Thursday, August 12, 2021

 

Study takes unprecedented peek into life

 of 17,000-year-old mammoth

Peer-Reviewed Publication

UNIVERSITY OF ALASKA FAIRBANKS

Tusk_detail.jpg 

IMAGE: A CLOSE-UP VIEW SHOWS A SPLIT MAMMOTH TUSK AT THE ALASKA STABLE ISOTOPE FACILITY. BLUE STAIN IS USED TO REVEAL GROWTH LINES. SAMPLES WERE TAKEN ALONG THE TUSK USING LASERS AND OTHER TECHNIQUES, ALLOWING ISOTOPE ANALYSIS THAT PROVIDED A RECORD OF THE MAMMOTH’S LIFE. view more 

CREDIT: PHOTO BY JR ANCHETA, UNIVERSITY OF ALASKA FAIRBANKS

An international research team has retraced the astonishing lifetime journey of an Arctic woolly mammoth, which covered enough of the Alaska landscape during its 28 years to almost circle the Earth twice.

Scientists gathered unprecedented details of its life through analysis of a 17,000-year-old fossil from the University of Alaska Museum of the North. By generating and studying isotopic data in the mammoth’s tusk, they were able to match its movements and diet with isotopic maps of the region.

Few details have been known about the lives and movements of woolly mammoths, and the study offers the first evidence that they traveled vast distances. An outline of the mammoth’s life is detailed in the new issue of the journal Science.

“It’s not clear-cut if it was a seasonal migrator, but it covered some serious ground,” said University of Alaska Fairbanks researcher Matthew Wooller, senior and co-lead author of the paper. “It visited many parts of Alaska at some point during its lifetime, which is pretty amazing when you think about how big that area is.”

Researchers at the Alaska Stable Isotope Facility, where Wooller is director, split the 6-foot tusk lengthwise and generated about 400,000 microscopic data points using a laser and other techniques.

The detailed isotope analyses they made are possible because of the way that mammoth tusks grew. Mammoths steadily added new layers on a daily basis throughout their lives. When the tusk was split lengthwise for sampling, these growth bands looked like stacked ice cream cones, offering a chronological record of an entire mammoth’s life.

“From the moment they’re born until the day they die, they’ve got a diary and it’s written in their tusks,” said Pat Druckenmiller, a paleontologist and director of the UA Museum of the North. “Mother Nature doesn’t usually offer up such convenient and life-long records of an individual’s life.”

Scientists knew that the mammoth died on Alaska’s North Slope above the Arctic Circle, where its remains were excavated by a team that included UAF’s Dan Mann and Pam Groves, who are among the co-authors of the study.

Researchers pieced together the mammoth’s journey up to that point by analyzing isotopic signatures in its tusk from the elements strontium and oxygen, which were matched with maps predicting isotope variations across Alaska. Researchers created the maps by analyzing the teeth of hundreds of small rodents from across Alaska held in the museum’s collections. The animals travel relatively small distances during their lifetimes and represent local isotope signals.

Using that local dataset, they mapped isotope variation across Alaska, providing a baseline to trace the mammoth movements. After taking geographic barriers into account and the average distance it traveled each week, researchers used a novel spatial modeling approach to chart the likely routes the animal took during its life.

Ancient DNA preserved in the mammoth’s remains allowed the team to identify it as a male that was related to the last group of its species that lived in mainland Alaska. Those details provided more insight into the animal’s life and behavior, said Beth Shapiro, who led the DNA component of the study.

For example, an abrupt shift in its isotopic signature, ecology and movement at about age 15 probably coincided with the mammoth being kicked out of its herd, mirroring a pattern seen in some modern-day male elephants.

“Knowing that he was male provided a better biological context in which we could interpret the isotopic data,” said Shapiro, a professor at the University of California Santa Cruz and investigator at the Howard Hughes Medical Institute.

Isotopes also offered a clue about what led to the animal’s demise. Nitrogen isotopes spiked during the final winter of its life, a signal that can be a hallmark of starvation in mammals.

“It’s just amazing what we were able to see and do with this data,” said co-lead author Clement Bataille, a researcher from the University of Ottawa who led the modeling effort in collaboration with Amy Willis at the University of Washington.

