Conservation, Biology, and Natural History of Crayfishes from the Southern US 2010 Southeastern Naturalist 9(Special Issue 3):165–174 Possible Extirpation of Cambarus veteranus (Big Sandy Crayfish) from West Virginia Thomas G. Jones1,*, Katherine B. Channel1, Sean E. Collins1, John Enz2, and C. Michael Stinson3 Abstract - Historical collections and records show that Cambarus veteranus (Big Sandy Crayfish) occurred in 3 West Virginia counties (Logan, Mercer, and Wyoming). The last statewide survey (1988–1989) found C. veteranus only in the Bluestone and Guyandotte river drainages in West Virginia. Competitors for C. veteranus niche space include C. sciotensis (Teays River Crayfish) and other cambarids. Using natural history and previous distributional information, a directed survey was conducted searching 15 probable locations, all at elevations greater than 457 m on the Unglaciated Allegheny Plateau province of WV. These locations included moderately wide streams (>10 m) with permanent pools and having gravel or sand bottoms with large, flat, overlying rocks. Methods included one-hour timed searches using dip net or hand collection of the 15 sampling areas including historical record sites. At each site, water quality data were recorded, and a rapid bioassessment protocol (RBP) score was produced using several physical characteristics. Sampling for this project occurred between June and December 2001. This field survey failed to produce any individuals of C. veteranus. Possible reasons for this included poor water quality, as indicated by low RBP scores, or inadequate sampling. Large-river surveys in West Virginia may produce C. veteranus. Some of the sampled sites may meet criteria for future re-introduction efforts. Introduction Taylor et al. (1996) stressed the crucial need to fully understand the life history and distribution of North American crayfish because of their status as a threatened fauna. A major factor in the decline in biodiversity among North America crayfish is stream endemism, which makes these crayfish especially vulnerable to both watershed degradation and pressure from nonindigenous species (Crandall 1998, Lodge et al. 1998, Taylor et al. 1996). Little is known about the life history or habitat requirements of Cambarus veteranus (Faxon) (Big Sandy Crayfish). Among crayfish in general, it is reported that competition, ontogeny, and land use influence a crayfish’s feeding habits and habitat requirements (Acquistapace et al. 2002, Butler and Stein 1985, Capelli and Munjal 1982, Hill et al. 1993), and habits of crayfish are intricately tied to their environment (Harris 1903). Jezerinac et al.’s (1995) Crayfishes of West Virginia listed C. veteranus habitat as elevation above 457 m in unpolluted streams of moderate 1Marshall University, One John Marshall Drive, Huntington, WV 25701. 2Alderson- Broaddus College, 101 College Hill Drive, Philippi, WV 26416. 3Southside Virginia Community College, 200 Daniel Road, Keysville, VA 23947. *Corresponding author - jonest@marshall.edu. 166 Southeastern Naturalist Vol. 9, Special Issue 3 width (10–20 m) with permanent, fast flowing pools on the Allegheny Plateau. Large flat rocks overlying unconsolidated gravel and sand appeared to be the ideal environment for refuge and burrowing. Historically, habitat degradation may have arisen from high amounts of coal mining, road construction, and ongoing logging within the Allegheny Plateau (Jezerinac et al. 1995). These practices have an effect on water quality, stream structure, and riparian buffers, leading to further habitat degradation (Gray 1996, Swank et al. 2001). Further jeopardy to C. veteranus habitat ensued from effects associated with high flow velocity brought on by floods in 2001 that altered habitat structure, energy sources, and water quality. Unfavorable environments for indigenous species allows for competition and displacement by invasive species (Allison et al. 1992, France and Collins 1993, Hill and Lodge 1999). It has been speculated that a particular threat to C. veteranus included competition with