The Herbert W. Hoover Foundation is proud to have funded this research project and look forward to all of the future advances in the field that result from it. Article originally appeared on SciTechDaily.org. Original article can be viewed here. The scientific article can be viewed here.

A Rutgers Health study has discovered aerosolized plastics in neonatal tissue following in utero exposure.

Plastic pollution, including tiny particles smaller than a grain of sand, has become ubiquitous, affecting even newborn rodents, according to a Rutgers Health study published in the journal Science of the Total Environment.

Researchers have long understood that micro- and nanoplastic particles (MNPs), which enter the environment through oxidation and natural degradation of consumer products, are easily deposited in the human body through inhalation, absorption, and diet.

Experts also understand that these pollutants can cross the placental barrier and deposit in fetal tissues.

What’s been unclear is whether these particles remained in tissue long after birth. The Rutgers Health researchers found that they do, at least in rats. Their data that could have implications for human health.

“Nobody wants plastic in their liver,” said Phoebe A. Stapleton, an associate professor of pharmacology and toxicology at the Rutgers Ernest Mario School of Pharmacy, and the study’s senior author. “Now that we know it’s there – as well as in other organs – the next step is to understand why and what that means.”

Research Findings in Rodents

To assess the persistence of micro- and nanoplastic particles in neonatal tissue following maternal exposure, Stapleton and colleagues exposed six rats to aerosolized food-grade plastic powder for 10 days during pregnancy.

Rodents are good test subjects for this type of study, Stapleton said, because humans and rodents both possess a hemochorial placenta, meaning that maternal and fetal blood don’t come into direct contact during circulation.

Two weeks after birth, two newborn rats – one male and one female – were tested for micro- and nanoplastic exposure. In both cases, the same type of plastic that the mothers inhaled during pregnancy were found in the offspring’s lung, liver, kidney, heart and brain tissue. No plastics were found in a control group.

Stapleton said the findings are one more piece of evidence illustrating the potential dangers of micro- and nanoplastics in the environment.

“These results raise concerns for the toxicological impacts associated with MNPs exposure, maternal-fetal health, and systemic MNPs particle deposition,” the researchers wrote.

Micro- and nanoplastics are a ubiquitous pollutant, and have been detected in food, farmland, seawater, and snow. Plastics have even been found in the world’s deepest oceans and highest mountains.

These invisible pollutants are potentially hazardous to human health. An increasing body of evidence suggests a strong correlation between micro- and nanoplastic particles and cancer, inflammation, impaired immune function, tissue degeneration, and cardiovascular problems.

Call for Further Research and Policy Action

Stapleton said she hopes her findings help create a sense of urgency among policymakers to make more funding available for research.

“Without answers, we can’t have policy change,” she said.

Eventually, the persistence of these materials in human tissue could lead to greater regulation, Stapleton said. While plastics have undoubtedly improved consumer products, too little is known about their long-term health impacts. As researchers fill knowledge gaps, regulators will be better equipped to protect public health, she said.

“I don’t think we’ll ever get rid of plastics altogether,” she said. “They’re too important for modern life. But I do think we might get to a point where we’ll have some policies to indicate which ones are less toxic than others.”

Reference: “Identification of micro- and nanoplastic particles in postnatal sprague-dawley rat offspring after maternal inhalation exposure throughout gestation” by Gina M. Moreno, Tanisha Brunson-Malone, Samantha Adams, Calla Nguyen, Talia N. Seymore, Chelsea M. Cary, Marianne Polunas, Michael J. Goedken and Phoebe A. Stapleton, 6 August 2024, Science of The Total Environment.
DOI: 10.1016/j.scitotenv.2024.175350

The research was funded in part by a grant from the Herbert W. Hoover Foundation.

The Herbert W. Hoover Foundation is proud to have funded this research project and look forward to all of the future advances in the field that result from it. Article originally appeared on Phys.Org. Original article can be viewed here. The scientific article can be viewed here.

Most people find sharks threatening. Who doesn’t have an image in their mind of a menacing shark fin racing through the ocean in search of its next meal?

But it is the shark that is threatened.

According to Defenders of Wildlife, a national nonprofit dedicated to protecting imperiled species, 75% of shark species are threatened with extinction and up to 73 million sharks are being killed each year for their fins.

Habitats that were once secure places for sharks to give birth have also been affected. And the fact that sharks have long gestation periods, giving birth to relatively few young, and maturing late in life—complicates efforts at repopulation. And that’s a problem.

In a new paper published today (March 1) in Science Advances, authors James Sulikowski, a professor at Arizona State University and Neil Hammerschlag, a marine ecologist at the University of Miami, describe a new technology they developed capable of remotely documenting the location and time of birth of shark pups. This type of data will enable scientists to create ways to protect the sharks’ most vulnerable habitats, where they give birth.

“If they (the mother sharks) don’t have that suitable habitat, then their babies won’t be able to grow up. And if babies don’t grow up, we have no more sharks and literally, the ocean ecosystem would collapse,” explained James Sulikowski, senior Global Futures scientist at Arizona State University and director of the Sulikowski Shark and Fish Conservation Lab at ASU’s New College of Interdisciplinary Arts and Sciences.

The device is making waves in the scientific community—and for good reason.

“We’ve been trying to do this since we started studying sharks. This is our holy grail. We have really advanced shark science, 20, 30, 40 years,” said Sulikowski. “This novel, satellite-based technology will be especially valuable for the protection of threatened and endangered shark species, where protection of pupping and nursery grounds is a conservation priority.”

