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World's largest whales eat more than previously thought, amplifying their role as global ecosystem engineers – Phys.org

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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 . 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.

Researchers find whales are more important ecosystems engineers than previously thought
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.

World's largest whales eat more than previously thought, amplifying their role as global ecosystem engineers
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.

Researchers find whales are more important ecosystems engineers than previously thought
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 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.


Explore further

Study suggests climate change could prevent recovery of southern right whales


More information:
Matthew Savoca, Baleen whale prey consumption based on high-resolution foraging measurements, Nature (2021). DOI: 10.1038/s41586-021-03991-5. www.nature.com/articles/s41586-021-03991-5

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'Use this technology to monitor the progression': How space tech can help the world fight the pandemic – USA TODAY

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SpaceX and NASA Crew-3 mission finally launch into space after delays

After several delays, the SpaceX and NASA Crew-3 mission finally launched into space with four astronauts.

USA TODAY, Storyful

Michael Strahan, former football star and host of “Good Morning America,” will be taking off with a crew of five other passengers on Dec. 9, amidst a global pandemic and rising cases of the new omicron variant.

Strahan won’t be the first civilian in space. In September, the Inspiration4 launch sent four civilians (a physician’s assistant, an aerospace worker, a professor and a billionaire) into orbit. In October, William Shatner became the oldest person to go into space, at the age of 90.

Civilian spaceflight launches have had a shining spotlight in a time when COVID devastated regions all over the globe. Some, like Prince William, have even criticized the obsession on spaceflight, saying billionaires and companies should focus more on addressing issues closer to Earth.

But could technology developed for space help us battle the pandemic?

An article released in September in the peer-reviewed journal Nature Medicine investigated how space-based technologies could be used to help manage and prevent pandemics.

How much a seat into space costs: William Shatner went to space. Here’s how much it would cost you.

Telemedicine was ‘developed by space agencies’

When astronauts are in space, for example, their medical information is meticulously tracked, the paper says.

In fact, astronauts often run medical experiments in space to help researchers better understand how the human body reacts to the properties of space, according to Phil McAlister, director of commercial spaceflight at NASA.

For the SpaceX Inspiration4 launch, McAlister said, civilians conducted a series of experiments, such as drawing blood in space, and shared the data with researchers on Earth.

“Telemedicine was actually developed by space agencies as well in order to provide care, monitor the care of astronauts,” says Dr. Farhan Asrar, a medical doctor and global faculty member at the International Space University. Asrar was a contributor to the Nature Medicine article.

Similarly, Asrar points out, telemedicine can be used to monitor and assess COVID patients remotely without the risk of infecting healthcare workers.

Asrar says that wearable technology has already been used by Canadian astronauts to monitor several key parameters of health, such as blood pressure, temperature, breathing rate and heart rate, all of which were streamed hundreds of miles from Earth aboard the International Space Station.

These wearable devices can be used by healthcare workers to detect early on whether they are developing and spreading symptoms, the paper suggests. 

More: NASA launches spacecraft to test asteroid defense concept

Using satellite imagery to monitor progression

Satellite imagery could contribute to pandemic planning and the distribution of vaccines against COVID-19, according to the paper. 

Satellites launched into space have already helped plot disease transmission during the Ebola outbreak, the paper points out. In the fight against polio, satellite images found marginalized and previously unknown villages in Nigeria, assisting with eradication efforts.

“There are several parameters which you can monitor using satellites,” Asrar says. “We can monitor temperatures that are ideal for these infectious conditions so that if an outbreak is occurring, you can use this technology to monitor the progression.”

Asrar cites using satellite monitoring on mosquito populations as a potential way to predict outbreaks of malaria.

How does COVID-19 affect me?: Don’t miss an update with the Coronavirus Watch newsletter.

Isolation and developing techniques to preserve mental health

One more thing we can learn from astronauts is the science of managing isolation, the paper says. 

Astronauts often have to be in space for days or months on end, with little or no contact with their loved ones. In a similar sense, social distancing guidelines have prevented people from gathering and made those with limited technological resources even more isolated, the paper points out.

In another article published in Nature in May of 2020, astronauts shared ways that they dealt with isolation in space, including having a carefully managed daily routine and structuring work around an inspiring mission.

Both research papers suggest that by understanding how astronauts cope with isolation, we can develop better techniques for preserving our mental health during the pandemic.

Feel like you’re surviving, not thriving: Join us at Keeping it Together, a newsletter about wellness and living life amid COVID-19.