Discovering more about the lives of extinct species satisfies more than curiosity, said Wooller, a professor in the UAF College of Fisheries and Ocean and Institute of Northern Engineering. Those details could be surprisingly relevant today as many species adapt their movement patterns and ranges with the shifting climate.

“The Arctic is seeing a lot of changes now, and we can use the past to see how the future may play out for species today and in the future,” Wooller said. “Trying to solve this detective story is an example of how our planet and ecosystems react in the face of environmental change.”

Other institutions contributing to the study included Florida State University, Montanuniversität Leoben, Liaocheng University and the National Park Service.

Isotopes reveal the lifetime mobility of an Arctic woolly mammoth


Peer-Reviewed Publication

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE (AAAS)

From the isotopes inside a 1.7-meter-long tusk, researchers recreated the life history of one Arctic woolly mammoth that lived more than 17,000 years ago, offering some of the first evidence that woolly mammoths traveled vast distances. Their findings provide a window into the lives of these now-extinct creatures, including their preferred habitats and extensive lifetime range. Despite being one of the most widely studied and iconic ice-age creatures, very little is known about the natural life history of the woolly mammoth, as fossils alone provide only static and often singular glimpses into their lives. Thus, the home range and mobility of mammoths – where and how far the large creatures roamed throughout their lives – remains largely a mystery. However, since regular migrations across great distances characterize the mobility patterns of their living elephant relatives and other Arctic animals, it is assumed that woolly mammoths exhibited similar behaviors. One method of potentially reconstructing the mobility patterns of long-dead mammoths is through the analysis of oxygen and strontium (Sr) isotopes that become incorporated into the animals’ teeth and tusks during life. Strontium isotope ratios (87Sr/86Sr) in soils and plants reflect the underlying bedrock geology, which vary across landscapes. As animals eat these plants, 87Sr/86Sr patterns from the region become incorporated into tissues. Thus, the 87Sr/86Sr ratios contained in tissues that continually grow throughout life, like mammoth tusks, for example, can provide a record that can be used to trace an animal’s movement over time. Using the tusk from a male woolly mammoth that lived in what is now mainland Alaska more than 17,100 years ago, Matthew Wooller and colleagues assembled a high temporal resolution isotopic record that reveals – in great detail – the mammoth’s movements during its ~28-year lifespan. The record shows repeatedly traveled routes across a geographically extensive range, with the animal covering enough of the Alaska landscape during its 28 years to almost circle the Earth twice. The results also illustrate the regions the animal frequented during different life stages, including as an infant and juvenile when part of a herd, as a more broadly traveling prime-aged adult, and during its final years, where, in a small region in northern Alaska, it likely succumbed to starvation.

Study investigates how arctic-alpine plants respond to global warming


500 million measurements on the impact of climate change

Peer-Reviewed Publication

UNIVERSITY OF BONN

Dwarf birch 

IMAGE: THE DWARF BIRCH (SHOWN HERE WITH REDDISH LEAVES) COULD BENEFIT FROM CLIMATE CHANGE. view more 

CREDIT: © ROLAND PAPE / UNIVERSITY OF SOUTH-EASTERN NORWAY

It is the most comprehensive study of its kind to date: Researchers at the University of Bonn and the University of South-Eastern Norway have studied how two characteristic arctic-alpine plant species respond to global warming. They did this by analyzing almost 500 million of their own readings from the mountainous region of Norway. The analyses show that potential consequences of climate change are extremely dependent on the specific location of the plants and that deciduous species in particular will benefit from warming. The result would be a further increase in the trend toward greening of the arctic-alpine regions. The study is published in the journal Ecosphere.

The Norwegian mountains can be pretty darn inhospitable during the colder months. Nevertheless, there are plants that cope splendidly with the biting temperatures. They include the dwarf birch Betula nana and the black crowberry Empetrum hermaphroditum. Both thrive in arctic-alpine conditions; this makes them typical representatives of tundra vegetation.

Up until now, it has been unclear how the growth of dwarf birch and crowberry is influenced by specific environmental conditions. In the alpine regions of Norway, a project has been underway for 30 years that aims to change that. "We wired up some of the plants here and fitted them with so-called data loggers that record the measurements," explains Prof. Dr. Jörg Löffler from the Department of Geography at the University of Bonn. A pin-like sensor records the diameter of the trunk - minute by minute, 365 days a year, to an accuracy of less than a thousandth of a millimeter. At the same time, the researchers measure solar radiation, temperature in the root zone and just above the soil surface, and soil moisture.