The paper outlines the deployment and results of an intrauterine satellite tag on two highly mobile sharks—a scalloped hammerhead and a tiger shark—to detect when birth occurs, leading to its name, birth-alert-tags (BAT).

Here’s how BAT works.

First the BAT is inserted into a pregnant shark. The egg-shaped technology is approximately 2 inches long and 1 inch wide. When the shark gives birth, the BAT pops out along with the pups and reaches the ocean surface. Once there, the device switches to transmitter mode sending messages announcing the time and location of the birth.

The BAT has already yielded remarkable results. Where it was once assumed that sand sharks gave birth inland, the scientists have learned that they are most comfortable having their pups in abandoned shipwrecks on the ocean floor.

“It was a total surprise,” Sulikowski said. “For most shark species we have no idea where they give birth or how far they must travel to habitats that are essential to their survival.”

Once habitats are discovered, efforts will be made to protect those areas, either by creating sanctuaries or expanding areas already set aside for this purpose.

The ultimate goal is to go global with the BAT.

Sulikowski wants to create a worldwide network of shark scientists to determine areas that are important to sharks and figure out how to protect them.

Persistence pays off

Sulikowski is enjoying his current success. “We’ve had every sort of failure that can happen,” he said. “We had battery failures. We had firmware failures, we had antenna failures. I felt like giving up multiple times. But thanks to my co-author, Neil Hammerschlag, we kept forging ahead and we didn’t give up.”

“Honestly, it feels incredible to have created technology that is going to revolutionize the way that we study sharks,” Sulikowski added.

Article originally appeared on UM News and Events. Original article can be viewed here. Published scientific article can be viewed here.

Unlike big land predators, the ocean’s top predators don’t avoid urban areas 

The world’s coastlines are rapidly urbanizing, but how this increased human presence may impact species living in the ocean is not fully understood. In a new study led by scientists at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, researchers tracked the movements of three shark species, bull, nurse and great hammerhead, in relation to the city of Miami. Given the chemical, light, and noise pollution emanating from the coastal metropolis, researchers expected sharks to avoid areas close to the city, but that’s not what they found.

Some animals, like pigeons and racoons, thrive in cities. These species, known as “urban exploiters,” often become dependent on human garbage for food. Other animals, known as “urban adapters,” may show some use of urbanized areas, but still largely rely on natural areas. On the other hand, some species such as land predators such as wolves are very sensitive to human disturbance. These “urban avoiders” avoid big cities.

“Few studies have investigated the movements of ocean predators in relation to urbanization, but since other studies have shown that land predators are urban avoiders, we expected sharks to be too,” said Neil Hammerschlag, director of the UM Shark Research and Conservation Program and lead author of the study. “We were surprised to find that the sharks we tracked spent so much time near the lights and sounds of the busy city, often close to shore, no matter the time of day.” The researchers concluded that the behaviors of the tracked sharks resembled that of “urban adapters”. The study speculates sharks could be attracted to shore from land-based activities, such as the discarding of fish carcasses.

The relatively high use of urban-impacted areas by the tracked sharks may have consequences for both sharks and humans. “By spending so much time close to shore, sharks are at risk of exposure to toxic pollutants as well as fishing, which could impact their health and survival,” said Hammerschlag. While shark bites on humans are rare, the study also pinpoints areas close to shore that could be avoided by human water users to reduce probability of a negative shark encounter, promoting human-shark coexistence.

The study, titled “Urban Sharks: Residency patterns of marine top predators in relation to a coastal metropolis”was published June 16, 2022 in the journal Marine Ecology Progress Series. 

 The study’s authors include: Neil Hammerschlag, Mitchell Rider from the UM Rosenstiel School, and Robbie Roemer, from Ocearch; Austin J. Gallagher from Beneath the Waves; and Lee Gutowsky from Trent University.

 This research was funded through support from the Ocean Tracking Network, the Disney Conservation Fund, the Save Our Seas Foundation, the National Oceanic and Atmospheric Administration (NOAA) Southeast Fisheries Science Center, the Batchelor Foundation, the Herbert W. Hoover Foundation, Ruta Maya Coffee, the International Seakeepers Society, and through a grant ‘Implementing a Marine Biodiversity Observation Network (MBON) in South Florida to Advance Ecosystem-Based Management’ funded under the National Oceanographic Partnership Program (NOPP, RFP ONR BAA #N00014-18-S-B007, in partnership with NOAA, BOEM, and NASA) and the US Integrated Ocean Observing System (IOOS) Program Office.

Originally published in The Canton Repository. Original article available here.

Curious eyes have been scanning how Cliff Linder and some other Stark County farmers have been taking care of their soil.

A five-year study called Stark Sustainable Soils Initiative is a project of the Ohio State University Extension Program and the university’s Center for Carbon Management and Sequestration.

Its purpose is to gauge how land management practices of local farmers impact soil health, crop production and the quality of nutrients. 

Linder operates a beef cattle and grain farm in the 7000 block of Nickel Plate Avenue NE in Nimishillen Township.

Linder grows “mostly hay,” he said. “Every four or five years I rotate them. We go to corn, soybeans, wheat and back to hay. They (the research team) check it on the first 6 inches, then the next 6 inches. They analyze it to see what nutrients are there, like potassium, phosphorous, nitrogen, zinc and copper, how much carbon is in the soil.”

Researchers also examine the crop growth on Linder’s farm.

They were looking for “growth and the nutrient uptake they took up in a year,” Linder said. “You have to keep putting nutrients back. You have to replenish. It doesn’t replenish itself.”

Stark Sustainable Soils Initiative at midpoint

Researchers are in the middle of the study. Stark County farms were selected because the project is being funded by the local Herbert W. Hoover Foundation. 

