News and Events
Mushrooms, autumn bloomers in the Mississippi Delta and beyond
Autumn is a time when day length shortens and daytime temperatures begin to decline. These environmental cues induce macrofungi (mushrooms and similar large species) to transition from repeating cycles of asexual reproduction, (through vegetative hyphae and asexual spores), to sexual reproduction. This produces spores capable of overwintering and surviving extreme cold temperatures and harsh conditions.
Pondberry needs light to thrive
Pondberry (Lindera melissifolia) can tolerate deep shade and flooded soil – conditions that would kill many plants. However, the endangered shrub prefers more light and less flooding, as a team of USDA Forest Service researchers led by Ted Leininger shows.
Purified clay needed!
Chase Earles, an award-winning Oklahoma potter, needed clay. The clay could not come from Winterville Mounds but needed to come from somewhere in Washington County, Mississippi.
Barnett Receives Society for Freshwater Science Award
USDA Forest Service fisheries biologist Zanethia Barnett is the winner of the 2022 Society for Freshwater Science (SFS) Hynes Award for New Investigators. The Hynes Award goes to a senior author of an outstanding primary publication within the last three years. Barnett won the award for a 2020 publication in Freshwater Biology that was the first to assess the effects of relatively large dams on crayfish population genetic structure. The publication was based largely on Barnett’s PhD dissertation research, which she received from the University of Mississippi in 2019.
Handbook for 30-year-old Bottomland Oak Stands
Southern floodplain forest landowners can benefit from a new USDA Forest Service handbook of silvicultural practices for oaks planted on former croplands. The practical volume outlines the methods – and supporting science – for managing stands to produce high-quality oak sawtimber, improve wildlife habitat through acorn production, or an integrated approach for both timber and wildlife.
Electrofishing for Crayfish
Since its origin, more than 40,000 years ago, fishing has taken a variety of forms — from spearing to hook-and-line fishing. In the 1960s, scientists began using a method called “electrofishing” to study aquatic populations.
Which Bat Is That? The Smell Will Tell
For the first time, people can distinguish one bat species from another by smell alone. Scientists from the USDA Forest Service and Arkansas State University found that a new, portable electronic nose (e-nose) device is capable of distinguishing between bat species by their smells.
Asian Clams and Native Mussel Growth
Native freshwater mussels grew more slowly when invasive Asian clams (Corbicula fluminea) were abundant. The study was led by Wendell Haag, a USDA Forest Service research fisheries biologist. It was published in the journal Freshwater Biology. Mussels live out of sight – buried in the river bottom, eating algae and other small particles of organic material. Mussels are filter feeders and key members of aquatic ecosystems.
Freshwater Fishes of North America, Volume 2
The highly anticipated second volume of Freshwater Fishes of North America was just published by Johns Hopkins University Press. This volume was edited by USDA Forest Service fisheries research scientist Mel Warren and four other editors. Warren also contributed to seven of the book’s 35 chapters.
Increasingly, recovery plans for imperiled fish species include raising them in captivity and releasing them in the wild. Crystal Ruble of Conservation Fisheries, Inc, with SRS researchers Ken Sterling and Melvin Warren published a protocol for captive propagation of the Yazoo Darter (Etheostoma raneyi). The researchers also summarize its early life-history.
Assessing Surface Water Quality in the Mississippi Delta
USDA Forest Service scientists are measuring surface water quality in the Big Sunflower River watershed of the Mississippi Delta to better understand eutrophication of the Gulf of Mexico. Extensive crop production contributes nutrients and suspended solids and leads to concerns about low dissolved oxygen and pathogens. Ying Ouyang, Ted Leininger, and colleagues monitored water quality for several years at three study sites in the watershed.
E-Noses Detect Emerald Ash Borer Larvae
Electronic noses are sensitive to a vast suite of volatile organic compounds that every living organism emits. A new USDA Forest Service study shows that e-noses can detect emerald ash borer (Agrilus planipennis) larvae lurking under the bark – an early, noninvasive detection method.
Dams and Crayfish Genetics
In Alabama, crayfishes are being separated and genetically changed, which increases the risk of local extinction. This work is not done by a mad scientist, but by dams with their reservoirs and unnatural pools of water. A novel study published in the journal Freshwater Biology by USDA Forest Service scientists Zanethia Barnett and Susan Adams, along with colleagues from the University of Mississippi, covers this phenomenon.
Groundwater Recharge in the Lower Mississippi River Alluvial Valley
The Lower Mississippi River Alluvial Valley is a floodplain that spans seven states. It is suffering from groundwater depletion – a long-term water level decline due to human use. Irrigation and overuse of water resources have led to a seven meter drop in groundwater levels from 1987 to 2014. Water from precipitation and other sources naturally makes its way into groundwater – in a process known as groundwater recharge. Groundwater recharge is known to vary between agricultural and forest land.
Two New Species of Crayfish Discovered in Alabama and Mississippi
In 2011, a group of researchers traveled to southern Alabama and Mississippi in search of the Rusty Gravedigger crayfish (Lacunicambarus miltus). They wanted to refine the species’ range and hoped to find a new population west of Mobile Bay. Instead, they found a potentially undescribed species of crayfish. Years later, a team led by Mael Glon, a Ph.D. candidate at Ohio State University, and USDA Forest Service scientist Susie Adams returned to Mobile Bay in January 2020.
Zanethia Barnett Featured on CAES News
Zanethia Barnett’s alma mater, North Carolina Agricultural and Technical State University, College of Agriculture and Environmental Sciences, has featured her on their website!
Closer to Understanding Enigmatic Mussel Declines
Just by existing and eating, mussels improve water quality. They are filter feeders, which means they eat small pieces of organic matter that float past them. But mussels are dying, often in streams that otherwise seem healthy. Many streams that formerly supported diverse mussel communities now are essentially defaunated. These events are enigmatic because other animals in the streams seem unaffected.
Digging Deep for Crayfish Clues
Kneeling in a wet prairie, arm extended to the armpit in a muddy hole, most biologists would quickly arrive at the thought, “There’s got to be a better way.” So it’s not surprising that, when it comes to sampling for burrowing crayfishes, researchers have devised some creative solutions.