Year Established: 2014 Start Date: 2014-03-01 End Date: 2016-02-28
Total Federal Funds: $12,000 Total Non-Federal Funds: $24,000
Principal Investigators: J Alford
Abstract: In the Nolichucky River watershed of east Tennessee, there are five fish and seven mussel species listed as endangered or threatened by the State or the U.S. Fish and Wildlife Service, making it one of the most critically important hot spots for North American biodiversity. However, there has been an increase in the conversion of pasture/hay fields into vegetable truck crop agriculture, primarily tomatoes. Tomatoes demand pesticide spray treatments during the warm growing season; subsequently, runoff into tributaries and the Nolichucky main stem occurs. It is thought that pesticide runoff from tomato fields has caused acute fish mortalities in the watershed, one as recent as September 2012. Chronic levels of pesticide toxins may bioaccumulate into tissues of the biota, which can degrade biotic integrity and ecosystem function. The purpose of this project is to assess the influence of land use stressors in the Nolichucky River watershed on (1) bioindicators of population health in representative fish and benthic invertebrate species and (2) the biological integrity of fish and invertebrate communities. The Nolichucky River system will be sampled at 20 reaches during the low-flow, peak growing season (July-September 2014). Physical habitat and in situ water quality will be measured following USEPA Environmental Monitoring and Assessment Protocols (EMAP). Reaches will be stratified, such that 10 are located in the Blue Ridge Mountain ecoregion and 10 in the Ridge and Valley ecoregion. Furthermore, in each ecoregion, 5 sites will be in small reaches (< 8 m wide) and 5 will be in large reaches. Reaches will be further selected along a gradient of land use intensity. Using North Carolina Department of Environment and Natural Resources standard sampling protocols, fish will be sampled with back-pack or boat-mounted electrofishing and seines. Benthic invertebrates (non-unionidae) will be sampled by 500 m-mesh kick nets. Unionid mussels will be sampled by random quadrats and snorkeling. Land use data for each HUC-12 subwatershed will be acquired by remote sensing or aerial photography. Bioindicators of population health will be measured in common fish and mussel species. Fish sampled will be the Tennessee Snubnose darter (Etheostoma simoterum simoterum), Smallmouth bass (Micropterus dolomieu), Central stoneroller (Campostoma anomalum), and/or the Black redhorse (Moxostoma duquesni), assuming enough individuals can be collected (30-50 at each site). To represent mussels, the Rainbow (Villosa iris) will be collected and analyzed. For other benthic invertebrates, densities (no./m2) of Ephemeroptera, Plecoptera, and Trichoptera (EPT) and the Chironomidae will be estimated for each reach. We will investigate the potential use of a new bioindicator of chemical stress in fish. It has been hypothesized that chemical pollution may cause loss of sensory pores and interrupt lateralis system canals in fishes, particularly in the Snubnose darter. This hypothesis has never been tested. We will count pores on the supratemporal, infraorbital, and other lateralis system canals in collections made of Snubnose darters. If we can show a significant decrease in pores and interrupted canals with increasing land use intensity, then this would lead to greater evidence in support of the hypothesis. To assess variation in community structure with respect to land use intensity, a wide variety of indicators of biological integrity (e.g., IBI, multivariate ordination, Indicator Species Analysis) and pollution tolerance indices will be used for fishes, mussels, and benthic invertebrates. The results of this proposed study will help non-governmental conservation groups and state and federal agencies to better monitor the potential impacts of non-point runoff contaminants to aquatic biota in the Nolichucky watershed. In addition, predictive models developed by this research will enable these groups to more efficiently allocate resources and restoration priorities to improving water quality in one of the Nations most historic and ecologically diverse ecosystems.