When it's time to feed, humpback whales come ashore. Their mission: party until they're fat and happy. They need to build up their energy reserves by storing about a ton of fat per week to support their journey from arctic and sub-polar feeding grounds to the warm waters where they breed. The journey can cover thousands of kilometers over several months, and they must be ready to breed when they arrive. Perhaps because nature loves paradoxes, this massive, 60-meter-long, 40-ton predator has built a terrace by eating small sea creatures from around the world, including krill, a shrimp-like crab. the oceans. It is kept in cold waters at high latitudes.
We know a lot about how humpback whales eat. They filter seawater through sheets of keratin called baleen lining their upper jaw, which look like the bristles of an old toothbrush. They eat several thousand pounds of their small prey every day. You have to hunt the dense clams to get that much food. Once you've found a pack, you can use clever cooperative hunting tactics by swimming in circles and blowing bubbles. They then feed, opening their jaws and tending to find tightly packed prey by squirting thousands of liters of krill-filled water into their sticky pouches before sifting through their catch.
But for all the scientists who have studied this charismatic leviathan, nobody knows how fin whales (including humpback whales, blue whales, fin whales and cetaceans and others) feed. Their cousins, the odontocetes — sperm whales, belugas, dolphins and the like — use ultrasonic sonar signals to locate prey, but baleen whales lack this ability. Somehow they managed to find their small prey in the boundless ocean.
This is a mystery that scientists want to solve. In part because this is a huge gap in our basic understanding of popular species. Even more urgently, how baleen fish obtain their food has important conservation implications, particularly for a species of whale known as the North Atlantic right whale.
Feeding on rice-sized zooplankton copepods, the North Atlantic right whale has an unfortunate reputation for being one of the largest mammals on earth. Commercial whaling nearly wiped out the species in the early 1900s. In 1935, the League of Nations enacted right whale legislation. But unlike other species, whose numbers have declined, North Atlantic right whales have not recovered. Animal testing areas on the New England coast and in the Canadian Marine Basins overlap with areas of human activity. Collisions with boats and entanglements in fishing gear, and climate change combined with disruptions to their environment and their hunting lives have taken a heavy toll.
Recent estimates suggest that there are fewer than 350 North Atlantic right whales, of which only about 70 females are of childbearing age. According to some projections, the species could become extinct in the next two decades. Understanding how hatchlings track prey can help scientists predict where whales will forage and better monitor human activity in areas that could harm whales.
All of this is important to more than one cetacean species. North Atlantic right whales and other baleen whales are ecosystem engineers, feeding in deep water and then extracting nutrients from their guts near the surface that support the growth of small, plant-like organisms called phytoplankton. Phytoplankton, on the other hand, feed on krill, copepods, and other small swimming organisms known as zooplankton that are eaten by larger animals. Whale tissue contains a large amount of carbon dioxide, which can contribute to global warming: 33 tons for an average-sized whale. And when whales die, their carcasses sink to the ocean floor, where all manner of deep-sea creatures, from sleepy sharks to sulphur-loving bacteria, uniquely use these whale remains for food and shelter. The health of whale populations supports the health of many other species.
The most direct way to determine how fin whales find their food is to tag them with a device that can record their underwater and feeding behavior. For North Atlantic right whales, which are highly stressed by human activity, this is unlikely to happen, and direct human contact may make the situation worse. Luckily, the right whale has endangered relatives like the humpback whale. And one of the best places to see them eat is at the end of the world food.
In 2020, two weeks before the World Health Organization declared the Covid-19 pandemic a pandemic, I traveled to Antarctica to follow a team of researchers trying to understand how whales get food. I was a guest on the Polar Latitudes cruise line to observe the research of seven scientists on their cruise ship and give a lesson on the slow evolution of whales.
By participating in the tourist trip, the international research team based in America, Sweden and Japan saved a lot of money to reach the White Continent. Using two three-cabin inflatable boats, the Food and the Zodiac, the scientists offer whale cruises to the citizen scientists who regularly update their passengers on their research.
The team tests the whale feeding hypothesis through research on seabirds. Since the mid-1990s, Gabriel Nevitt-Davis of the University of California, Davis, has shown that dimethyl sulfide (DMS), a chemical released when phytoplankton are ingested by zooplankton, attracts seabirds, a group of carnivorous birds that include them Albatrosses belong. . , rocks and shearwaters and then feed on grazing zooplankton. It's a mutually beneficial arrangement: attracting seabirds with the scent of DMS protects phytoplankton from zooplankton. Even at the top of the food chain, your enemies' enemies are your friends.