“We have perimeters to measure soil health just like we have perimeters to measure human health,” said Rattan Lal, the Ohio State University professor leading the Stark Sustainable Soils Initiative study.

“We selected farms that represent a wide range of function. The range could be from 20 acres to 200 acres. We don’t tell the farmers what they should do. We just select them based on different management practices.”

Lal is a professor of soil science and director of the Carbon Management and Sequestration Center at the university. His project also involves the Ohio State University Extension Stark County Office. Kent State University also is taking part.

Depending on what the study reveals, “we will make a recommendation to farmers,” Lal said. “You can adopt some practices which will improve the health of the soil. The reason we are doing the project is so we can promote one health concept. The one health concept means the health of soil, animals, people, the ecosystem and the planet are interconnected. Therefore, if the health of the soil goes down, everything else goes down with it over time.”

Drainage sediment goes to Gulf of Mexico

In all, 12 properties in Stark County are being examined by the research team. There is ongoing concern about soil erosion. The big-picture drainage pattern for this area is sediment carried off by liquid drainage, through a series of streams and rivers, eventually winds up in the Gulf of Mexico.

“It takes nitrogen, phosphorus and potassium with it,” Lal said “All marine life suffers. It leads to a lot of problems for our water.”

To ward off such soil erosion, Lal’s research team is encouraging no-till farming.

“When soil has a dark color, it is very fluffy, it is light in weight, it is very porous, it is a healthy soil,” Lal said. “We have an index – soil is healthy, medium healthy or not healthy. If it is not healthy, we will talk to the (OSU Extension) agent. We will advise what can be done.”

Another farmer participating in the study is Ken Blim, who has a grain farm in the 3300 block of Paris Avenue NE in Washington Township. Blim also practices land management to safeguard the health of the soil.

“We raise some cover crop,” Blim said. “After our wheat comes off in July, then in a short period of time we plant cover crops; some form of grass, some clover, some radishes. It kind of opens up the ground a little bit. It will enrich the soil. We will have some sunflower in the mix. It all has to do with good soil, you will have good crops.”

Part of the Stark Sustainable Soils Initiative study focuses on carbon storage, or sequestration, in the soil.

“It is an indicator of the soil health,” Lal said. “Some conclusions we have is organic matter should be 1.5% of the total weight of the soil. That means the soil is healthy.”

Originally published by Farm and Dairy. Original article available here.

EAST CANTON, Ohio — Soil is the foundation for a wide range of agriculture in Stark County. And while fields in the county don’t have as obvious of an impact on local water quality as farms in Lake Erie watersheds, they do affect water quality downstream, and plant, animal and human health around them.

That’s why researchers at Ohio State University and Kent State University are working on the Stark Soil Health Initiative, a project seeking to understand how farm management affects soil health and carbon storage on small farms in Ohio.

Researchers are working with 12 farms in Stark County and have completed two years of the five-year project. They discussed results from the first two years in a March 4 town hall, in East Canton, Ohio.

“We’re stewards of the land,” said Cliff Linder, a Nimishillen Township farmer who participated in the project. “We need to look down the road of generations to come … I’m only here a short time. Somebody else is going to take over that farm, or whatever, so I want to leave it better than what I got.”

Soil health

Part of the reason researchers wanted to look at soil health, said Heather Neikirk, Ohio State University Extension agriculture and natural resources educator for Stark County, is the “One Health” concept — “The idea that healthy soils give us healthy plants, which provide for healthy animals and ultimately, healthy humans.”

Nutrient management issues have been a big topic across the state. The Ohio Department of Agriculture introduced an agricultural fertilizer applicator certificate a few years ago, aimed at combatting nutrient management issues. And while farm fields in Stark County don’t run off into Lake Erie watersheds, they do drain into the Ohio River and eventually into the Gulf of Mexico.

Stark County was a good place to look at soil health, in part because it has a lot of different types of farms, and quite a few of them are actively using conservation practices already, said Neikirk. The county is also similar to the state of Ohio as a whole since it has large urban areas, as well as suburban and rural areas.

Farmers involved in the project said it is helping them get a better sense of what their soil looks like, and where they can improve it. It is also showing them how things like the carbon in their soil change from year to year.

“We’re all here to try to do better next year,” said Kenny Blim, a Washington Township farmer.

Farms

The farms had several different types of crop rotations. For example, six used corn-soybean rotations. Two consistently grew hay on the fields sampled. One was an organic farm with a highly diverse crop rotation. Researchers also sampled two woodland sites. The farms used a range of tillage practices, and about half used manure for fertilizer while the other half did not.

“The main thing that sort of holds all the farms in the project together is the soil type,” said Kathleen Bridges, a post-doctoral scholar at Ohio State’s Carbon Management and Sequestration Center. “We were specifically trying to find out or understand how management was affecting soil, so we had to make sure that we were using the same soil type.”

The soil type researchers focused on was Canfield silt loam. One of the farms did not have the same soil type, so researchers did not include it in their analysis.

Carbon

The hay fields and the woodland sites had higher levels of carbon than cultivated fields. No till fields were slightly lower in carbon than the different types of tilled fields, though there wasn’t a significant difference, Bridges said.

“I was expecting and I have been taught that no till is the carbon savior … But that’s not what we’re seeing here,” she said.

That’s likely because farms in the project that tilled were replacing more of the carbon lost through manure, and incorporating that carbon deeper into the soil.

She noted carbon loss from cultivated fields might be more obvious if they were measuring runoff from a field, since tilled fields have more runoff.