Shrinkage against frost damage

In the current study, researchers analyzed nearly 500 million measurements from 40 plants between 2015 and 2019. "We mainly studied how the microclimate, that is, the conditions encountered by the individual plant, affects its growth," says Svenja Dobbert, who is doing her doctorate in Prof. Löffler's research group. This revealed a striking rhythm in both dwarf birch and crowberry: During the colder months, their trunk diameter shrank significantly in each case - a process that was reversed in the spring. However, it was not until late summer that the deficits were made up to such an extent that actual growth began.

CAPTION

The dwarf birch (shown here) loses its foliage in winter, but the crowberry is evergreen.

CREDIT

© Roland Pape / University of South-Eastern Norway

"Due to low temperatures in the colder months, there is hardly any liquid water available for the plants," Dobbert says, explaining the finding. "They also reduce their trunk diameter by even actively reducing the water content of their cells to avoid frost damage." Just how important this strategy is for both species to thrive is demonstrated by another observation: Plants that shrank very little during the winter often showed little or no growth the following summer.

A second important finding: The deciduous dwarf birches usually grew better after a mild winter. They therefore seem to generally benefit from warmer winters. With the evergreen crowberries it was the other way around. "In cold winters, there is usually less snowfall," Löffler says. "This could be an advantage for evergreen species because they can then keep up photosynthetic activity for longer and hence enter the growth phase earlier in the spring." It is therefore possible that climate change is causing an increasing spread of deciduous species and a concomitant displacement of evergreen species. Since the leaves of deciduous plants have a comparatively large surface area (in contrast, those of evergreen species are usually needle-like), this effect could contribute to the further greening of arctic-alpine regions.

The microclimate is crucial

"However, our results also show that microclimatic conditions can be extremely different depending on the location," explains Löffler. For instance, at exposed, windy locations, snow cover tends to be very thin. The deciduous dwarf birch however requires a sufficiently thick insulating layer of snow in winter. It then has to use fewer resources to protect itself from frost. Without this warming blanket, the dwarf birch has a difficult time. The evergreen crowberry, in contrast, benefits from the extra sunlight during such snow-free periods. "Overall, our measurements prove that global climate data provide little valid evidence for local vegetation effects," emphasizes the geographer. "Studies like ours can potentially help us better model such complex effects and in turn better predict the effects of climate change on plant life."

Participating institutions:
In addition to the University of Bonn, the University of South-Eastern Norway was involved in the study.

Publication: Svenja Dobbert, Roland Pape & Jörg Löffler: Contrasting growth response of evergreen and deciduous arctic-alpine shrub species to climate variability. Ecosphere, https://doi.org/10.1002/ecs2.3688

CAPTION

The crowberry (shown here) is evergreen, but the dwarf birch loses its foliage in winter.

CREDIT

© Roland Pape / University of South-Eastern Norway

#LEGALIZEDRUGS

No adverse cognitive effects of ketamine or esketamine for treatment-resistant depression

Peer-Reviewed Publication

WOLTERS KLUWER HEALTH

August 12, 2021 – Used for the treatment of depression that does not respond to standard antidepressant medications, the anesthesia drug ketamine – and the related drug esketamine, recently approved for depression treatment – has no important adverse effects on memory, attention, or other cognitive processes, concludes a systematic review of medical research in the September/October issue of Harvard Review of Psychiatry. The journal is published in the Lippincott portfolio by Wolters Kluwer.

"Current evidence suggests that ketamine and esketamine do not appear to exert significant deleterious neurocognitive effects in treatment-resistant depression," according to the new research, led by Breno Souza-Marques, BA, and Lucas C. Quarantini, MD, PhD, of Federal University of Bahia, Salvador, Brazil. In fact, some cognitive functions improved 7 to 13 days after repeated ketamine infusions.

Evidence supports cognitive safety of ketamine and esketamine for depression treatment

Ketamine is a widely used surgical anesthetic that produces a detached, dreamlike state. Multiple studies have shown that at low doses, ketamine can have rapid antidepressant effects – typically improving mood within 24 hours to 7 days. Similar benefits have been reported with esketamine, a version of the drug recently approved for use in patients with treatment-resistant depression. Although ketamine is not yet approved for treatment of depression, some physicians prescribe it for that purpose on an "off-label" basis.