The cruise team leader, Daniel Zitterbart of the Woods Hole Oceanographic Institution, a physicist who studies the behavior and ecology of whales and penguins using remote sensing techniques, and whale behaviorist Kylie Owen of the Swedish Museum of Natural History said they wondered if they are whales. It draws as follows: This is the same as DSM. If this is the case, the pursuit of chemicals in higher concentrations should, in theory, drive the whales to denser feeding grounds of krill and other phytoplankton than casual searches would allow. To find out, Zitterbart and Owen teamed up with Woods Hole whale biologist Annette Bombosh. zooplankton researcher Joseph Warren of Stony Brook University; Kei Toda and graduate student Kentaro Saki from Kumamoto University in Japan, who developed the technology to measure strain gauges; and Woods Hole oceanographer Alessandro Boccocelli, who pioneered the use of advanced digital markers to study cetaceans.
The team plans to track the humpback whales using special equipment that includes pressure sensors, accelerometers, magnetic compasses and hydrophones that record their underwater behavior with a radio transmitter. Their license allows them to tag a total of five whales, and they only have to do it in five days - the rest of the 12-day trip is spent on transportation. You have little room for error.
On February 28, we depart from the port of Ushuaia, Argentina, at the southern tip of South America, and spend the next two days of the leap year traversing the famous albatross-ridden Drake Passage 620 miles between America South and Antarctica. and gasoline. On March 1st we crossed the boundary known as the Antarctic Convergence and entered the calm, cold waters of the Southern Ocean. After boarding the Drake, the first thing we saw on the starboard side was Smith Island, part of the South Shetland Islands in British Antarctic Territory.
With the swelling in Drake's stomach behind us and the deadening effects of the motion sickness medication wearing off, I was now fully aware of my amazing surroundings. Icebergs, volcanic fragments and glaciers - some of the many types of ice here - mingle with the sea and sky to reveal all shades of blue. Cheerful gentoo penguin chicks follow their tired mother to feed. A crab-eating platinum seal sits on a floating ice couch and basks in the sun. I was blown away by the otherworldly beauty of this place.
On the morning of March 4th, I awoke at dawn in Paradise Bay, a beautiful harbor where whaling ships once docked. From my position on the Zodiac pontoon, I watched as the sun rose through a gap in the cloud cover, bathing the distant snow in golden light.
We are now in whale country and encounter groups of mammals swimming on the surface like logs, exhaling the humid air. The whale's wet breath mingles with the cry of the calving glacier and the murmur of the rain.
A day ago, scientists successfully marked the first hump. Passengers were delighted when scientists announced they had improved breakfast. Unfortunately, the whales continue to sleep while watching. But later that day they tagged a second whale, and this model was the subject, diving about 850 meters. The sensor data showed that the whales were feeding, and that's what they wanted to see.
This morning the team attempted to nominate a third player hoping he would be number two. Tremblingbeard, a tall, thin, fast-talking man, woke up at 5:30 a.m. and went on deck to see if there were whales and what the weather was like. The day looked promising. Whales have been sighted in the area and the water is calm, perfect for catching the brand who only has a few hours to catch the whale before the program expands and emerges.
At 6:45 p.m., a research boat was launched and scientists prepared to tag any spotted whales in the vicinity. A 20-foot carbon fiber mast extends from the bow and stern of the tug. Once within 10 yards of the animal, they use a pole to insert a four-sucker tag into an unmarked hump. Bombosh and Boccocelli sail across the open ocean on a school of whales. However, the team looks lazy. They didn't want to tag other sleeping whales, so Owen and Bombosh decided to target another group that looked more active.
Two humpback whales are visible from another view of the zodiac. Only the small dorsal fin and glossy black crest are visible. You don't look that big. But like a glacier, most of its mass is below the waterline. From a distance you can imagine the size of a humpback whale as it flaps its huge wings in the air, raises the tip of its tail before diving deep, or raises its body dramatically above the water.
Tremblingbeard held the big tie rod and stood upright, one foot in front and the other in the boat. Branding is hard work. To ensure a strong signal from the transmitter, the signal should be placed as close to the animal's back as possible, but not too close to the delicate skin surrounding the vent. As the marker ship approached the whale, Tremblebeard raised the mast and then threw the marker with enough force to send one of the animals into a time warp. The whale cried out and then disappeared from view - a common response - and the researchers moved quickly to film the pole, record the whale's GPS position and track the animal. Now all three have account attachments.