In a recorded message to attendees, Rattan Lal, director of the Carbon Management and Sequestration Center, said working with farmers, the private sector and policy makers to apply research about farm management and carbon is important. If carbon markets grow and more farmers are interested in carbon as a commodity, it will be important to understand how farm practices affect carbon storage.

“Translating science into action is essential,” Lal said. “Otherwise, science has no meaning.”

Nutrients

Total nitrogen levels followed the same pattern as carbon — higher in woodlands and hay fields, and a little bit lower in other fields.

Phosphorus and potassium in the soil weren’t very different across all the different types of farms. The average for phosphorus was 29 parts per million — the recommended level for crop production. The average for potassium was lower than what is recommended, at about 88 parts per million.

Yields

Corn yields had a strong correlation with soil organic matter, but soybean yields did not seem to be connected to organic matter, Bridges said. Soybean yields did have a strong correlation with sulfur. There was also a negative relationship between organic matter and bulk density.

“This just tells us about the relationship between these two things. It doesn’t necessarily mean that they are cause and effect,” Bridges added.

Yields across all farms were higher in 2021 than 2020, but researchers said that was likely because the area got more rain in the summer months in 2021.

Researchers suggested vertical tillage might be a good option for farms in Stark County that have the Canfield silt loam soil type, since it helped farms that used it maintain their yields and soil qualities.

Originally published by The Scientist. Original article available here.

For a little more than a decade, scientists have been filtering water samples from aquariums, rivers, lakes, and even the ocean to obtain DNA that was shed by fish and other aquatic life. The goal: to use this environmental DNA (eDNA) to monitor aquatic species. Now, a trio of papers—two on animals, and one on plants—suggest it’s also possible to detect and identify terrestrial organisms using eDNA floating in the air.

Although the research (along with the entire field of eDNA) is in early stages, experts tell The Scientist that the technology could make it more logistically and financially feasible to find and monitor rare, endangered, invasive, or shy species. Such studies will likely complement rather than replace existing monitoring methods such as camera traps, say scientists working with eDNA, but the ability to fill in the blind spots left by current methods could be immensely beneficial to ecologists.

Genetic analyses including eDNA are “a way of democratizing and enhancing our ability to know what’s going on in the natural world, and also what we’re doing to it,” Mark Stoeckle, an environmental genomicist at the Rockefeller University who uses eDNA to monitor fish populations and was not involved in any of the new studies, tells The Scientist.

Two of the three studies, both published today (January 6) in Current Biology, demonstrated the successful collection and analysis of airborne eDNA shed by animals. Those experiments, one conducted at and around the Hamerton Zoo in the UK and the other at the Copenhagen Zoo in Denmark, relied on the assumption that animals in pens, enclosures, and indoor exhibits would give off strong, consistent signals. The authors of both papers were able to detect and identify the DNA of dozens of different animal species.

By sheer coincidence, the two experiments were conducted in parallel without either team knowing about the other until one team led by York University molecular ecologist Elizabeth Clare, then at Queen Mary University of London, posted its work as a preprint on bioRxiv just days before the other group, led by evolutionary genomicist Kristine Bohmann from the University of Copenhagen’s GLOBE Institute planned to submit its own. After Bohmann’s and first author Christina Lynggaard’s panic over being “scooped” subsided, they tell The Scientist, the two teams got in touch—it’s a small community and they already knew each other—and decided to submit their papers to journals as a package deal. Having “two independent confirmations of the same thing,” Clare tells The Scientist, makes her “feel way more confident that what we’ve done is really replicable.”

York University molecular ecologist Elizabeth Clare collecting airborne eDNA at the Hamerton ZooELIZABETH CLARE

The studies differ in important ways, but their similarities are more prominent. Both captured eDNA using vacuums to pass air through a filter at various sites at their respective zoos. Both used PCR amplification with primers for known species in the area to identify and verify zoo animals, a process called eDNA metabarcoding. And in both cases, their results blew their authors’ expectations out of the water, especially for proof-of-concept research. Based on their findings, the researchers conclude that animal DNA can travel much farther through the air than they expected—both teams were able to detect zoo animals as well as those living outside the zoo, even from hundreds of meters away.

“We were seriously worried it wouldn’t work,” Clare tells The Scientist. Lynggaard echoes that sentiment. “When I was planning this, I thought of the worst-case scenario. . . Most likely we’re not going to get anything,” she says of her initial expectations. But the results were unexpectedly robust, with each sample yielding detectable DNA from between 6 and 21 species.

Altogether, Clare’s team was able to identify DNA from 25 different mammal and bird species that live in or near the zoo, as well as DNA from the food being fed to those animals. Sometimes a sensor located outside of a building would pick up identifiable quantities of DNA from a species housed inside, or from an enclosure located all the way across the zoo. Meanwhile, Bohmann’s team detected 49 vertebrate species: 30 mammals, 13 birds, a handful of fishes, one amphibian, and one reptile—a taxonomic range that left Bohmann and her colleagues “sitting in awe,” she tells The Scientist.

There’s something in the air

The studies follow up on earlier work in which Clare’s team detected airborne eDNA from a colony of naked mole rats maintained in a laboratory setting—an environment with far fewer variables than the zoo.

“The perfect thing about zoos is you have all these nonnative species you cannot mix up with anything else,” Clare tells The Scientist. “And you also know precisely where they are. That became really important for both of us because we were picking up the animals we were near [the sensors], but a lot of other animals as well.”

