populations studied by Bigg et al. in the North Pacific, the feeding habits and social groupings of North Atlantic whales appear to be more complex. Icelandic whales spend the winter in the Glendaphieze area west of Iceland, where they hunt for herring, and most of them migrate to the Westmanna Islands in the summer. However, there are groups that migrate south and spend the summer in places where there are not so many fish near Scotland. Samara's instincts told her that the whales' feeding habits might have changed and they had eaten seals off the coast of Scotland. Due to her lack of skills, she had to turn to Facebook for help.
Whales come closer to shore, close to cruise routes around orkney and Shetland, so the public can easily take photos and upload them. "I didn't start out on Facebook," Samara said, "and then a colleague told me that he seemed to have seen whales in Iceland on Facebook." I decided it was best to sign up for an account myself. Sure enough, people were photographing the whales that Samara had studied in Iceland last winter. This is confirmed by a photograph of a female killer whale, Mousa (NUMBER IS086), which has a distinctive notch in her dorsal fin. Oddly enough, she and her cohort of whales are trying to use the seawater to wash seals off the reefs off the coast of Scotland. Do they actually eat both fish and mammals?
Photo recognition helps researchers link whale sightings in different seasons and locations.
On my third day in the Westmanna Islands, the Malvern's engine broke down. We drifted in the North Atlantic for a few hours before another survey ship came to tow us back to shore. The next day, the ship's engine also broke down. The reduction in the number of days of field expeditions was disappointing, but the Facebook page "Icelandic Killer Whale" allowed research to continue. While we were stranded on shore, Samara often went up to this page to see what was happening over there in Scotland. By noon on Monday, July 11, she had seen several photos of killer whales posted at the Fair Island Bird Observatory and Hotel: it was Moussa's herd of whales — and they were devouring two gray seals. Samara was particularly happy: "It's amazing! This confirms what we have been thinking all along. Now there is conclusive evidence that whales do change their feeding habits. ”
As the North Atlantic's fish stocks are dwindling, it is unclear whether these whales are choosing to eat seals on their own initiative or being forced to do so. In any case, humans and whales still have lingering feelings about industrial-scale whaling, and considering that the puzzle that has plagued researchers for a century can make up for the missing piece by photos or videos posted by tourists on Facebook, it is still remarkable.
Editor-in-Charge: Wang Yu
Proofreader: Zhang Liangliang