Once the tagged whale emerges, they spend the next few hours following it with their eyes and using a VHF receiver tuned to the tagged transmitter, staying within 300 feet of the animal to complete its routine not to disturb. . . Once installed, they had to get hold of the tags, each costing $10,000, to automatically store behavioral data from the whale during pre-programming. Now the team needs to choose a topic for collaboration. Owen explains, “The best thing to do is tag active whales that haven't eaten and they swim out to eat. Then researchers on the fishing vessels take water samples to see if the amount of krill and DMS has increased along the whale trail. If so, the whales would mark while they were feeding, they would have no tracks to follow." But humps are wild animals with their own agendas. "The stars really have to be right for things to work the way we want them to ' said Owen.
Visiting Antarctica means coming face to face with the forces that have shaped whaling for thousands of years. Whales underwent one of the most dramatic transformations of any vertebrate group as they descended from four-legged land animals to aquatic creatures. Like all living things, whales evolve under the influence of environmental changes. They began about 50 million years ago under Eocene greenhouse conditions. At that time, the southern supercontinent Gondwana was in the process of dissolving, and the ancient Tethys Sea stretched from the Pacific Ocean to the Mediterranean Sea. In the warm and shallow waters of the Tethys, the first whales went through the first stage of evolution: they became shorebirds. The front legs turned into lightning bolts, the nose became a breather, the ears were modified to hear while diving. About 10 million years after their four-legged ancestors roamed the waters with fins, whales had adapted so much to aquatic life that they could no longer walk on land.
The second phase of whale evolution occurs when the planet transforms into what is known as the Ice World. As the Eocene gave way to the Oligocene, tectonic forces took their final toll on Gondwana, splitting Australia, South America and Antarctica apart. When this landmass separation was complete, the Antarctic Circumpolar Current engulfed Antarctica, separating it from the warm waters and pulling nutrients from the depths, which contained abundant phytoplankton and zooplankton. This new current is so large and powerful that it is changing the circulation, temperature and productivity of oceans around the world. From this confluence of tectonic, climatic, and oceanic changes emerged the progenitors of the modern whale. The first representatives of this line ruled the seas 35 million years ago. Eventually, over millions of years, their descendants acquired the baleen plates and large body sizes for which this branch of the whale family became known.
Although Balinese tiles have been shaped by dramatic ecological and environmental changes throughout their evolution, this long history has not inoculated its modern descendants with the dangers of short-term major changes. In the 20th century alone, industrial whaling, armed with explosive harpoons and offshore processing vessels, killed more than two million whales, driving large populations to extinction and destroying their ecosystems. Many species have recovered from industrial disasters but are now facing a new round of existential threats. Warming oceans and commercial fishing are changing the supply of zooplankton on which whales depend for food.
Four days after watching the tag feature, I joined Warren, Zitterbart, Saki and Julien Bonnell on the Woods Hole Raider. The cruise ship had to make a trip to Chile's Free Station military base, an airfield on King George Island in southern Shetland, to transport the injured passengers to the nearest hospital in Chile. Concentrations in shallow ponds in the northern part of the island.
We've donned jackets, hats and gloves to battle the morning chill, but just a few weeks ago Antarctica peaked at 64.94 degrees Fahrenheit. The Antarctic Peninsula we are exploring is one of the fastest warming regions on earth. As a result, a large amount of ice is lost, which is bad for krill, Warren said. Juvenile krill seek shelter under winter sea ice and likely feed on algae growing beneath the ice.
Rising temperatures are not the only source of stress for krill. Demand for small species of krill has increased over the past two decades, particularly from the dietary supplement industry, the aquaculture industry promoting krill oil as rich in omega-3 fatty acids for humans, and the aquaculture industry using krill as feed for farmed fish. . . Whether the krill fishery is managed sustainably is controversial. But a 2020 study of krill hunting found that despite conservative catch limits for krill in the waters around the Antarctic Peninsula — less than 1 percent of the stock in the southwest Atlantic sector of the Southern Ocean — penguin numbers in the region are declining. , perhaps because fishing boats are concentrating their efforts in an area known for penguins. As the distribution and biomass of krill and other prey species change, predators, including whales, must adjust their feeding patterns.
As the Zodiac pulled away from the cruise ship, the researchers set up their equipment. They used sonar to send sound waves into the water, extracted images of krill and other animals they encountered, and projected images of the creatures moving through the water column onto Warren's laptop. The lower the ping level, the deeper the translator can "see". On the other hand, high frequency tones can detect smaller targets. The team used two frequencies, one low and one high, to look for small schools of krill floating 200 meters in the upper water column. The Warren Lab's mascot, Sir Ping-A-Lot II, is a little pig at the event. Warren joked as he threw the speaker into the sea, "It's about as exciting as it gets."