other crayfish species. Jezerinac et al. (1995) believed that the presence of C. sciotensis Rhoades (Teays River Crayfish) and C. robustus Girard (Big Water Crayfish) may have a negative impact on C. veteranus populations as a result of competition. Jezerinac et al. (1995) described C. veteranus as a crayfish with chestnut to greenish brown pigment on the dorsal and lateral body surfaces and with a cream colored venter. The base of the chela and dorsal dactyl knob are red. The triad of a strong cervical spine, no suborbital angle, and 2 rows of tubercles on the mesial margin of the palm constitute the main identifying characteristics for C. veteranus. A statewide survey of West Virginia crayfishes was conducted in 1988 and 1989 (Jezerinac et al. 1995). Of particular interest was that C. veteranus marginally inhabited only 3 river drainages: the Bluestone and Guyandotte in West Virginia; the Big Sandy in Kentucky and Virginia; and the Russell Fork drainage in Virginia (Jezerinac et al. 1995). Cambarus veteranus was first described in 1914 from Indian Creek in the upper Guyandotte River drainage in Wyoming County, WV (Faxon 1914). Jezerinac et al. (1995) recorded only 7 occurrences in Kentucky, 8 in Virginia, and 16 in West Virginia, with low numbers of individuals documented at each site. The 16 West Virginia occurrences were restricted to Wyoming, Mercer, and Logan counties. In 1989, 8 occurrences of C. veteranus produced only 49 individuals from Huff, Pinnacle, and Indian creeks in Logan and Wyoming counties. Historical records of this species included 2 occurrences from 1900 (one of which was the only record for Mercer County and the Bluestone River drainage), 4 from 1947, 1 in 1953 and 1 from 1971. The 51 surveys made during 1988–1989 in Mercer, McDowell, Mingo, Logan, Boone, and Raleigh counties failed to document C. veteranus (Jezerinac et al. 1995). None were found statewide in 1988. The most recent survey for C. veteranus was in the upper Guyandotte basin, WV, 1989 (Jezerinac et al. 1995). The purpose of this study was to conduct crayfish surveys at historical locations with suitable habitat for C. veteranus in Logan, Wyoming, and Mercer counties, WV, and to update the status of C. veteranus in West 2010 T.G. Jones, K.B. Channel, S.E. Collins, J. Enz, and C.M. Stinson 167 Virginia. Historically suitable habitat was defined by means of literature and historical data review. The identification of suitable habitat prior to field surveys would reduce search effort and time expenditure in a sizeable area by focusing the search to the “most likely” locations. The objective was to determine the current distribution of C. veteranus in the upper Guyandotte River drainage. Ground verification of regions identified as suitable habitat would allow the possibility of future reintroduction studies. Study Area The study area was characterized by steep hills and narrow valleys dissected by stream erosion where knolls and rocky layers are evident. The upper Guyandotte watershed is 2183 km2 and contains approximately 2200 km of stream. Elevation ranges from approximately 199–1066 m. Geologic features include bedrock, shale, sandstone, and conglomerate. Forest, coal, and gas make this a region rich in natural resources. Historical data were used to identify and develop suitability maps that met the habitat criteria described by Jezerinac et al. (1995) from which to narrow the search for C. veteranus. Large flat rocks overlying unconsolidated gravel and sand appeared to be the ideal environment for C. veteranus to take refuge and burrow in (Jezerinac et al. 1995). Suitable habitat was in streams located at an altitude greater than 457 m on the Unglaciated Allegheny Plateau. Jezerinac et al. (1995) suggested that C. veteranus would be located in permanent pools with fast-flowing water in streams estimated to be between 10–20 m wide. Cambarus veteranus was not found in suitable habitat areas with water quality degraded by coal fines, septic tank outflows, or containing clay and silt substrate (Jezerinac et al. 1995). These degraded