The zoo research is still considered proof-of-concept for terrestrial eDNA monitoring, though taking the eDNA sensors outdoors represents a notable step forward for the field. In this case, the two teams took a variety of approaches to collection, which the study authors say should be informative as airborne eDNA monitoring makes its way into applied ecological research. Bohmann’s team developed three different types of sensors that sucked in air through both conventional and water vacuums and positioned them in and around the zoo, where they filtered air for hours at a time. By contrast, Clare’s team only used one kind of sensor and ran collections for, at most, half-hour bursts. Having both approaches published side by side, experts tell The Scientist, will serve as a valuable reference when determining which approaches are better for various settings.

“We had forensically-tiny amounts of DNA,” Clare tells The Scientist. “They had tons of DNA,” she adds, but because the other team ran fewer collections for longer periods of time, “they didn’t have as much detail on where it [came from].”

For now, the process is far from perfect. Some animals living in the zoos, such as a tiger that Clare’s team attempted to detect, were missing from the eDNA samples altogether. That might be due to experimental error or the animal shedding less DNA than other creatures, or a combination of myriad other factors. For now, any attempt to explain why some animals were more readily detected than others, Clare says, would be pure speculation.

Two of the air collection devices used by the research team in CopenhagenCHRISTIAN BENDIX

The tiger question also confused Stoeckle, who didn’t work on either of the new papers. He tells The Scientist he would have liked to see more discussion of possible reasons that some animals went undetected, but is overall very complimentary of both zoo studies.

“When you’re starting out, the positive results are the most important ones,” he says. “The negative ones are less important, and the positive results in these papers are great.”

Passively detecting plants

Meanwhile, research on airborne plant eDNA is a few steps ahead, giving animal researchers hints as to what they might attempt next. Last month, Texas Tech University doctoral candidate Mark Johnson, his advisor, ecologist Matthew Barnes’, and their colleagues reported in BMC Ecology and Evolution the results of a study in which they sequenced eDNA from dust traps, which passively collect pollen as well as any other airborne molecules, in a field owned by the university. The team found several species of grass, fungi, and even an invasive species called tree of heaven (Ailanthus altissima) that had all been overlooked by more conventional surveys.

“Airborne eDNA continues to surprise us with how much material is in the environment,” Johnson tells The Scientist.

Johnson and Barnes have conducted similar experiments before, but this paper looked at a year’s worth of collection data, offering new insight into how seasonal changes, weather, and other factors impact the species detected by eDNA, offering new insight into the ecosystem’s dynamics. 

Other researchers are also trying to do the same with insect eDNA. Preprint research presented at last month’s Ecology Across Borders conference reportedly identified 85 insect species—and some vertebrates—from airborne eDNA.

The scientists behind the trio of recent papers all agree that there’s lots of work to be done in order to make eDNA an established and useful tool for ecological research. “We’ve shown that it works, now we need to try to understand some of the nuances of it,” Johnson tells The Scientist. “How does wind, how does weather, how does height affect our collection?”

Leaving the lab

As the field forges ahead, airborne eDNA scientists do have one major source of guidance: the field of aquatic eDNA research, in which researchers have several years’ worth of a head start. Scientists working with aquatic eDNA have already thoroughly demonstrated that the technology works and are now making strides toward using it as a standard ecological tool. Airborne eDNA research is a few years behind, but it’s “following a similar trajectory,” Johnsonexplains.

For both animal and plant studies, the next stage of research involves taking collections out of artificial environments and into natural settings. In some cases, this work is already underway: Johnson is now working on follow-up research in natural environments that takes a closer look at specific variables such as distance, weather, and altitude, and a paper in which he uses his passive dust traps to collect animal eDNA is making its way through the peer review process.

Bohmann, Lynggaard, and Clare note that many basic questions remain unanswered. For example, they won’t be able to glean any sort of temporal resolution—how long ago an animal can pass through the area and still get detected—until they bring their work out of a zoo and into a forest or jungle, where animals roam free rather than being confined to one area. Unfortunately, that kind of research brings new challenges.

“We can’t plug a water vacuum in in the rainforest in Madagascar,” Bohmann tells The Scientist. “And also we can’t make too much noise,” which would disturb the wildlife. That’s why her team tested a few different types of sensors, and why Johnson’s passive collection research will likely prove valuable. “We wanted something that would be transferrable to a natural environment,” Bohmann adds.

University of Guelph biologist Robert Hanner, who didn’t work on any of the studies but helped shape the field of eDNA research, says that the aquatic eDNA research community still has plenty of challenges of its own; although it has progressed further than the airborne eDNA field, scientists don’t yet have all the answers they need to make eDNA surveys practical. For example, ecologists are often interested in measuring the abundance of a given species in an area, and so far, aquatic eDNA surveys only detect their presence.

Airborne eDNA continues to surprise us with how much material is in the environment.—Mark Johnson, Texas Tech University

“There are so many caveats,” Hanner tells The Scientist, adding that the two zoo studies serve as valuable proof-of-concept papers, but that he’s skeptical of their practical utility. Their success “warrants a bit of cautious optimism rather than irrational exuberance,” he says.

Much like Clare’s issue with the zoo’s tiger, Hanner recalls a researcher working in his lab who failed to gather eDNA from a crustacean from water in its immediate vicinity. The challenge, he explains, is that the field doesn’t yet know why that would happen. The conventional explanation would be that the PCR amplification somehow went wrong. But it’s also possible, Hanner says, that certain organisms shed less eDNA than others, or that the primers used to identify them are faulty or can’t handle the degree to which eDNA tends to be fragmented. For all he knows, certain sediments in the water might bind to eDNA or the particles ferrying it, preventing collection of that DNA from happening in the first place.

