Freshwater Mollusk Monitoring in the South Fork Kentucky River System

Freshwater mollusk monitoring in the South Fork Kentucky River system Final Report to Kentucky Department of Fish and Wildlife Resources State and Tribal Wildlife Grants Program Ryan Evans Kentucky Nature Preserves Commission August 2010 List of Tables Table 1. Historical records of freshwater mussels from the South Fork Kentucky............................. 23 Table 2. Freshwater mussels documented during this study - qualitative sampling .......................... 24 Table 3. Summary statistics table - quantitative sampling .................................................................... 25 Table 4. Species detected in quantitative sampling, with relative abundance values .......................... 26 Table 5. Freshwater snails documented during this study..................................................................... 27 Table 6. Summary table of Rapid Bioassessment Protocol (RBP) scores............................................. 28 2 List of Figures Figure 1. Overview map of South Fork Kentucky River watershed..................................................... 29 Figure 2. Ecoregions of South Fork Kentucky River watershed........................................................... 30 Figure 3. Landcover of South Fork Kentucky River watershed ........................................................... 31 Figure 4. Map of sampling sites................................................................................................................ 32 Figure 5. Maps of species from qualitative sampling ............................................................................ 33 Figure 6. Mussel species richness by river mile ...................................................................................... 55 Figure 7. Length-frequency histograms for selected species - qualitative sampling............................ 56 Figure 8. Comparison of length-frequency histograms – qualitative vs quantitative sampling ......... 57 Figure 9. Comparison of Species Richness for the Redbird River - 1995 to present ........................... 59 Figure 10. Mussel assemblages as identified by Cluster Analysis ......................................................... 61 Figure 11. Map of mussel assemblages in South Fork Kentucky River watershed ............................. 62 Figure 12. Species richness of freshwater snails of South Fork Kentucky River watershed .............. 63 3 List of Appendices Appendix 1. List of sampling locations Appendix 2. RBP sheet used in study Appendix 3. Photos of sites from study 4 Abstract The South Fork Kentucky River system is one of the higher quality watersheds remaining in the upper Kentucky River system. Previous freshwater mussel studies indicate many rare species to still be extant. This study was initiated to identify distributional patterns of freshwater mussels and snails, assess physical habitat quality, and examine potential issues relating to quality of mussel assemblages. 25 species of freshwater mussels were located in the study, including 5 state-listed (3 of which are undergoing federal candidate review). One new freshwater mussel basin record was obtained ( Toxolasma parvus ). Fourteen species of freshwater snails were found, none of which are state or federally- listed, but this did include 5 new South Fork Kentucky basin records and 2 new Kentucky River basin records. Recruitment appeared to be limited in headwater areas, excellent in intermediate stretches of the South Fork Kentucky above Booneville, and somewhat depressed in the lower reaches of the river. Statistical analysis indicated three assemblages in the basin organized primarily along a longitudinal gradient. Impaired tributaries appear to be having a negative effect on freshwater mussel densities in the South Fork Kentucky. Examination of long-term stream gauge data did not indicate any significant changes in flows over time. Recent trends with mining and land use threaten the long-term health of this otherwise high-quality system. 5 Introduction Conservation of freshwater mollusks is an area that has received a great deal of attention in the last decade. Recent estimates by Williams et al (1998) indicate that close to 70% of freshwater mussels are imperiled (either listed or in danger of becoming so). Freshwater snails appear to be following the same trend, with over 70% of the national fauna ranked G3 or higher (Johnson et al. , in prep), much of that driven by endemism in the southeastern United States. Resource agencies in many states are beginning to provide resources and attention to freshwater snails. Clearly, with 64 species (39% of Kentucky’s aquatic mollusk fauna) considered to be Extirpated, Special Concern, Threatened or Endangered (KSNPCa) new approaches to aquatic