streams were often inhabited by C. robustus, C. sciotensis, and Orconectes species (Jezerinac et al. 1995). Sites from historical records and those regarded as suitable habitat are shown (Table 1, Fig. 1). Methods Between June and December 2001, a two-person team collected crayfish at the selected locations. One individual overturned rocks into the current while the second individual captured retreating crayfish by hand or with a 20-cm dip net (≤1.6-cm2 mesh). Often crayfish buried themselves at the crevice of the rock and substrate interface. To ensure that all crayfish were captured, this interface was searched by tactile methods. Each site was searched for a time interval of about 1 hour. Since species identification was done by morphological traits of the first-form male, special effort was made to obtain a representative male (form I) of all species present. Sex, reproductive status, and other biological information were recorded for each individual crayfish found. Identifications were made using Hobbs (1972) and Jezerinac et al. (1995). 168 Southeastern Naturalist Vol. 9, Special Issue 3 The presence or absence of other species was noted in each stream to determine competitive and/or invasive pressures on C. veteranus. The numbers of C. robustus and C. sciotensis encountered were recorded. Collected field specimens of voucher species were then transferred to a glass jar containing 95% ethanol. Prior to final preservation in the lab with 70% ethanol, photographs were taken of each specimen against a background containing a known measurement scale, using an Olympus Z4000 or comparable digital camera. Camera settings were set to automatic exposure with an image Figure 1. Historical locations of Cambarus veteranus found by Jezerinac et al. (1995) in the upper Guyandotte River basin, WV. All sites except Little Huff Creek were searched again in 2001. 2010 T.G. Jones, K.B. Channel, S.E. Collins, J. Enz, and C.M. Stinson 169 resolution from 3.2–5 megapixels. Images were then downloaded into a PCcompatible computer for a digital archive. Habitat assessments dealt with qualitative physical and chemical factors, water chemistry, predominant surrounding land use, and in-stream characterization (Barbour et al. 1999). Data were logged on the EPA’s Physical Characterization/Water Quality Sheet and Habitat Assessment Field Data Sheet-High Gradient Streams (Barbour et al. 1999). Weather conditions were noted on the day of sampling as well as the conditions for the preceding 7 days. Predominant surrounding land use and stream origin were determined from 1998 digital ortho-quandrangle, 2000 gap analysis, and topographic maps. Water-quality descriptions were addressed on habitat forms and quantified by a Hydrolab Quanta®. Measurements included temperature (ºC), pH, dissolved oxygen (DO; mg/L), percent dissolved oxygen (DO %), conductivity (μS), and turbidity (NTU). These data were used to calculate overall rapid biomonitoring protocol (RBP; Barbour et al. 1999) and West Virginia stream condition index scores (WVSCI; Tetra Tech, Inc. 2000) Results A reconnaissance of historical sites was initiated in June 2001 and concluded in December 2001 (Fig. 1). The native stream crayfish assemblage in this region consisted of 5 species: C. sciotensis, C. bartonii cavatus Hay (Appalachian Brook Crayfish), C. robustus, C. veteranus, and O. cristavarius Taylor (Spiny Stream Crayfish). Orconectes sanbornii (Faxon) (Sanborn’s Crayfish), which had been previously collected in the region, was thought to be a bait-bucket introduction (Jezerinac et al. 1995). In 1988–1989, 5 crayfish species (C. sciotensis, C. bartonii cavatus, C. robustus, C. veteranus, and O. cristavarius) were collected in the drainage. In 2001, only C. sciotensis, C. Table 1. Geo-coordinates of historical Cambarus veteranus streams in Logan, Wyoming, and Mercer counties, WV. These sites were surveyed during the 2001 effort. All coordinates presented are within UTM Zone 17 S. Site ID Stream name UTM Easting UTM Northing County Site 1 Crane 474216 4138157 Mercer Site 2 Pinnacle 