However, there are potential safety concerns with ketamine, which is "a highly sought-after recreational drug," according to the authors. Studies have reported memory impairment after long-term recreational use of ketamine, as well as in medical studies in which healthy volunteers received just one infusion. That's particularly worrisome because memory problems and other cognitive symptoms – such as difficulties with thinking and concentrating – are a key aspect of major depressive disorder. Cognitive symptoms may continue even after mood improves.

To investigate the cognitive safety of ketamine and esketamine, Mr. Souza-Marques, Dr. Quarantini, and colleagues searched the medical literature for studies in which one of these drugs was given to patients who had treatment-resistant depression. Definitions vary, but most experts consider depression "treatment-resistant" if it persists after the patient has tried at least two different antidepressants.

The team identified 14 studies that collectively involved 1,019 patients: one study of esketamine nasal spray for 44 weeks, seven studies of a single ketamine intravenous infusion, and six studies in which patients received six ketamine infusions over two or three weeks. Neuropsychological performance assessment was variable for the ketamine studies (1 study at 40 minutes, 1 study at 24 hours, 1 study at 3 days, and 1 study at 7 days), while the esketamine study performed repeated assessments at 28 days, 20 weeks, 32 weeks, and 44 weeks.

The esketamine study showed no changes in cognitive performance. Five studies of ketamine actually reported improvements in memory, processing speed (the time it takes to complete a mental task), or cognitive flexibility (the ability to switch between mental tasks or thoughts).

Only one of the 14 studies reported cognitive impairment after ketamine treatment. Memory was worse 24 hours after six ketamine infusions, and processing speed was worse 24 hours after a single infusion, but these deficits were no longer present seven days after treatment. Moreover, the group that received multiple infusions showed improved processing speed, cognitive flexibility, and memory. Despite this encouraging evidence, further studies are needed to assess the longer-term neurocognitive effects of these drugs.

Some studies showed that individuals who had certain cognitive attributes before treatment—poorer attention, slower processing speed, or better memory—were more likely to respond to ketamine. The researchers conclude: "Results suggest possible neuropsychological profiles predictive of antidepressant response to ketamine, such as lower attention, slower processing speed, or higher working memory, that should be further assessed in future studies, as these results could provide time-saving evidence to clinicians and mental health practitioners."

Click here to read “Neurocognitive Effects of Ketamine and Esketamine for Treatment-Resistant Major Depressive Disorder: A Systematic Review.”

DOI: 10.1097/HRP.0000000000000312

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About the Harvard Review of Psychiatry

The Harvard Review of Psychiatry is the authoritative source for scholarly reviews and perspectives on a diverse range of important topics in psychiatry. Founded by the Harvard Medical School Department of Psychiatry, the journal is peer reviewed and not industry sponsored. It is the property of Harvard University and is affiliated with all of the Departments of Psychiatry at the Harvard teaching hospitals. Articles encompass major issues in contemporary psychiatry, including neuroscience, epidemiology, psychopharmacology, psychotherapy, history of psychiatry, and ethics.

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HYDROPOWER IS NOT GREEN

Over 260,000 kilometres of rivers at risk due to proposed hydro dams


Dams and reservoirs are the leading contributors to future loss of connectivity in free-flowing rivers around the world

Peer-Reviewed Publication

MCGILL UNIVERSITY

Over 260,000 kilometres of river could potentially be severed by planned hydroelectric developments according to McGill University researchers. The Amazon, the Congo, and the Irrawaddy are just a few of the rivers at risk of losing their free-flowing status if the proposed construction of new hydropower dams takes place. The study, led by World Wildlife Fund and published recently in Global Sustainability, showed that planned dams and reservoirs are leading contributors to the decline of free-flowing rivers around the world. It also provides a comprehensive list of science-based solutions to minimize the impacts of hydropower development in rivers.

“We used a dataset of more than 3700 potential hydropower projects and calculated their impacts on rivers worldwide,” says Prof. Bernhard Lehner from McGill University’s Global HydroLab, who created the underpinning global river maps. “It was sobering to learn that many of today’s remaining free-flowing rivers are at risk of being permanently transformed by new energy infrastructures.”

