Just Another Fish Story?
By Dan Cincotta
We've all heard at least one fish story in our lifetime — you know, about “the big fish that got away.” But have you ever heard a story told by the fish? Well, in recent years fish have been telling a story. Not literally, of course, but indirectly when biologists use them to tell us about the water quality and health of a stream.
Since the passage of the Clean Water Act in 1977, agencies such as the Office of Water Resources in the West Virginia Department of Environmental Protection (DEP) have used water chemistry and bottom-dwelling critters, referred to as macro-invertebrates or benthic organisms, to assess the condition of the state's streams. The creatures found living in the substrate of a clean stream are ones sensitive to pollution. When present, they are regarded as indicators of good water quality. For decades, bottom organisms such as mayflies, stoneflies and caddisflies have been the only stream life used to assess the effectiveness of our water laws. Many biologists today, however, believe that it would be more accurate to use two aquatic animal groups to make this determination. The goal of using fish as a second indicator to complement these other data has been pursued for many years.
So how can fish “tell their story?” Well, if a wide variety of fish species are found in a stream and none of them are too abundant, then you probably have a good quality stream. It's only common sense if you think about it — the presence of a “balanced community” tells a biologist the stream is in good shape. For the past two years the author has been conducting surveys in West Virginia streams using fishes to assess stream health in a manner similar to what has been done with bottom-dwelling organisms. This work was recently completed with grant monies acquired from the U.S. Environmental Protection Agency (EPA). The funding came from the Environmental Monitoring and Assessment Program (EMAP). Doing random surveys statewide and eventually predicting the health of all West Virginia streams is one of two important goals of this effort. Of equal importance is identifying the “best of the best” of West Virginia's streams. Once these special waters are identified, all other streams will be compared to them to determine their condition.
What characteristics do the “best of the best” streams have and what do these fantastic streams look like? In reality, people have altered or damaged every stream in some way. Streams that flowed through our state 200 years ago were no doubt better than anything we have today.
Just think for a minute of what we have done to our streams! Acid- and mercury- laden rain falls into them from the sky; acid drains into them from abandoned mines; channels are dredged and moved; trees that keep them cool and stabilize their banks and watersheds are cut down; and herbicides, pesticides and excessive amounts of nutrients and sediment run into them from agricultural fields and other lands. We still dump sewage and industrial pollutants into them.
All this and more are happening today, nearly 30 years after passage of the strongest water law ever to be put in the books – the Clean Water Act. These actions occur everyday in West Virginia and every other state in the union. In spite of all this bad stuff going on, fish and bottom critters “say” some decent streams still exist in our state and elsewhere.
So what conditions do the fish say are necessary to be the best of the best, or just a darn good stream for that matter? Biologists generally agree that water quality and the physical attributes of a stream determine whether it will contain a balanced community. Water quality is largely described by the temperature, dissolved chemicals, and the amounts and kinds of suspended particles in water. The quality of the water may be measured in many ways, but biologists most often collect information on temperature, acidity (pH), dissolved oxygen and alkalinity (amount of lime available to buffer acid). Other values, which measure the levels of sediment, bacteria, nutrients and heavy metals (aluminum and mercury for example) are also often collected.
But water quality alone does not determine the ability of a stream to produce a productive or balanced population of aquatic animals. Successful animal populations also need a place to live, feed, hide and reproduce. This is where the physical attributes come into play. Stream habitats that support good aquatic populations usually have a variety of substrate (sand, gravel, boulders), live and dead vegetation in the water and on the banks (for cover, food and nutrient recycling), flows, gradients, and channel widths and depths. When both the chemistry and physical factors are balanced and in adequate quality and quantity specific to individual species, then a high quality stream results with the potential to maximize biological production and species richness. In other words, you have a best-of-the-best stream.
Who decides which streams are the best? If fish could really talk, then they would probably tell us their preferences for water quality and habitat. In reality, biologists must make the determination indirectly by collecting water quality and physical data at the same location they sample the fish. During the recently completed EMAP project, the author collected water samples at all his survey locations and sent them to a laboratory for analysis. Physical habitat was evaluated by recording information at the stream relative to the substrates, channel dimensions, flows, bank and stream vegetation, and adjacent land use. Once all the data was examined and the community of fishes identified, biologists were able to determine the stream's condition.
Now some people may argue that this is a considerable amount work to determine a stream's health. After all, if game fish are present or if the stream looks pretty, it probably is in good condition — right? Wrong! The old adage that looks can be deceiving is definitely very true when figuring out stream health. For example, the Middle Fork River at Audra State Park in Upshur County is beautiful. However, the river was actually dead until the DEP and DNR recently collaborated to place limestone sand in the headwaters. The limestone neutralized the acid situation and returned the river to reasonably good water quality. The river now supports a healthy population of fish and other stream critters again.
Another situation that is often misunderstood and receives a lot of attention is the presence of woody debris in streams. Many people have the impression that trees that have fallen into a stream are unsightly and will do harm. This naturally occurring process is actually good for streams. Dead trees recycle nutrients when they decay, provide habitat for fishes and invertebrates, and provide food to stream-dwelling creatures. The woody debris fulfills basic life needs for many animals living in the stream. Granted, if it collects near a bridge, a blockage that causes localized flooding or erosion may result. But you must remember that a bridge is a stream alteration that is not natural, and from the fish's point of view, it is a form of “pollution.” In fact, many stream alterations that are called “improvements” may be considered pollution, as they have an unnatural affect on the stream.
Streams are one of West Virginia's most valuable and plentiful natural resources. They are an integral component of our world and play a huge role in supporting a wide variety of life. Their health is important not only to the more than 180 species of fishes and the numerous invertebrate life that call these waters home in our state, but to all of us who appreciate streams for fishing, swimming, drinking, boating or just their awesome beauty. This resource has been tainted over the years, but if we are willing to “listen” to the fish's story, we can perhaps return this renewable resource to its original quality.
Dan Cincotta is a fisheries biologist stationed in Elkins.