Krill aren't as fun to hunt as their predators, but the science behind the hunt has paid off big in recent years. The boat goes in the wrong direction until it reaches the side every two minutes to analyze the sea and collect water. Two handbag-sized and portable plastic containers contain equipment for measuring strain gauges in water samples. DMSN; The dryer removes the remaining moisture; The DMS ozonator produces elementary carbon dioxide; அத்தை பாட்டாயாவாவு பிர்பிர் அக்க்குக்க்குக்குக்குக்குக்குக்குக்குக்குக்கு: The amount of light is proportional to the amount of DMS. Previously, this type of analysis was done in the laboratory; Woods Hall researchers were able to fit TODA's strain gauge measurement setup into a small boat. "The ability to run DMS activation on Zodiac at this time is a major achievement," said Zitterbart. it enables, among other things, the analysis of water samples on site. "The water sample DMS symbol ಮನ್ ಕ್ತಿಕ್ ಕ್ತ್ ಕ್ತ್ಯು ಆನ್ಕ್ಮಾಮ್ಮಾಮಾನಿಮಿ" "Caution, we'll work in two minutes."
Monitor noise, collect water, conduct rehearsals. repeat There are no disturbing whales, blue skies, high winds and the noise of outboard boats. The speakers hovered above the seabed in the depths of the Gulf, the krill lifted before they lifted, we were halfway across. سراء لای ادرنالین گودیلہ ہے کے بساینساوی پیں کیمہلال کے Warren said, "Nobody has done much research of the bay so far, so "all the information we get from Warren is invaluable. Two krill plumes were returned to the ship and dozens of water samples were analyzed, data that will help researchers understand how krill and MSD are distributed in the Southern Ocean and plan for future changes to the baseline measurements.
In March, the short southern summer season approaches. Day after day he walked a dark road and began to walk towards the snowy sea. Humpback whales are migrating north to soon breed in the warm waters of America's West Coast. maybe that's why they're together. Researchers tagged the five whales allowed, but only two of them continued to feed. The other three sleep or relax on the beach. Due to a lack of interest in whale feeding, the team had to postpone their search. "በመጋቢት (ሀንችባክ) በጣም ከመሆናቸው ከመሆናቸው በላይ ነበር" ብሏል። "The first one is better because the whales are still building their population and are more active."
The water chemistry strategy needs to change. Initial analysis of the samples found by the researchers, as well as additional samples collected from passengers as part of the ship's Citizen Science program, showed less DMS than expected. There may be too much DMS in the water. But the other possibility is to assume that the mixed freshwater layer on top of the ocean weakens the signal. "Yuha Fizik's Yungy Yawasaswal," he says. In order to get clearer information about the chemistry, the researchers need to take samples from the sample.
Going forward, Zitterbart wants to move away from tourism cruise programs and focus on creating a detailed picture of what's happening in a bay. The plan is to take a cruise from the Antarctic Research Center to one of them and stay there alone with Zodiac. Map and water the chemistry of fish and krill in the same place continuously for several days and see how they have changed and when they return they catch the motherships.
But first they have to find a boat that will take them to the lower part of the world. For several years, paying customers have had to cancel planned cruise industry trips due to the pandemic. The usual excursions of the group are fully booked. The impact of the pandemic on the project "Five-year data is estimated to be available now," said Zitterbart. ក. They want to survive in 2024. In the meantime, we'll turn our attention to the other part of planetary research and expedite aid to the cetaceans who need it most.
For the past three years, Zitterbart, Owen and their colleagues at MSD have been studying the relationship between zooplankton and whales in Massachusetts waters in anticipation of the next Antarctic opportunity. Since the right whales in the North Atlantic could not tag them, they wanted to make the connection between the DMS hotspot and the Cape Cod Bay integration for right whales. ღამარილი მარილი მალალი მარალი მარერავები მარერავები მარილერი லிக்கு லிக்கு. The team searched the boat and plane without ID. Although the Antarctic survey did not identify the exact method by which fin whales hunt, Cape Cod's work after converting DMS to schools of krill or other means was only to determine if these whales might be present in parts of the ocean. DMS attention is high. If so, the whales are finding the DMS correct or following other signs that appear to be related to the DMS. Scientists can use the DMS readings to predict where and when the whales will be sighted.
Current efforts to protect North Atlantic right whales include current boat speed limits and visual and audio surveillance systems. For example, from January 1 through May 15, Cape Cod Bay has a speed limit of 10 knots for all vessels 65 feet and over. . Any time of year when whales are seen or heard in the area, ships of various sizes are asked to slow down and watch the creature. Whale Alert, a free app, displays current management locations and real-time whale tracking information on a map.