Moreover, the study also finds that all the proposed dams on free-flowing rivers would collectively generate less than 2% of the renewable energy needed by 2050 to keep global temperature increase below 1.5⁰ C - a small contribution with potentially devastating consequences to the remaining free-flowing rivers, and the people and wildlife that depend on them.

The researchers suggest that, as global leaders convene for a critical round of UN climate and biodiversity summits this fall, policymakers must consider the tradeoffs between hydropower development and maintaining healthy freshwater ecosystems.

Looking at the tradeoffs - Hydropower development vs. environmental costs

“It is true that hydropower is a source of renewable energy with relatively low carbon emissions,” says Günther Grill, a post-doctoral fellow at McGill who crunched the numbers and developed the spatial environmental assessment model to estimate the effect of future dams. “However, hydropower projects can permanently and irreversibly impact river and floodplain dynamics and functions, often in tropical wilderness areas with high biodiversity.”

The policy paper points to the fact that connected and healthy rivers deliver diverse benefits that are often overlooked: freshwater fish stocks that improve food security for hundreds of millions of people; delivery of sediments that nourish agriculture and keep deltas above rising seas; and floodplains that help mitigate the impact of floods and support a wealth of biodiversity.

“When it comes to river health, climate change and biodiversity loss, we can no longer afford to think of these as separate issues,” says Michele Thieme, lead freshwater scientist at World Wildlife Fund (WWF) and lead author of the study. “Rivers are powerful agents for keeping wildlife and communities healthy, especially in a warming climate, yet their ability to support life is threatened by hydropower dams in many parts of the world. The best policy solutions will be those that balance renewable energy needs with the many benefits of thriving freshwater ecosystems.”

Safeguarding free-flowing rivers while meeting climate targets and energy needs

In the paper, the researchers have compiled a list of science-based policy solutions to meeting climate targets and energy goals, while also safeguarding free-flowing rivers and their benefits to people and nature. These solutions include avoiding river fragmentation by exploring alternative development options, such as non-hydropower renewable energy, like solar and wind; minimizing impacts by siting dams in locations with fewer consequences on people and nature; restoring rivers through dam removal; or offsetting the negative impacts of dams on one river by formally protecting another, similar river.

“There has been a long history of conflicts, studies, and debate over how to both protect rivers and develop them sustainably,” adds Lehner. “With a pause in new developments caused by the global pandemic, anticipated further implementation of the Paris Agreement and high-level global climate and biodiversity meetings in 2021, now is an opportune moment to consider the current trajectory of development and policy options for reconciling dams with freshwater system health.”

The study: “Navigating trade-offs between dams and river conservation” by M.L. Thieme et al in Global Sustainability 4, e17, 1-7

DOI: https://doi.org/10.1017/sus.2021.15

The research was funded in part by WWF in Washington, DC and by McGill University in Montreal, Quebec, Canada.


 

New marmoset species discovered in Brazilian Amazon

“Schneider’s marmoset” is found in the highly threatened, but little-studied forests of Mato Grosso State

Peer-Reviewed Publication

WILDLIFE CONSERVATION SOCIETY

Schneider's marmoset 

IMAGE: NEWLY DESCRIBED SCHNEIDER'S MARMOSET view more 

CREDIT: RODRIGO COSTA-ARAÚJO

MANAUS, Brazil (August 12, 2021) – A team of scientists has discovered a new marmoset species in the Brazilian Amazon. Schneider’s marmoset (Mico schneideri), described in the latest issue of the journal Scientific Reports, is named after professor Horacio Schneider, a pioneer and major contributor to the research of diversity and evolution of monkeys.

The discovery was made by a team of researchers led by Rodrigo Costa Araújo, currently an associate researcher at Museu Paraense Emílio Goeldi. Araújo was funded in part by the Conservation Leadership Programme (CLP), a capacity-building partnership between WCS, BirdLife International and Fauna & Flora International (FFI).

The Amazon marmosets of the genus Mico are among the more diverse groups of monkeys and found only in the threatened forests of the “arc of deforestation,” a region that accounts for half of the global land use change in the past 30 years. Currently, there is no conservation response to address the losses of habitat and population decreases such marmosets are subjected to, primarily because they are poorly studied.