462421 4150313 Wyoming Site 3 Little Huff 429032 5159588 Wyoming Site 4 Brier 442547 4156651 Wyoming Site 5 Little Indian 447455 4153618 Wyoming Site 6 Little Indian 443387 4157908 Wyoming Site 7 Little Indian 441345 4160186 Wyoming Site 8 Turkey 446037 4161806 Wyoming Site 9 Barkers 467552 4153092 Wyoming Site 10 Still 461806 4159496 Wyoming Site 11 Huff 433773 4176999 Logan Site 12 Huff 434567 4177049 Wyoming Site 13 Huff 443617 4178218 Wyoming Site 14 Huff 439797 4177547 Wyoming Site 15 Huff 439442 4176766 Wyoming 170 Southeastern Naturalist Vol. 9, Special Issue 3 bartonii cavatus, and O. cristavarius were collected. The total number, gender, and reproductive status of crayfishes in the upper Guyandotte River basin in 2001 were recorded, except for O. sciotensis at Site 2, where data were lost (Table 2). Photographs of C. veteranus were also included (Fig. 2). An assessment of habitat quality was accomplished by following the EPA habitat assessment guidelines (Barbour et al. 1999). In this protocol, the maximum RBP score is 200. A high index score indicates more diverse habitat at that location. A score of less than 120 signifies impaired habitat. In addition, the WVSCI is used as an indicator of the biological health of a stream (Tetra Tech, Inc. 2000). For this assessment, macroinvertebrates were collected as per WVSCI and identified (Merritt and Cummins 1984, Peckarsky et al. 1990). A WVSCI is scored as: (1) very good streams = 78–100, (2) good streams = 68–78, (3) gray streams = 60.6–68, (4) fair streams = 45–60.6, and (5) poor streams = 22–45. Any streams that score less than 60.6 are considered impaired (Tetra Tech, Inc. 2000). Hydrolab Quanta® readings revealed a mixture of high conductivities and turbidity among the sites (Table 3). Figure 2. Cambarus veteranus showing individual (top), annulus ventralis (bottom left), rostrum (bottom center), and first-form male gonopods (bottom right). 2010 T.G. Jones, K.B. Channel, S.E. Collins, J. Enz, and C.M. Stinson 171 Table 2. Total number, gender, and reproductive status of crayfish in the upper Guyandotte River watershed, WV, 2001. For specimens, CABA = Cambarus bartonii cavatus, CASC = Cambarus sciotensis, and ORCR = Orconectes cristavarius. Data were lost for Site 2, ORCR. Male Male Site ID Stream name Specimen Total form I form II Female Juvenile Site 1 Crane CABA 10 1 1 3 5 Site 2 Pinnacle CASC 6 3 0 3 0 ORCR 10 - - - - Site 3 Little Huff ORCR 9 0 5 4 0 Site 4 Brier ORCR 15 4 4 7 0 Site 5 Little Indian ORCR 7 3 0 4 0 Site 6 Little Indian ORCR 1 1 0 0 0 Site 7 Little Indian CASC 1 0 0 1 0 ORCR 5 1 1 3 0 Site 8 Crane CASC 3 0 0 2 1 ORCR 1 1 0 0 0 Site 9 Barkers CASC 1 1 0 0 0 Site 10 Still CASC 1 0 0 0 0 ORCR 3 1 2 0 0 Site 11 Huff CASC 3 1 0 2 0 ORCR 2 0 0 2 0 Site 12 Huff CASC 1 0 0 1 0 ORCR 9 5 0 4 0 Site 13 Huff CASC 12 1 0 7 4 ORCR 2 0 0 2 0 Site 14 Huff CASC 7 3 0 2 2 ORCR 3 3 0 0 0 Site 15 Huff CASC 4 2 0 1 0 ORCR 5 4 0 1 0 Table 3. Results of water quality, West Virginia stream condition index (WVSCI) scores, and total EPA rapid bioassessment protocol (RBP) scores from historical sites of Cambarus veteranus in the upper Guyandotte watershed, WV, 2001. Cond. = conductivity. Temp. DO DO Cond. Turbidity WVSCI RBP Site ID Stream (°C) pH (mg/L) (%) (μS) (NTU) score score Site 1 Crane 8.1 7.3 8.6 72.0 0.656 9.1 47.01 100 Site 2 Pinnacle 8.0 8.2 10.1 87.0 0.478 5.5 73.72 139 Site 3 Little Huff 11.0 8.1 10.6 95.1 0.900 4.8 73.86 127 Site 4 Brier 9.5 8.0 9.4 82.4 0.489 2.3 78.79 157 Site 5 Little Indian 10.7 8.1 8.0 73.2 1.191 1.3 47.58 110 Site 6 Little Indian 12.4 8.1 9.7 90.8 0.404 4.9 53.43 75 Site 7 Little Indian 10.3 8.4 10.8 95.9 1.093 0.1 61.60 155 Site 8 Turkey 9.7 7.5 7.7 65.2 0.332 0.7 64.19 118 Site 9 Barkers 6.3 8.3 12.5 98.9 0.490 0.5 80.54 102 Site 10 Still 6.9 8.2 12.3 98.8 0.913 0.0 64.33 163 Site 11 Huff 7.3 8.1 12.7 94.1 0.473 0.0 72.70 161 Site 12 Huff 7.6 7.8 11.8 98.4 0.466 0.0 73.42 142 Site 13 Huff 7.6 10.1 12.1 98.6 0.186 0.3 66.78 110 Site 14 Huff 7.8 8.3 12.2 98.3 0.471 0.0 69.30 107 Site 15 Huff 8.7 8.5 11.9 98.4 0.544 0.0 68.10 