Follow Michelle Shen on Twitter @michelle_shen10

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NASA’s DART Kinetic Impactor Spacecraft Launches in World’s First Planetary Defense Test Mission – SciTechDaily

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NASA’s Double Asteroid Redirection Test (DART) spacecraft sets off to collide with an asteroid in the world’s first full-scale planetary defense test mission. Riding atop a SpaceX Falcon 9 rocket, DART took off Wednesday, November 24, from Space Launch Complex 4 East at Vandenberg Space Force Base in California. Credit: NASA/Bill Ingalls

Lighting up the California coastline early in the morning of November 24, a SpaceX Falcon 9 rocket carried <span aria-describedby="tt" class="glossaryLink" data-cmtooltip="

NASA
Established in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. It’s vision is "To discover and expand knowledge for the benefit of humanity."

“>NASA’s Double Asteroid Redirection Test (DART) spacecraft off the planet to begin its one-way trip to crash into an asteroid.

DART — a mission designed, developed, and managed by the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, for NASA’s Planetary Defense Coordination Office — is the world’s first full-scale mission to test technology for defending the planet against potential asteroid or comet hazards. The spacecraft launched Wednesday morning at 1:21 a.m. EST from Space Launch Complex 4 East at Vandenberg Space Force Base in California.

As just one part of NASA’s larger planetary defense strategy, DART will send a spacecraft to impact a known asteroid that is not a threat to Earth, to slightly change its motion in a way that can be accurately measured via ground-based telescopic observations. DART will show that a spacecraft can autonomously navigate to a target asteroid and intentionally collide with it. It’s a method called kinetic impact, and the test will provide important data to help humankind better prepare for an asteroid that might post an impact hazard to Earth, should one ever be discovered.

“The Double Asteroid Redirection Test represents the best of APL’s approach to space science and engineering: identify the challenge, devise an innovative and cost-effective technical solution to address it, and work relentlessly to solve it,” said APL Director Ralph Semmel. “We are honored that NASA has entrusted APL with this critical mission, where the fate of the world really could rest on our success.”

Andy Cheng

Andy Cheng, a Johns Hopkins APL planetary scientist and one of the DART investigation leads, reacts after the successful launch of the DART spacecraft. Cheng was the individual who came up with the idea of DART. He watched the launch from the Mission Operations Center at APL’s Laurel, Maryland, campus. Credit: Johns Hopkins APL/Craig Weiman

At 2:17 a.m. EST, DART separated from the second stage of its launch vehicle. Minutes later, mission operators at APL received the first spacecraft telemetry data and started the process of orienting the spacecraft to a safe position for deploying its solar arrays. Almost two hours later, the spacecraft successfully unfurled its two 28-foot-long roll-out solar arrays. They will power both the spacecraft and NASA’s Evolutionary Xenon Thruster – Commercial (NEXT-C) ion engine, one of several technologies being tested on DART for future application on space missions.

“The DART team overcame the technical, logistical and personal challenges of a global pandemic to deliver this spacecraft to the launch pad, and I’m confident that its next step — actually deflecting an asteroid — will be just as successful,” said Mike Ryschkewitsch, head of APL’s Space Exploration Sector. “It gives me a lot of assurance that if we ever have to embark on an urgent planetary defense mission, we have the people and the playbook to make it happen.”

[embedded content]

DART’s one-way trip is to the Didymos asteroid system, which comprises a pair of asteroids — one small, the other large — that orbit a common center of gravity. DART’s target is the asteroid moonlet Dimorphos, which is approximately 530 feet (160 meters) in diameter and orbits Didymos, which is approximately 2,560 feet (780 meters) in diameter. Since Dimorphos orbits the larger asteroid Didymos at a much slower relative speed than the pair orbits the Sun, the slight orbit change resulting from DART’s kinetic impact within the binary system can be measured much more easily than a change in the orbit of a single asteroid around the Sun.

The spacecraft will intercept the Didymos system in late September of 2022, intentionally slamming into Dimorphos at roughly 4 miles per second (6 kilometers per second) so that the spacecraft alters the asteroid’s path around Didymos. Scientists estimate the kinetic impact will shorten Dimorphos’ orbit by several minutes, and they will precisely measure that change using telescopes on Earth. The results will be used to both validate and improve scientific computer models that are critical to predicting the effectiveness of kinetic impact as a reliable method for asteroid deflection.

Double Asteroid Redirection Test Illustration

Illustration of NASA’s DART spacecraft and the Italian Space Agency’s (ASI) LICIACube prior to impact at the Didymos binary system. Credit: NASA/Johns Hopkins, APL/Steve Gribben

“It is an indescribable feeling to see something you’ve been involved with since the ‘words on paper’ stage become real and launched into space,” said Andy Cheng, one of the DART investigation leads at APL and the individual who came up with the idea of DART. “This is just the end of the first act, and the DART investigation and engineering teams have much work to do over the next year preparing for the main event — DART’s kinetic impact on Dimorphos. But tonight we celebrate!”

