Rappahannock Friends and Lovers of Our Watershed

Volunteers learn to monitor stream quality

By Kit Johnston and Beverly Hunter

Some 20 eager learners, mostly from Rappahannock, Culpeper, and Madison, and several trainers, principally from the Culpeper Soil and Water Conservation District (CSWCD), the Izaak Walton League's Save Our Streams gathered recently on a warm August morning on Cliff Miller's Mount Vernon Farm in Sperryville for a hands-on workshop on how to monitor stream quality.

Leading the workshop was Greg Wichelns, manager for the CSWCD, and Jay Gilliam, who long ago started the League's SOS for western Virginia, in cooperation with scientists from Virginia Tech.

Wichelns provided hand-outs of the Rappahannock River basin and tributary monitoring stations where volunteers who have already received SOS training and certification are performing biological and chemical monitoring. He invited those who received training today to continue until they received their certification so they could help add to the number of stations being monitored. A number of stations in Rappahannock, Madison, and Culpeper are still in need of monitors.

Looking for tiny critters

The focus of the workshop was on how to sample for and identify macro invertebrates-aquatic creatures observable to the naked eye and that have no backbone, which provide one measure of stream health under a scoring system developed by Dr. J. Reese Voshell, Jr., and colleagues at Virginia Tech.

Wichelns demonstrated how to use screens to capture a variety of aquatic life, ranging from worms to leeches to crayfish to snails, clams, and beetles, including "water pennies" and clams and the larvae forms of stoneflies, mayflies, dragonflies, black flies, and so on. Some of these are commonly found in many fresh streams of western Virginia; some are most commonly found only when a stream is clean in terms of chemistry, nutrients, and sediment.

Teams waded into the Thornton River next to Miller's largest barn looking for target "riffles" with underlying cobblestones of a variety of sizes. The objective was to ruffle an area the size of a basketball on the upstream side of the screen for 20 seconds to encourage aquatic life living in and around the cobbles to flow into the screen.

Identifying the capture was a challenge for some first-comers, but they had ID cards and magnifying glasses to help.

One team, composed of a teacher from the Culpeper Christian School, who plans to teach her students to monitor stream quality, Margaret Strawser, a retired CPA from Rappahannock, Beverly Hunter, RappFLOW coordinator, Kit Johnston, a writer from Madison County, and Jay Gilliam captured and identified 65 macro invertebrates in their first sample. Gilliam said that although the objective is to get 200 over a total of four samples, the team had done well and that the river at this point was going to get a high score for biological health.

Another team managed to capture and identify 255 macro invertebrates, and their sample was used to obtain a score for the river at that point on the Thornton River.

The emphasis throughout was on safety for the monitors-including cleansing their hands as soon as possible with, for example, rubbing alcohol — and preserving the health of the captured critters. Teams were advised to count and release larger and more active animals, such as crawfish, very quickly. Any captured minnows and salamanders were to be released immediately, as they are vertebrates. Ice cube trays and spray bottles filled with stream water made it easy to keep relevant animals wetted down and in relative comfort throughout the identification procedure. Once counted, they were released back into the river.

Counting the critters - a good score

While scoring the largest sample obtained that day (255) under Dr. Voshell's system, the number of mayflies, stone flies, and most caddisflies were counted first, then divided by the total sample number, then multiplied by 100. The large sample showed a very healthy percentage of these flies — a very good sign. The percentage in the sample of common net spinners and beetles, as well as lunged snails, was also calculated in this fashion, as well as the number of worms, flat worms, leeches and other invertebrates that are more tolerant of a wide variety of stream conditions.

After a few more straightforward calculations, it was determined that out of a possible top score of 12 for acceptable ecological conditions, the Thornton River at this point on this day rated the top score. The group was reminded that the score does not reflect the presence or absence of bacteria, such as e-coli.

Wichelns promised to stay in touch with all the participants on future workshop and certification opportunities. He and Gilliam, who is now a landscape gardener living outside of Lexington, VA, encouraged anyone truly interested in further observations to build a library of references and field guides. A wealth of further information is available from the SOS web site: www.vasos.org.

©Times Community Newspapers 2005