121 172 Southeastern Naturalist Vol. 9, Special Issue 3 Discussion The distribution of an animal species is affected by landscape morphology and other environmental variables (Begon et al. 1990, Ricklefs 1979). It was the purpose of this study to explore suitable habitat locations including historical sites for C. veteranus in Logan, Wyoming, and Mercer counties, WV and to report its current distribution. Jezerinac et al. (1995) contained the only detailed information regarding life history and distribution for C. veteranus. This lack of information necessitated a re-investigation of the historical crayfish locations in WV. During this survey, no individuals of C. veteranus were found. Jezerinac et al. (1995) suggested that the presence of C. sciotensis might have a negative impact on C. veteranus populations either by out-competing C. veteranus or filling the available niche. Between the two survey periods, range expansion was noted in the geographic distribution of C. sciotensis, and this expansion overlapped with historical C. veteranus locations (Jezerinac et al. 1995). Ten historical C. veteranus sites contained only one cambarid species, C. sciotensis. Crane Creek-1, Little Huff Creek-3, Brier Creek-4, Little Indian Creek-5, and Little Indian Creek-6 (Table 2) did not yield C. sciotensis or any cambarid species. Thirty-nine C. sciotensis were collected from the remaining sites as compared to 29 specimens from the historical sites in the 1988–1989 statewide survey. It is unclear why C. sciotensis was present in streams once inhabited by C. veteranus. Reasons for the lack of C. veteranus at historical sites are also unclear. Kerans and Karr (1994) suggested that altered habitat and water-quality conditions change community structure. Poor water quality may directly impact the ability of crayfish to inhabit an area. Hobbs and Hall (1974) suggest that alteration of primary production via sewage effluent contributes to hypoxic conditions in low-flow periods and that O. cristavarius and Cambarus species are not found in environments with oxygen less than 6 mg/L. No sites reported values >7.7 mg/L (Table 3). A pH less than 5.5 negatively affects most crayfish species (Holdich 2002). Physiological and metabolic processes are altered in acidic conditions. Calcium carbonate (CaCO3) is the bulk of the exoskeleton and it is considered the most crucial element of the water chemistry for crayfish (Holdich and Lowery 1988). Recorded values for pH were not below 7.3 (Table 3). However, Little Huff Creek-3, Brier Creek-4, Little Indian Creek-5, and Little Indian Creek-6 scored less than 120 on the EPA RBP habitat assessment. The WVSCI scores for Crane-1, Little Indian Creek-5, and Little Indian Creek-6 were less than 60.6 and substantiate the poor RBP scores and lack of cambarids, specifically C. sciotensis and C. veteranus (Table 3). Cambarus veteranus was not found at any of its historical locations in West Virginia, which may be due to the limited search area or the crayfish’s re-location to another area. There remains the possibility that the West Virginia populations of C. veteranus still exist in the larger rivers that have never been adequately sampled. 2010 T.G. Jones, K.B. Channel, S.E. Collins, J. Enz, and C.M. Stinson 173 Acknowledgments The authors would like to thank the West Virginia Division of Natural Resources’ West Virginia Resources Heritage Program for funding this project through the nongame fund. Thanks also to the Nick J. Rahall Appalachian Transportation Institute, Grant # 2005 for funding. Stuart Welsh provided publication support. The publication of this manuscript was supported, in part, by the US Geological Survey Cooperative Research Unit Program, including the West Virginia Cooperative Fish and Wildlife Research Unit. Dr. Tom Jones would like to thank Ray Jezerinac for introducing his “bucket boy” to crayfish. Literature Cited Acquistapace, P., B.A. Hazlett, and F. Gherardi. 2002. Unsuccessful predation and learning of predator cues by crayfish. 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