The total number of Amazon marmoset species remains unknown. In 2019 Araújo and his team discovered the Munduruku marmoset (Mico munduruku) from another area within the arc of deforestation. M. schneideri was described from marmosets known to researchers since 1995 but misidentified as M. emiliae.

The study notes the existence of 16 Mico species located in the “arc of deforestation” – an extensive region in the southern Amazon where the highest rates of land clearing and fires are concentrated. Further research is needed to assess the conservation status of M. schneideri and to investigate the southern portion of its geographical distribution. Additionally, continuing to uncover exactly how many Amazon marmosets occupy these forests will underpin the first step towards conserving this threatened group of monkeys.

The research was possible due to a scholarship provided by CNPq and funding provided by CAPES, FAPESP, FAPEMAT, Conservation Leadership Programme, Primate Action Fund Re:Wild, National Science Foundation, NERC and Idea Wild.

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WCS (Wildlife Conservation Society)

MISSION: WCS saves wildlife and wild places worldwide through science, conservation action, education, and inspiring people to value nature. To achieve our mission, WCS, based at the Bronx Zoo, harnesses the power of its Global Conservation Program in nearly 60 nations and in all the world’s oceans and its five wildlife parks in New York City, visited by 4 million people annually. WCS combines its expertise in the field, zoos, and aquarium to achieve its conservation mission. Visit: newsroom.wcs.org Follow: @WCSNewsroom. For more information: 347-840-1242.

 

Southeast’s gray foxes may be struggling for survival.

Competition for food from coyotes seems to be key to declining populations

Peer-Reviewed Publication

UNIVERSITY OF GEORGIA

Fox 

IMAGE: GRAY FOX POPULATIONS SEEM TO BE DECLINING IN THE SOUTHEAST, ACCORDING TO UNIVERSITY OF GEORGIA RESEARCH. view more 

CREDIT: SARAH WEBSTER

For generations, gray foxes have been part of the Southeastern landscape. They, along with red foxes, are among the carnivores that dine on a range of smaller animals, plants and berries.

But a new study published by researchers from the University of Georgia suggests competition for food from coyotes—a relative newcomer to the Southeast—may be putting pressure on foxes, particularly the gray fox.

“Gray fox populations, especially in the Southeast, seem to be declining, and have been for some decades,” said James Beasley, an associate professor in the UGA Warnell School of Forestry and Natural Resources whose doctoral student, Sarah Webster, wrote the study as part of her dissertation.

The study, published in the Journal of Mammology, was co-authored by Beasley as well as Warnell professor Michael Chamberlain and Warnell alumnus Joseph Hinton.

By looking at reports given by licensed animal trappers in South Carolina, where Beasley’s lab is located, it was clear to the researchers that the number of harvested foxes—particularly gray foxes—has been decreasing, while the number of harvested coyotes has increased.

“Here on the Savannah River Site, there are excellent historical trapping records and gray foxes used to be really abundant,” said Beasley. “But now we don’t see them nearly as frequently. That’s prompted questions of why—why are we seeing the reduction in these numbers?”

At the Savannah River Ecology Lab in Aiken, South Carolina, where the study took place, Beasley said habitats have changed dramatically over the years, from agricultural areas preferred by red foxes to forested areas more conducive to tree-climbing gray foxes. Also, food is abundant for generalist carnivores such as coyotes and foxes, which will eat a variety of plants and animals, and coyotes are now abundant in this landscape.

In the Midwest, where foxes and coyotes have lived together for hundreds of years, the species have found a way to carve out food sources without overlapping too much—scientists call this “partitioning.” But coyotes have only been in the Southeast since the 1970s, giving them far less time to sort out their overlapping food preferences.


CAPTION

Competition from coyotes (pictured) may be contributing to declining numbers in gray fox populations.

CREDIT

Sarah Webster

Still, Webster wanted more information about how coyotes’ and foxes’ food sources might differ between the regions. So, she used hair samples gathered from red and gray foxes and coyotes from both regions and from a variety of decades, including preserved samples from the Georgia Museum of Natural History. By measuring the amounts of carbon or nitrogen in the hair, Webster was able to assess the amount of overlap in diet between each species.