በኤምኤስዲ ምርምር ከዚተርባርት ጋር የብሔራዊ ውቅያኖስና አየር የስቴልዋገን የስቴልዋገን ባንክ ማሪን ማሪን መቅደስ ባልደረባ ኢኮሎጂስት ኢኮሎጂስት ኢኮሎጂስት ዴቪድ ዊሊ አካሄድ የመተንበይ አካሄድ ኃይል ኃይል ኃይል እና በተጨናነቁ ፍትሃዊ መንገዶች ትላልቅ ጀልባዎች ብለው ከሚንቀሳቀሱ ከሚንቀሳቀሱ ከሚንቀሳቀሱ ጋር መንገዱን መንገዱን በፍጥነት በፍጥነት። አይችሉም "እንደ ዲኤምኤስ ባሉ መተንበይ መሳሪያዎች ምላሽ ከመስጠት ይልቅ ማቀድ እንችችላ"ንችላ"
እ.ኤ.አ. በ 2021 ኦወን ዚተርባርት ዊሊ ግብረ አበሮቻቸው የዲኤምኤስ ደረጃዎች ከፍ ያለ የ የ zooplankton ክምችት እንደሚዛመዱ በኬፕ ኮድ ላይ ላይ ላይ ወረቀት የፊን ዌልስ ዲኤምኤስን ዲኤምኤስን ፣ በተጨባጭ በተጨባጭ አሁን ተመራማሪዎች የፊን በዚህ በዚህ መገናኛ የዲኤምኤስ ነጥብ ላይ እንደሆነ እንደሆነ እየመረመሩ ነው የመጀመሪያ ደረጃ ውጤቶች እንደሚያሳዩት ቀኝ ዌልስም ዌልስም ሆነ ዌልስ (ሌላ በኮፕፖድስ የሚመገቡ የባሊን የባሊን) ይህን ይህን አያደርጉም
ጉዳያቸውን ለማጠናከር ከዚህ አመት ፣ ተመራማሪዎች ሳምንቱ ኮድ ኮድ ቤይ በማሳቹሴትስ በማሳቹሴትስ ቤይ የሚገኘውን ቀኝ ቀኝ ቀኝ ዌል ከመድረሳቸው እና ሲወጡ እና በመደበኛ በመደበኛ በመደበኛ . ግባቸው ዓሣ ነባሪዎች ያህል ዲኤምኤስ ዲኤምኤስ በውሃ እንዳለበት እንዳለበት ለማወቅ ነበር ነበር ዊሊ ስለ ጥናቱ ጥናቱ "እርምጃውን ማወቅ, ከዓሣ ነባሪ ጋር ጠቀሜታ ጠቀሜታ ያለው እንደሆነ, ሁለት ዓመት ገደማ ገደማ.
ሕልሙ የዲኤምኤስ ደረጃ የሚሄድባቸውን መከታተል መከታተል መቻል መቻል, እና ስለዚህ ስለዚህ የሰሜን ስለዚህ ነባሪዎች የሳተላይት ምስሎችን ከጠፈር ላይ መሰብሰብ. የዱር አራዊት የዲኤምኤስ ደረጃ ዓሣ ዓሣ ዓሣ እስከሚቀጥሉበት ጊዜ ወደ አካባቢው ማዞር ወይም የአሳ የአሳ የንፋስ እርሻዎችን ለጊዜው መዝጋት ይችላሉ የአየር ንብረት የደመና መፈጠርን የዲኤምኤስ የዲኤምኤስ ከረዥም ጊዜ ጀምሮ ነበር ነበር ኬሚካሉ ከጠፈር እንደሚገኝ ደርሰውበታል። Ma ci vorranno dati satelliteri a risoluzione più alta di quelli attualmente available per prevedere i movimenti delle balene.
ፐር ለ ባሌኔ ዴል እና ቱቲ ግሊ ኦርጋኒዝም ኦርጋኒዝም ኩኢ ሲ ኮን ሎሮ ሎሮ ሎሮ ለ ኢንቱዪቶ አሪቫሬ አባስታንዛ ቬሎሴሜንቴ "ሴ ኮሴ ኖን ኖን ባሌኔ ባሌኔ ፍራንቼ ፍራንቼ ኢስቲንጉራኖ ኢስቲንጉራኖ ዴላ ኖስትራ ኖስትራ" ሲል ሲል ተናግሯል ተናግሯል Crede che la difficile ሁኔታ በ questa specie chiave sia il problema della conservazione del nostro tempo. Forse con l'aiuto delle megattere affamate in Antartide e di alcuni scienziati curiosi, le balene franche del Nord Atlantico e altri balenottere in pericolo un giorno rivendicheranno il loro posto come governmentanti del regno oceanico.
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