And that’s just to name a few; Hanner notes that factors such as air or water flow, seasonal changes, time of day, temperature, and, as Johnson examined, altitude, may all play a role in determining how much eDNA is obtained or what species are detected. Yet these details often go unreported in the literature, which has primarily been saturated with proof-of-concept studies focused on showing that eDNA analysis works at all. That, Hanner says, is currently holding the field back.

Still, many researchers are hopeful that eDNA holds the key to understanding what happens in natural environments when scientists are not around to see or hear it.

“It’s surprising how much we don’t know about the natural world, even for familiar animals,” Stoeckle tells The Scientist. “These new technologies are going to help us understand that better, and hopefully be better stewards of the environment. That’s ultimately the goal, and in that way, I’m optimistic.”

Dr. Neil Hammerschlag (featured in this article) was funded by the Herbert W. Hoover Foundation to study shark behavior as discussed in this article. The original article is pasted below.

Originally published by EurekAlert! AAAS. Original article available here.

MIAMI–A new study led by scientists at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science tracked large sharks in Miami and The Bahamas to understand how these migratory animals respond to major storms, like hurricanes.

The researchers analyzed acoustic tag data from tiger sharks (Galeocerdo cuvier), bull sharks (Carcharhinus leucas), nurse sharks (Ginglymostoma cirratum), and great hammerheads (Sphyrna mokarran) before, during, and after Hurricane Matthew in 2016 and Hurricane Irma in 2017. They found that they behaved differently by species and location. 

For example, in response to Hurricane Irma passing by Miami, bull sharks, great hammerhead, and most nurse sharks appeared to mostly evacuate the shallow waters of Biscayne Bay, similar to previous studies that found that small sharks evacuate inshore shallow waters in the wake of a storm. However, large tiger sharks in the Bahamas remained in shallow inshore waters, even as the site received a direct hit from the eye of the category-5 Hurricane Matthew, and immediately following the storm, the number of tiger sharks doubled.

“I was amazed to see that big tiger sharks didn’t evacuate even as the eye of the hurricane was bearing down on them, it was as if they didn’t even flinch.” said Neil Hammerschlag, a research associate professor at the UM Rosenstiel School and the Abess Center for Ecosystem Science and Policy. “their numbers even increased after the storm passed. We suspect tiger sharks were probably taking advantage of all the new scavenging opportunities from dead animals that were churned up in the storm.”

“Major storms, like hurricanes, are predicted to increase in frequency and strength with climate change,” said Hammerschlag, who is also the director of the University’s Shark and Research Conservation Program. “How these storms impact the environment, including large sharks, is of interest and conservation concern to many.”

###

The study, titled “Large sharks exhibit varying behavioral responses to major hurricanes,” was published online May 1 in the journal Estuarine, Coastal and Shelf Science. The study’s authors include: Neil Hammerschlag, Mitchell Rider and Robbie Roemer from the UM Rosenstiel School, Lee Gutowsky from Trent University, Austin Gallagher from Beneath the Waves, Michael Heithaus from Florida International University and Steven Cooke from Carleton University.

The study was funded through grants from the Ocean Tracking Network, the Save Our Seas Foundation, the Disney Conservation Fund, and the Herbert W. Hoover Foundation. The NOAA Cooperative Biscayne Bay HFA project supported maintenance of the acoustic receiver array in Biscayne Bay and logistical boat support was provided by the International Seakeepers Society.

Originally published by EurekAlert! AAAS. Original article available here.

Study finds growing numbers of critically endangered sawfish in Miami waters

The findings have important implications to better protect this endangered species

12/18/20

UNIVERSITY OF MIAMI ROSENSTIEL SCHOOL OF MARINE & ATMOSPHERIC SCIENCE

MIAMI–A new collaborative study lead by scientists at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science and the National Oceanic and Atmospheric Administration (NOAA) found evidence of growing numbers of critically endangered smalltooth sawfish within coastal waters off Miami, Florida, an area where the regular presence of this rare species had gone largely undocumented, until now. The new findings are part of a NOAA initiative to support and enhance the recovery of smalltooth sawfish in and around Biscayne Bay, a coastal lagoon off Miami, that was designated a Habitat Focus Area by NOAA in 2015. 

A shark-like ray, smalltooth sawfish (Pristis pectinata) are unique for their long flat rostra with roughly 22-29 teeth on either side that is used to detect and catch prey. The species can reach 16-feet in length. NOAA estimates that smalltooth sawfish populations in U.S. waters have declined by as much as 95 percent from a combination of overfishing, bycatch in fishing gear, and habitat loss from increasing coastal development.

The research team compiled sighting records dating as far back as 1895 and recent encounters of sawfish in the Biscayne Bay Habitat Focus Area. 

“Our analysis showed sightings have increased exponentially in recent decades, with some individuals even appearing to be making returning annual visits,” said Laura McDonnell, the study’s lead author and a PhD student at UM Abess Center for Ecosystem Science & Policy and researcher at the UM Rosenstiel School. “These findings demonstrate that smalltooth sawfish have been using these waters with some regularity, largely unnoticed prior to the compilation of these records. 

“However, the extent to which sawfish use Biscayne Bay and reason for their occurrence remains unknown,” said Joan Browder, a fisheries biologist at NOAA’s Southeast Fisheries Science Center and senior author of the study. “Understanding this would be a valuable next research step.”

Many of the smalltooth sawfish documented in this study were found in waters very close to Miami, where they were exposed to high levels of pollution, boat traffic, and fishing. 

“These results highlight a need to understand the effects of coastal urbanization on smalltooth sawfish and the conservation implications for this and other endangered species using the area,” said Neil Hammerschlag, research associate professor at the UM Rosenstiel School and UM Abess Center for Ecosystem Science & Policy and co-author of the study. 