For example, a diet high in protein would manifest as a higher nitrogen content. Vegetation, such as fruits or grasses, translates as carbon in the hair samples. By noting the relative amounts of carbon and nitrogen content in hair samples, Webster was able to assemble a picture of how much diet overlap there was between each species in each region.

The results? There are significant regional differences in how coyotes and foxes dine.

“In the Midwest, we found there were significant differences in diet between species, whereas in the Southeast they overlapped significantly,” she said. In the Southeast, red and gray foxes had a large amount of overlap in their diets prior to the onset of coyotes, and that overlapping continued once coyotes arrived, according to more recent samples. “So, all three species are overlapping now in the Southeast.”

Beasley noted that the diet partitioning that takes place among these species in the Midwest is something that developed over hundreds of years, as coyotes and foxes learned to navigate the landscape around each other. There apparently hasn’t been enough time for that dynamic to play out in the Southeast.

“The question is, will that happen fast enough, before the gray fox populations continue to decline further?” he added. “It’s not exceptionally dire for the gray fox, but we now often find them closer to buildings or other marginalized areas. So, they may be finding other mechanisms to coexist with coyotes. But they do need forested areas.”

Habitat is one way, said Webster, that we can work to ensure future populations of gray foxes remain stable. When we understand the dynamics at play between the species, we can better plan for the future.

“We don’t have good evidence that we can effectively manage coyote populations on a large scale. They’re generalists, and they’re too flexible in their behavior and patterns. They will survive just fine,” said Webster. “So, a more effective approach likely would be to focus on the gray fox. Step one is to better understand how the gray fox population is doing by studying their population dynamics, and then going forward from there and trying to build effective management around the gray fox to ensure they continue to thrive in the Southeast.”


After historic Hurricanes Eta and Iota, NASA helps prep Central America for disasters to come

Business Announcement

NASA/GODDARD SPACE FLIGHT CENTER

Flooded Streets in San Pedro Sula 

IMAGE: THE STREETS IN SAN PEDRO SULA ON NOVEMBER 6, 2020. THE INFORMATION HERRERA AND OTHERS IN CENTRAL AMERICA RECEIVED IN 2020 INCLUDED SATELLITE IMAGES TO SEE THE STORMS’ DAMAGE TO POWER GRIDS, HIGHWAYS AND OTHER IMPORTANT PARTS OF THE LANDSCAPE. view more 

CREDIT: CREDIT: PHOTO COURTESY OF COORDINATION CENTER FOR DISASTER PREVENTION IN CENTRAL AMERICA

Shortly after Category 4 Hurricane Iota began to drench Central America on Nov. 16, 2020, Claudia Herrera watched from a helicopter as ruinous flood water inundated entire neighborhoods of La Lima, in Honduras’ Valley of Sula. In just three days, the catastrophic rainfall of Iota had flooded Ramon Villeda Morales International Airport in La Lima, as well as schools, healthcare centers, and other critical infrastructure in a region that serves as the country’s main economic engine.

The view from the helicopter was too familiar for Herrera, who leads the Coordination Center for Disaster Prevention in Central America, or CEPREDENAC for its acronym in Spanish. Two weeks earlier, Category 4 Hurricane Eta had battered the region, with Honduras bearing the brunt of the storm’s cataclysmic force. Herrera had been helping regional authorities plan their response to the storms’ destructive winds and heavy rain, which had also scarred important mangroves in Nicaragua and triggered deadly landslides in Guatemala.

Soon after Eta touched down in northern Nicaragua on Nov. 3, NASA’s Earth Applied Sciences Disasters program area began working with Herrera and other authorities in Central America to use satellite images and data to monitor damage and help teams on the ground analyze the affected terrain as they rescued people affected by the storm.

As thousands of people within and beyond the region joined forces to help, the impending impact of a second, virtually “twin” storm shocked everyone. Iota was going to make landfall within 20 miles of where Eta had.

“When we were warned about Iota, and we sent this information to the local authorities, we could not believe it—that it was possible that another storm was coming, and that it was going to affect us with the same magnitude almost simultaneously,” Herrera said. “We had not finished making damage reports, quantifying the damage of Eta’s impact, when we were already bracing for Iota’s impact.”