DART’s single instrument, the camera DRACO (Didymos Reconnaissance and Asteroid Camera for Optical navigation), will turn on a week from now and provide the first images from the spacecraft. DART will continue to travel just outside of Earth’s orbit around the Sun for the next 10 months until Didymos and Dimorphos will be a relatively close 6.8 million miles (11 million kilometers) from Earth.

A sophisticated guidance, navigation, and control (GNC) system, working with algorithms developed at APL called SMART Nav (Small-body Maneuvering Autonomous Real Time Navigation) will enable the DART spacecraft to identify and distinguish between the two asteroids and then, working in concert with the other GNC elements, direct the spacecraft toward Dimorphos, all within roughly an hour of impact.

Provided by the Italian Space Agency, the Light Italian CubeSat for Imaging of Asteroids (LICIACube) will ride along with DART and be released prior to impact. LICIACube will then capture images of the DART impact, the resulting ejecta cloud and possibly a glimpse of the impact crater on the surface of Dimorphos. It will also look at the back side of Dimorphos, which DRACO will never have a chance to see, gathering further data to enhance the kinetic models.

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Space can help to solve the biggest challenges facing our planet. Here’s how – Euronews

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The views and opinions expressed in this article are those of the author.

In Earth’s more than four billion years of existence, it has had so many monumental moments.

The first human to discover the use of fire, the first to invent the wheel. The first human to walk on the Moon, the creation of the internet. So much evolution. Earth has witnessed the formation of life, the destruction of species, advancements in technology and society, and, ultimately, the regression of its own health.

We are at a historical cornerstone in time right now. As forests burn with fire and cities flood with water, unprecedented challenges are facing Europe and the world at large. Right now is the moment to contribute with bold, shared ambitions to solutions enabled by space.

Ambition: More important than ever

Ambition. It’s a word I use a lot. Ambition is what has driven humans to achieve the momentous, the impossible, the unimaginable.

It is what drove Europeans to explore and cross the Atlantic to new lands and later to send the first radio signals across the same body of water. It drove Europeans to discover the antibiotic penicillin and to save millions of lives with it thereafter.

To discover the theory of general relativity. To send the first space probe to perform a detailed study of a comet, dispatch a lander to its surface, and in a spectacular finale, land on the comet itself.

Ambition. Our planet’s youth is bursting with ambition (mixed with disappointment, anger, and a smudge of hope, admittedly and, well, understandably), as we saw recently in the streets of Glasgow and beyond during COP-26.

It’s been said that ‘ambition is the road to success. But persistence is the vehicle you arrive in’.

Space missions need the strength of a united Europe

So, we must move from ambition to persistence and action on what was laid out in Agenda 2025 (the strategy I developed to raise Europe’s game in space). A strategy that moves towards tangible, programmatic, and systematic commitments that create dialogue, inspiration, and change.

This is precisely what the Matosinhos Manifesto, the resolution adopted unanimously on 19 November 2021 at the European Space Agency’s (ESA) Intermediate Ministerial Meeting in Portugal, does.

It represents strength in numbers. The strength of a united Europe to deliver services to its citizens by accelerating space for the betterment and advancement of its people and of the planet overall.

A Europe that puts the user and citizen at the centre of its space activities.

Three initiatives to drive missions forward

The Manifesto is a commitment to focus on three initiatives called “Accelerators”, to speed up the use of space to solve today’s biggest challenges. To focus on space for a green future, to better understand the current state of Earth, to develop scenarios and solutions for sustainable life on this planet and to contribute effectively to achieving climate neutrality.

Then we must move from studying, observing, and understanding the planet towards action based on the deep knowledge that we gain. This is where the second Accelerator comes into play: The need to develop a rapid and resilient crisis response system to support stakeholders to decisively act on crises facing Europe.

And we cannot focus on the first two without ensuring their protection. Therein lies the third Accelerator: the protection of space assets to contribute to safeguarding and protecting our assets from space debris and space weather threats.

Beyond this, we also need our own ‘giant leap’ moment to inspire young Europeans to become more inquisitive about STEM topics so that we can continue to strengthen and enhance these fields for future generations.

New space economy

Inspirational missions will help drive innovation in the new space economy that is beginning to take shape. The Inspirators mission is to catapult Europe’s position as a global leader in space technology, innovation and deep-space scientific exploration.

To promote commercialisation, a modern, forward-looking European entrepreneurial landscape, multilateral cooperation, education, the development of human capital and STEM.

Think missions to icy moons, to unveil secrets about the origins of life or space exploration to take European astronauts beyond the International Space Station.

The passing of the Matosinhos Manifesto recently has created the necessary momentum to reach beyond our ambitions and jump-start into action.

The next steps and decisions will be formulated and taken at the European Space Summit and the ESA Council Meeting at ministerial level, both to be held in 2022.

  • Josef Aschbacher is the European Space Agency’s Director General. To learn more about the Accelerators and the Matosinhos Manifesto, please visit vision.esa.int

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