“Given the documented use of smalltooth sawfish in and around Biscayne Bay, we hope the area will receive informative signage to help inform the public about their endangered status, the importance of reporting encounters, and the dangers of harming sawfish,” said McDonnell.

###

The researchers urge citizens to report smalltooth sawfish sighting in South Florida waters to 1-844-4-SAWFISH (1-844-472-9347).

The study, titled “Saws and the city: smalltooth sawfish (Pristis pectinata) encounters, recovery potential and research priorities in urbanized coastal waters off Miami, Florida,” was published on December 17, 2020 in the journal Endangered Species Research

The study’s authors include: Neil Hammerschlag and Laura McDonnell at the UM Rosenstiel School, George H. Burgess at the University of Florida; Lindsay Phenix at Northeastern University and Austin J. Gallagher at Beneath the Waves Inc; Thomas Jackson, Helen Albertson and Joan Browder at NOAA’s Southeast Fisheries Science Center in Miami. The collaborative study was conducted as part of the NOAA Cooperative Biscayne Bay Habitat Focus Area project.

Support for this project was provided by the Save Our Seas Foundation, Ocean Tracking Network and the Disney Conservation Fund, Herbert W. Hoover Foundation, NOAA, and C. and M. Jones.

HWHF funded scientist, Dr. Les Kaufman, was recently a guest on the Film the Change podcast where he discussed the importance of coral reef ecosystems and the threats they face. https://www.youtube.com/watch?v=D82ltIp-uwU&t=3629s

By  Paul Greenberg, David Brandt and Lance Nacio 8/4/2020

If it ain’t broke, don’t fix it, goes the saying. Pre-2020, many people who produce this nation’s food might have argued that American agriculture and seafood was anything but broke. On land, the efficient American farmer grows more calories per person than just about any farmer anywhere on earth: U.S. farmers crank out more corn and beef than any nation in the world, are the No. 2 producer of soybeans, and rank in the top four nations for overall tonnage of wheat, pork, and chicken.

At sea, they’re no slouches either. The United States harvests 8 billion pounds of wild fish and shellfish yearly, putting it in a not-too-shabby fourth place globally. All this despite an aging agricultural and fishery workforce that has been losing labor to retirement year after year.

But in 2020, business-as-usual became unusual business. Trade disputes and COVID-driven disruption of international markets flattened sales of core U.S. commodities. This flattening came at a time when corn and soy prices had already dropped sharply off their 2010s highs. Today, American farmers get about half of what they got for a bushel of corn or beans a decade ago.

At sea, too, a tide of problems washed over American food producers in 2020. About 70% of fish in the United States is sold in restaurants. With those markets effectively shuttered, a major disruption rippled its way backward from diner to dock.

All this while, the conditions to farm and fish got tougher. In the last decade, average temperatures in the country’s agricultural heartland rose significantly and precipitation became wild and hard to predict. Meanwhile, at sea, the hypoxia area or dead zone in the continental United States’ most important fishing grounds in the Gulf of Mexico, at the receiving end of most of the nation’s agricultural runoff, grew by more than a third.

Now, as the country tries to find its bearings and producers survey the changed landscape, two seasoned American producers, one on land and one at sea, tell what they think the future holds for American food. Neither is a doomsayer, but both share a belief that a major rethink is in order. With the goal to feed Americans the healthiest food possible, while contributing the most toward profitable agriculture and fisheries, here is a boiled-down version of their thoughts.

LAND

On David Brandt’s farm in Fairfield County, Ohio, in mid-July, the temperature outside is 101°F., but Brandt wasn’t sweating it too hard. His soil temperature is steady at 87°F., while soil on conventional farms in the region roast at a withering 122°F. (Corn tends to shut down and go on the defensive when soil temps top 90°F.)

The reason for this difference, and for Brandt’s overall resilience in the face of 2020’s various crises, is that a long while back he decided to focus on cutting costs rather than boosting harvests. Beginning in 1971, Brandt started shifting his 900 acres from a standard till-and-sow, corn-on-soy rotation to one that puts soil health first.

“Behind corn we plant rye,” he says. “Then comes soy and then small grains and from small grains we go back to corn. We want to loosen that soil. We want our legume crops to catch as much atmospheric nitrogen as possible and put it in the root zone. With the ground covered, we eliminate soil loss to almost zero.”

Brandt does all this cover cropping and soil management not for some hazy hope of helping the environment, but because in the end it’s the best thing for the bottom line. Altogether, the combination of no-till and cover crops saves Brandt something like 60% of his fertilizer and other input costs.

“We are the exception,” Brandt says. “Most farmers are afraid of losing yield. We are not driven by yield – we are driven by cost and return on investment.”

Brandt’s fixation with cost reduction may be the thing that can help lead farmers out of their present quandary. While commodity prices often fall, cost of production nearly always increases. So, as Brandt sees it, even if farmers continue to get better yields out of their lands, the costs, in the end, can easily eat up whatever profits those increased yields might bring.

All of this does indeed bring a tremendous environmental benefit to ecosystems downstream from his farm, and Brandt looks at it as simple common sense.

“It’s in interest to all producers to keep soil on the farm. If we keep filling the Mississippi with sediment, how are we going to ship our crops to market?” Brandt points to the fact that the average Ohio farm loses 3 pounds of soil for every pound of soy beans they produce. “How long can we keep this up?” he asks.

So why aren’t more farmers in Ohio and throughout America’s corn and soy heartland pursuing a cost-saving rather than a yield-boosting strategy?