Eta destroyed highways connecting the Sula Valley to the rest of the country, adding another layer to the challenge of providing humanitarian support to people in need and creating a feeling of helplessness, Herrera said. The massive, coordinated efforts to help displaced communities find shelters took the help of everyone in the country—and beyond.

Teams flew in from the United States and Colombia to assist Honduran armed forces leading the way. Local partners in the private sector also provided helicopters and equipment. Local fishermen helped people trapped by floods in tight areas in their own small fishing boats. Remotely, NASA’s Disasters program provided products updated on a near real-time basis for teams on the ground.

The ability to operate nimbly while coordinating information transfer with NASA’s help was crucial for the team’s efforts as it helped the region connect with other geospatial organizations that also provided support, said Marcelo Oyuela, the lead geographic information systems engineer of the Central American organization.

“Sometimes there is a lot of data and information, but the knowledge that is missing is where that information is, where those initiatives are,” Oyuela said.

An Abundance of Storms

In unusually quick succession, Eta and Iota capped a disastrous hurricane season for Central America, which had not been hit as badly since Category 5 Hurricane Mitch in 1998. The storms contributed to a season that marked the fifth consecutive year with hurricane activity well above average.

Although the abundance of storms in 2020 does not guarantee hurricanes will become more frequent in the coming years, scientists say ocean warming is already changing hurricane behavior and expect that ocean warming will fuel more intense hurricanes in the future.

When Eta and Iota passed over the Caribbean’s warm waters, their wind speed increased drastically in under 36 hours as a result of a rapid intensification phenomenon scientists expect to become more common as ocean temperatures rise.

For the past few decades, hurricanes have been rapidly intensifying more often, and their forward motion has been stalling more, dropping more rainfall over confined locations. Eta, Iota and other major hurricanes contributed to that trend in 2020, which saw a record-tying nine storms intensify rapidly. These quick changes in storm strength can leave communities in their path without time to properly prepare.

“There’s no observed trend globally on the frequency of storms. Some years and some ocean basins have more and then less,” Tim Hall, a hurricane researcher at NASA’s Goddard Institute for Space Studies in New York, told NASA’s Earth Observatory in 2020. “But if you already have a hurricane formed, we have found that global warming signals are increasing a storm’s likelihood to stall, intensify into a major hurricane, and drop more rain.”

Eta and Iota also formed well past the time of year when major hurricane activity is expected to peak. As ocean and atmospheric temperatures continue to rise, major storms late in the season will likely become more common. The hurricane season officially runs from June 1 to November 30, and by early August, the Atlantic Ocean is primed for hurricanes.

A Global View for Regional Resilience

NOAA has predicted another highly active season for 2021. In Honduras, Herrera also expects a taxing season because of the damage and fear that lingers.

Herrera’s team continues to work closely with NASA’s Disaster program and other international government agencies and private groups. Their initiative is fully focused on strengthening resilience for each country in the region.

“Right now, there are already four countries affected with flooding—Honduras, Guatemala, Nicaragua and Panama—without even having entered the season of significant storms,” Herrera said in June. “We are taking all possible measures to prepare for this rainy season, but we have a very big challenge with the impact of hurricanes Eta and Iota still in the territory.”

Because other agencies also aid in response and recovery work after storms like Eta and Iota hit, the work of the Disasters team always requires a tremendous amount of coordination with local and international groups to streamline the flow of information.

One of the program’s priorities focuses on partnering with local and international groups to generate data-based products with a global view of Earth and applying that information down at the regional level, said David Green, who manages the program.

“We seek to develop trusted relationships within a cultural context with vulnerable communities and those able to take action, which means we bring in population data, we bring in economic information, we reach out to those at risk, as well as partners in humanitarian relief, including the Bureau of Humanitarian Affairs of USAID, the UN disaster groups in Panama, the mapping groups in Costa Rica, and the satellite agencies in Mexico,” Green said. “We collect that knowledge because we've learned to engage the village to build sustainable resilience.”

Header image caption: The streets in San Pedro Sula on November 6, 2020. The information Herrera and others in Central America received in 2020 included satellite images to see the storms’ damage to power grids, highways and other important parts of the landscape. Credit: Photo courtesy of Coordination Center for Disaster Prevention in Central America

By Roberto Molar Candanosa
NASA’s Goddard Space Flight Center