To crack the conundrum of just how much food 30- to 100-foot whales eat, scientists used data from 321 tagged whales spanning seven species living in the Atlantic, Pacific and Southern Oceans collected between 2010 and 2019. Each of these tags, suction-cupped to a whale’s back, is like a miniature smartphone—complete with a camera, microphone, GPS and an accelerometer that tracks movement. The tags track the whales’ movements in three-dimensional space, allowing scientists to look for telltale patterns to figure out how often the animals were engaged in feeding behaviors. By braiding this line of evidence with other data the research team collected, the scientists could generate the most accurate estimates to date of how much these gargantuan mammals actually eat each day and, by extension, each year. Credit: Duke University Marine Robotics and Remote Sensing under NOAA permit 14809-03 and ACA permits 2015-011 and 2020-016
New research co-authored by Nicholas Pyenson, curator of fossil marine mammals at the Smithsonian’s National Museum of Natural History, shows evidence that the world’s largest whales have been sold short. The study, published today in the journal Nature, finds that gigantic baleen whales—such as blue, fin and humpback whales—eat an average of three times more food each year than scientists have previously estimated. By underestimating how much these whales eat, scientists may also have been previously underestimating the importance of these undersea giants to ocean health and productivity.
Since whales eat more than previously thought, they also poop more, and whale poop is a crucial source of nutrients in the open ocean. By scooping up food and pumping out excrement, whales help keep key nutrients suspended close to the surface where they can power blooms of the carbon-absorbing phytoplankton that form the base of ocean food-webs. Without whales, those nutrients more readily sink to the seafloor, which can limit productivity in certain parts of the ocean and may in turn limit the capacity of ocean ecosystems to absorb planet-warming carbon dioxide.
The findings come at a pivotal moment as the planet faces the interconnected crises of global climate change and biodiversity loss. As the planet warms, the oceans absorb more heat and become more acidic, threatening the survival of food sources that whales need. Many species of baleen whales also have not recovered from industrial whaling during the 20th century, remaining at a small fraction of their pre-whaling population sizes.
“Our results say that if we restore whale populations to pre-whaling levels seen at the beginning of the 20th century, we’ll restore a huge amount of lost function to ocean ecosystems,” Pyenson said. “It may take a few decades to see the benefit, but it’s the clearest read yet about the massive role of large whales on our planet.”
Surprisingly, some basic biological questions remain unanswered when it comes to the world’s biggest whales. Marine ecologist and Stanford University postdoctoral fellow Matthew Savoca, one of Pyenson’s collaborators and lead author of the study, found himself confronted by one of these remaining mysteries: how much the massive filter-feeding baleen whales ate each day.
Savoca said the best estimates he encountered from past research were guesses informed by few actual measurements from the species in question. To crack the conundrum of just how much food 30- to 100-foot whales eat, Savoca, Pyenson and a team of scientists used data from 321 tagged whales spanning seven species living in the Atlantic, Pacific and Southern Oceans collected between 2010 and 2019.
Video and 3D-motion tags that are deployed on large whales with suction cups. Credit: Goldbogen Lab
Savoca said each of these tags, suction-cupped to a whale’s back, is like a miniature smartphone—complete with a camera, microphone, GPS and an accelerometer that tracks movement. The tags track the whales’ movements in three-dimensional space, allowing the team to look for telltale patterns to figure out how often the animals were engaged in feeding behaviors.
The data set also included drone photographs of 105 whales from the seven species that were used to measure their respective lengths. Each animal’s length could then be used to create accurate estimates of its body mass and the volume of water it filtered with each mouthful. Finally, members of the team involved in this near-decade-long data collection effort used small boats equipped with echo-sounders to race to sites where whales were feeding. The echo-sounders use sound waves to detect and measure the size and density of swarms of krill and other prey species. This step was crucial empirical grounding for the team’s estimates of just how much food the whales might be consuming.
By braiding these three lines of evidence together—how often whales were feeding, how much prey they could potentially consume while feeding and how much prey was available—the researchers could generate the most accurate estimates to date of how much these gargantuan mammals eat each day and, by extension, each year.
Because whales eat more than previously thought, they also poop more, and whale poop is a crucial source of nutrients in the open ocean. By scooping up food and pumping out excrement, whales help keep key nutrients suspended close to the surface where they can power blooms of the carbon-absorbing phytoplankton that form the base of ocean food-webs. Without whales, those nutrients more readily sink to the seafloor, which can limit productivity in certain parts of the ocean and may in turn limit the capacity of ocean ecosystems to absorb planet-warming carbon dioxide. Credit: Elliott Hazen under NOAA/NMFS permit 16111
For example, the study found an adult eastern North Pacific blue whale likely consumes 16 metric tons of krill per day during its foraging season, while a North Atlantic right whale eats about 5 metric tons of small zooplankton daily and a bowhead whale puts down roughly 6 metric tons of small zooplankton per day.