“It’s not easy to use cover crops,” Brandt explains. “The fields don’t look pretty. Farmers don’t like to see yellow cover crop plants in the field. Or weeds for that matter. For years we’ve been told we could not have one weed in the field and as far as I’m concerned, that’s wrong.”

But Brandt is hopeful that the tide is turning. “The big factor is education. We are getting more and more producers thinking about cover cropping and no-till mainly because the return on investment in business as usual has not been there. Commodities are in the toilet. Guys are strapped. And now, finally we are starting to see a lot of farmers making changes. Even if they just do one cover crop, rye for example – that saves one pass with herbicides.”

And then once they quit using tillage, Brandt adds, they see even more savings in terms of fuel. “The return they’ll see,” Brandt concludes, “is in the fall when they see what’s in the bank.”

SEA 

About 1,100 miles south of David Brandt, Lance Nacio works the northern Gulf of Mexico with two vessels – one outfitted for shrimp, the other targeting reef fish like yellow edge grouper, snapper, and amberjack. Like Brandt, Nacio has been in the food production business for decades.

And like Brandt, Nacio has felt the bite of emphasizing big yields over efficiency. Every year right around this time, a hypoxia area, more commonly known as a dead zone, has been forming in the Gulf. The dead zone forms when water rich in nitrogen from fertilizers triggers algae blooms which in turn die and suck in oxygen when bacteria gobble it up. Last year the Gulf dead zone reached a record size of 6,952 square miles, bigger than the state of Connecticut.

“It’s consistently a problem,” Nacio says. “But last year we were really struggling. The fishing was horrible. The color of the water is the big indicator. When it’s green, that means trouble. Normally we can get out past that green into the blue. But last year everywhere we were going was green. We were really struggling to find places to fish.”

And just like farmers to the north who have huge outlays of cost before a single ear of corn goes through the harvester, Nacio has to put a lot of cash out before a single fish hits the deck. “I have to pay $75,000 to lease quota and then $8,000 on top of that in fish taxes. That’s more than $80,000 right off the top.”

The dead zone makes that off-the-top bite even bigger. “We should be able to shrimp close in. But when the dead zone hugs up against the shore, you can’t find shrimp to save your life. Oftentimes that means we have to make a 20-mile steam out to sea. That definitely adds to cost.” 

True, fishermen got a slight break this past month when hurricane Hanna moved through the Gulf and mixed oxygen into normally hypoxic water, but the 2020 dead zone still ended up bigger than the state of Rhode Island. 

And while Nacio is not one to cast aspersions at his fellow food producers, he increasingly feels exasperated by a situation where the nation seems to rob Peter to pay Paul. He thinks it doesn’t have to be that way.

“If agriculture can minimize the nitrogen runoff and we can get better water out of the Mississippi, it would help prevent the hypoxic zone and would create more life in the gulf. Normally fresh river water is good for the gulf and the health of estuaries. But what we don’t want is hypoxic water. We need fresh water to mix with saltwater – that creates the conditions where things grow. If they could clean the river, it would be a big help.”

But there’s another aspect to this robbing Peter/paying Paul dynamic that Nacio feels needs to be addressed that goes back to the emphasis on yields rather than good ag policy. Because, even as he feels the pinch from dead-zone-induced fisheries damage, Nacio is also crimped by competitors in Asia. Even though the U.S. controls more ocean than any country on earth, something like 80% to 90% of the fish and shellfish Americans eat is coming from abroad. A large portion of that foreign seafood is farmed in Asia. And what do farmers in Asia feed all of that shrimp and fish that they farm? Quite often American soy.

Asian producers further cut costs and make competing difficult by resorting to a number of different strategies that wouldn’t be allowed here in the U.S.

“We really need to level the playing field,” Nacio says. “We need to hold imports accountable. We need to regulate seafood from countries that use slave labor, banned substances, and antibiotics. There was even a story recently where shrimp coming from Ecuador was turned away because the packaging was infected with COVID.”

Speaking of COVID, the pandemic was just one more blow to Nacio’s bottom line. With restaurant orders coming from New Orleans and other big cities nearby grinding to a halt, Nacio has had to rethink distribution, pairing up with other small fishing operations elsewhere in the country to try to offer a direct-to-consumer model.

THE FUTURE

There is no shortage of food in America and no shortage of enthusiasm to bring healthy things to eat to American plates. But both David Brandt and Lance Nacio agree that the current way we’re treating land and sea has to be changed if we’re to get the most benefit for the most Americans. Those changes range from things David Brandt is already doing like using cover crops, limiting tilling, and managing water precisely on his farm.

Changes could also include thinking about what we grow, what we export, and what we import. Do corn and soy have to be the only two crops grown by so many American farmers? Could we start to think about diversifying the agricultural portfolio of the heartland? As temperatures rise, so many more things could be grown in Ohio and elsewhere that currently are deficit items in the American trade portfolio. Fruits, vegetables, and a range of specialty crops could easily work in Midwestern soil.

At sea, do we have to continue to be a seafood debtor, importing so much shrimp and fish from China and the rest of the world? Could we start to treat our home waters better and give American fishermen a leg up in the market so that they could sell their products to their fellow Americans in a fair economic environment?

Could we give American seafood a further helping hand by speeding American fish to the American consumers through new models of distribution and direct-to-consumer methods that Nacio and a few other people are just beginning to employ?

Yes, we can. The hard truth about American food has been laid bare by the multiple crises of 2020. Unfortunately, it is broken. But fortunately, we can fix it.

Published by Successful Farming 8/4/20 https://www.agriculture.com/farm-management/the-future-of-american-food-a-discussion-between-land-and-sea