conservation are needed. Managers are beginning to recognize the importance not only of simply protecting high quality habitats through land acquisition and Best Management Practices, but also to consider the significant need to restore stream channels that have been degraded from past human activities. To this end, benchmarks need to be established not only of Kentucky’s faunal composition at a given site (alpha diversity) but also of how species relate to each other (assemblages and communities, or beta diversity) and how those assemblages and communities function together at the landscape level. This is certainly an area of research needed as increasing emphasis on functional stream restoration is happening in Kentucky at a rapid pace. This study was developed with the idea of identifying patterns in habitat quality and impacts to freshwater mollusks, both in terms of species and assemblage distributions, in the South Fork Kentucky River system. The South Fork Kentucky River watershed is one of the most important remaining aquatic biodiversity areas remaining in the Kentucky River system. Within the Kentucky River system, the South Fork is generally regarded today as having some of the best water quality (KWRRI, 2002) although sections of 9 streams are listed as impaired or only partially supporting water quality standards under the US Clean Water Act (KYDOW, 2008). Few published studies exist on the freshwater mollusk fauna of the basin. Cicerello (1996) conducted a study of the freshwater mussel fauna of the mainstem Red Bird River but to date, there has been no other published literature specific to the mollusk fauna of the South Fork system. Initial distributional investigations of the mussel fauna of the Kentucky River system were conducted by Danglade (1922) with more recent studies by Clark (1988), Houp (1980, 1993), and Taylor (1981, 1984). Studies of freshwater snails in the Kentucky River system have been conducted by Branson and Batch (1971, 1981a, 1981b, 1982) and Branson et al (1987). Description of Study Area The watershed covers 1,936 square kilometers over portions of Clay, Owsley, Lee, Leslie, and Knox counties (Figure 1). The mainstem of the South Fork Kentucky River is formed by the confluence of the Red Bird River and Goose Creek in Oneida, Kentucky. 6 Other major tributaries (HUC 11 watersheds) include Sexton Creek and Bullskin Creek and several smaller tributaries enter the mainstem South Fork Kentucky along its length. The South Fork Kentucky is a moderate to steeply incised river that experiences significant elevation drops and cuts through limestone for much of its headwater reaches resulting in exposed bluffs. This also results in the development of frequent heavy riffle sequences and large cobble/boulder/bedrock substrates. The watershed is characterized by moderate groundwater and rapid runoff rates (KWRRI, 2002). The majority of the basin falls with the Dissected Appalachian Plateau of the Central Appalachian Ecoregion, with the extreme lower portion of the basin falling within the Ohio/Kentucky Carboniferous Plateau of the Western Allegheny Plateau Ecoregion (Figure 2). The basin is bordered to the west by the Cumberland Plateau. The basin is generally characterized by narrow ridges and has narrowed to intermediate width valley bottoms. Land cover in the basin is predominately forested (Figure 3). Agriculture in the watershed occurs primarily in the narrow valley bottom floodplains. Predominant agriculture is pastureland (livestock silage), with small amounts of commercial scale tobacco farming in Clay and Owsley counties (Brown, 2008; Clark, 2009). Daniel Boone National Forest owns a large amount of land in the Redbird River watershed (Redbird Ranger District) as well as non-continuous holdings from the confluence of Redbird River and Goose Creek downstream to Hacker Branch. Records from the watershed prior to this study A total of 27 species of freshwater mussels have been reported from the South Fork Kentucky basin (Table 1). The only available records of Cyclonaias tuberculata are from relic shells from Goose Creek and Redbird River, while Truncilla truncata records were only from fresh or relic shells from the mainstem South Fork Kentucky. Goose Creek and Redbird River, major tributaries which lie in the same physiographic region and have a similar drainage area, both have records of 21 species. The mainstem South Fork Kentucky River has prior records for 24 species. Rare Species Given the generally good water quality in the watershed, the South Fork Kentucky system is home to numerous rare aquatic species. Rare mussel species known from the watershed include: • Epioblasma triquetra (Snuffbox) 1, 2, 3 • Fusconaia subrotunda (Longsolid) 1, 2 • Obovaria subrotunda (Round Hickorynut) 2, 3 •

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