To quantify what these new estimates mean in the context of the larger ecosystem, a 2008 study estimated that all of the whales in what is known as the California Current Ecosystem, which stretches from British Columbia to Mexico, required about 2 million metric tons of fish, krill, zooplankton and squid each year. The new results suggest that the blue, fin and humpback whale populations living in the California Current Ecosystem each require more than 2 million tons of food annually.
To demonstrate how more prey consumption by whales increases their capacity to recycle key nutrients that might otherwise sink to the seafloor, the researchers also calculated the amount of iron all this extra whale feeding would recirculate in the form of feces. In many parts of the ocean, dissolved iron is a limiting nutrient, meaning that there might be plenty of other key nutrients such as nitrogen or phosphorus in the water, but a lack of iron prevents potential phytoplankton blooms. Because whales eat so much, they end up ingesting and excreting substantial amounts of iron. Prior research found whale poop has around 10 million times the amount of iron found in Antarctic seawater, and because whales breathe air they tend to defecate near the surface—just where phytoplankton need nutrients to help power photosynthesis. Using past measurements of the average concentrations of iron in whale poop, the researchers calculated that whales in the Southern Ocean recycle roughly 1,200 metric tons of iron every year.
Field measurements informing baleen whale prey consumption and nutrient recycling. Photos taken under NOAA permits 16111, 14809, 23095, and ACA permits 2015-011 and 2020-016. Credit: Alex Boersma
These surprising findings led researchers to investigate what their results might tell them about the marine ecosystem before industrial whaling slaughtered 2 to 3 million whales over the course of the 20th century. Based on whaling industry records of animals killed in the waters surrounding Antarctica in the Southern Ocean, the researchers used existing estimates of how many whales used to live in the region combined with their new results to estimate how much those animals likely ate.
According to the analysis, minke, humpback, fin and blue whales in the Southern Ocean consumed some 430 million metric tons of krill annually at the beginning of the 1900s. That total is double the amount of krill in the entire Southern Ocean today and is more than twice the total global catch from all human wild-capture fisheries combined. In terms of the whales’ role as nutrient recyclers, the researchers calculate that whale populations, before losses from 20th-century whaling, produced a prodigious flow of excreta containing 12,000 metric tons of iron, 10 times the amount whales currently recycle in the Southern Ocean.
These calculations suggest that when there were a lot more whales chowing down on krill, there must have been a lot more krill for them to eat. Savoca said that the decline of krill numbers following the loss of so many of their biggest predators is known to researchers as the krill paradox and that the decline in krill populations is most pronounced in areas where whaling was especially intense, such as the Scotia Sea between the Southern Ocean and the Atlantic Ocean southeast of South America.
“This decline makes no sense until you consider that whales are acting as mobile krill processing plants,” Savoca said. “These are animals the size of a Boeing 737, eating and pooping far from land in a system that is iron-limited in many places. These whales were seeding productivity out in the open Southern Ocean and there was very little to recycle this fertilizer once whales were gone.”
The paper posits that restoring whale populations could also restore lost marine productivity and, as a result, boost the amount of carbon dioxide sucked up by the phytoplankton—which are eaten by krill. The team estimates that the nutrient cycling services provided by pre-whaling populations at the start of the 20th century might fuel a roughly 11% increase in marine productivity in the Southern Ocean and a drawdown of at least 215 million metric tons of carbon, absorbed and stored in ocean ecosystems and organisms in the process of rebuilding. It is also possible these carbon reduction benefits would accrue year over year.
“Our results suggest the contribution of whales to global productivity and carbon removal was probably on par with the forest ecosystems of entire continents, in terms of scale,” Pyenson said. “That system is still there, and helping whales recover could restore lost ecosystem functioning and provide a natural climate solution.”
Pyenson said he, Savoca and others are pondering what the impact of whales might be if the team had been less conservative with their estimates, as well as a potential line of research comparing the relatively recent losses of large mammals in the sea to those lost on land, such as the American bison. Though based at Stanford, Savoca will continue his work this fall at the Smithsonian collecting samples from its extensive baleen whale collections.
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World’s largest whales eat more than previously thought, amplifying their role as global ecosystem engineers (2021, November 3)
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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.
That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.
“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”
The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.
Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.
Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.
Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.
Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.
Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.
“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”
The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.
North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.
Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”
Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.
Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.
For Dello, the “fingerprints of climate change” were clear.
“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”
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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.
On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.
They call it “Big Sam.”
The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.
It didn’t die alone.
“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.
She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”
“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.
The head alone, she said, is about the size of a baby elephant.
The discovery was a long time coming.
The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.
“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.
When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”
“It contains about 100 to 300 bones per square metre,” she said.
Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.
About a year ago, they found the second adult: Big Sam.
Bamforth said both dinosaurs are believed to have been the elders in the herd.
“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.
“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”
The genders of the two adults are unknown.
Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.
The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.
She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.
“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.
“It’s pretty exciting.”
This report by The Canadian Press was first published Sept. 25, 2024.
TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.
Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.
Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.
The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.
The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.
It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.
Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.
Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.
Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.
Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.
Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.
The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”
