Perspectives Online

Fins and Pots. Fish farms and nursery pots provide innovative ways for three graduate students to protect the North Carolina environmment. By Anton Zuiker

Charlene Couch, Nathan Bacheler, and Jim Owen are “part of the leadership in the environmental movement.”
Charlene Couch (top-left), Nathan Bacheler (right) and Jim Owen (bottom-left) are "part of the leadership in the environmental movement," says Jane Rogers, managing director of N.C. Beautiful.
(Photos by Daniel Kim and Becky Kirkland)
Once again, N.C. State University graduate students are fishing for ideas – innovations that will make a difference in how North Carolina uses its natural resources. And, for the tenth year in a row, the Governor and Mrs. Dan K. Moore Fellowship to Keep North Carolina Clean and Beautiful has recognized three of those students with grants of $10,000 each.

The fellowship recipients are doctoral students Charlene Couch, Nathan Bacheler and Jim Owen. Couch and Bacheler are literally fishing for their fellowships – both have innovative projects that hold promise for the state’s aquaculture industry. Owen is showing nursery owners how a new potting substance can drastically reduce the water needed to raise plants.

The fellowship is a partnership between N.C. State University and N.C. Beautiful, a nonprofit organization focused on protecting, preserving and enhancing the state’s appearance and educating students and citizens about sustaining the environment. N.C. Beautiful pays half of each fellowship with proceeds from an annual golf and social event. The student’s college or department contributes the other half.

Charlene Couch
Striped bass historically supported one of the largest commercial fishing industries on the Atlantic Coast, but populations plummeted in the mid-1970s. The striped bass markets needed an alternative food fish, and North Carolina responded with it first hybrid striped bass farm in 1986. Striped bass fish farming grew rapidly: By 2000, there were 22 farms in the state, and they supplied 15 percent of the U.S. market for striped bass.

Charlene CouchCharlene Couch, doctoral student of zoology, wants to see that industry grow. Her research explores the genetic underpinnings of growth and performance in striped bass and may provide a superior fish for farm production through selective breeding.

Working from a diverse collection of adult striped bass held at the Pamlico Aquaculture Field Lab, Couch produced thousands of striped bass offspring and reared them in communal ponds and tanks. Using DNA fingerprinting to assign the progeny to their genetic parents, she’s able to determine which fish grow fastest and biggest. Her findings could enable even more industry growth here in North Carolina, as well as lead to a reduction or elimination of the current practice of capturing broodstock from the wild.

“We’re laying the foundation for developing selectively domesticated broodstock for the [hybrid striped bass] industry,” says Couch. “North Carolina is where the industry began, and it’s kind of nice that it’s coming full circle.”

Couch will use the fellowship money to purchase a laptop computer for analyzing the genetic data she’s collected. The award also gave her the long-awaited opportunity to attend a three-day intensive course on fish medicine at N.C. State’s College of Veterinary Medicine and will allow her to present her research findings at scientific meetings.

Nathan Bacheler
Nate Bacheler, meanwhile, is homing in on the state fish, trying to determine who takes more red drum – recreational fishermen, commercial fishermen, cold winter temperatures or the bottlenose dolphins that prey on the fish throughout the state’s coastal waters.

Nathan BachelerThe oldest and largest red drum, he says, can live for 60 years. That makes them particularly vulnerable to fishermen, so state regulations provide a “window limit” in which fishermen can keep red drum that are larger than 18 inches but smaller than 27 inches. But recently it seems that fewer and fewer juvenile red drum make it through that window, meaning there are fewer mature fish to be protected.

As it is, says Bacheler, the recreational fisherman and the commercial fisherman each blame the other for any declines in the numbers of fish. The dolphins get their share of the blame. So does the weather. Who, or what, asks Bacheler, kills more red drum?

Bacheler will use a “combined” method for estimating red drum mortality, pairing high-tech telemetry with traditional floy tagging to determine how many juvenile red drum die of natural causes and how many end up on the dinner table. Bacheler, a second-year Ph.D. student in zoology, will use some of his fellowship money to purchase a wet suit and diving gear. He’ll don those this winter for a dip into the lower Neuse River, where he wants to fasten an array of ultrasonic listening devices. He’ll implant small transmitters into 100 wild juvenile red drum, release them into the river and then monitor their status for the next two years. Transmitters that stop moving but continue to beep will signify a fish that’s died of natural causes – disease, injury or a change in water temperature – while transmitters that race past the last listening device will signify a dolphin’s meal. Any traditional floy tags – tags that include information about the particular fish – that show up in Bacheler’s mailbox will tell him a fisherman took the red drum out of the water.

With that data, Bacheler will estimate red drum mortality rates – which, in turn, will help state officials find ways to help those fish get to old age.

Jim Owen
Jim Owen is out to stop the water from flowing. He wants to save North Carolina nursery owners some 100,000 gallons per acre per growing season, water that normally seeps through the pots, onto the ground and out to sea. His solution: change the growing material in all those nursery pots.

Jim OwenA horticultural science doctoral student, Owen is researching substrate compositions, the material that goes in the bottom of planter pots. The most common substrate composition in North Carolina today includes bark and sand – but no clay, which is the part of soil that helps retain water. When nursery owners water the plants in the pots, most of the water simply drains out and takes much of the phosphorus fertilizer with it.

Adding clay to the nursery substrate, says Owen, may help the potted plants retain more water and lose fewer nutrients. If his hunch works – and it has for the forestry industry in the Netherlands – then nursery owners in the Southeast will see a dramatic reduction in their water usage and a 60 percent savings of phosphorus in the effluent.

Of course, Owen has to prove that possibility. So for 100 straight afternoons this summer, he visited the College’s horticultural field lab at 1 p.m. to measure the moisture levels in his experimental pots. By studying the water-buffering capabilities of the clay-amended substrate, he hopes to show that his plants don’t go into distress as quickly as potted plants in a conventional substrate. Proving that could have an impact on how water is conserved, especially during seasons of drought, he says.

Owen plans to use his fellowship grant to support his travel to Upton, N.Y., to the Department of Energy’s Brookhaven National Laboratory. There he’ll be able to use XANES (X-ray absorption near-edge structure) spectroscopy to determine the type of phosphorus that flows through all those pots.