4290206 Notes of the NorNthOeRNTaHosrEtthAeeSraTnsEte RNrnN aNNatAtuuTrUraaRliAsltiLsIStT, Issue 14/3, 2V10o3l0.( 1174):,3 N9–o4. 23 First Record of Central Stoneroller (Campostoma anomalum) in the Tidal Hudson River Robert E. Schmidt1,*, Richard Morse2, and Bryan Weatherwax2 Abstract - We document the discovery of Campostoma anomalum (Central Stoneroller) in the tidal mouth of the Poestenkill, a Hudson River tributary in Troy, NY. This is the first record of the species from a tidal habitat and is a range extension of approximately 68 km downstream from the Mohawk River. Campostoma anomalum (Rafinesque) (Central Stoneroller) is a small minnow (Cyprinidae) native to the Mississippi Valley and adjacent drainages (Lee et al. 1980 et seq.). This species is known from the Mohawk River (Smith 1985), the largest Hudson River tributary, but there is consensus that the Mohawk River populations are not native (Carlson and Daniels 2004, Schmidt 1986, Smith and Lake 1990). Central stoneroller was not present in the Mohawk River in the 1930s (Smith and Lake 1990) and probably moved through the renovated Barge Canal within the last 40 years (Carlson and Daniels 2004, Daniels 2001). Labidesthes sicculus Cope (Brook Silverside) followed the same route (Marsden et al. 2000) and is now established in the tidal Hudson River (Daniels et al. 2005). The purpose of this paper is to document range expansion of Central Stoneroller to the tidal Hudson River. We collected a single specimen of Central Stoneroller from the Poestenkill in Troy, NY on May 25, 2005 in shallow water (less than 1 m deep) over cobble substrate with a backpack electroshocker. The specimen was measured with a digital calipar to be 46.0 mm SL (NYSM 58486; Fig. 1.) The Poestenkill is the northernmost tributary to the tidal Hudson River. Its mouth is 1.9 km south of the Federal Dam at Troy, the upstream limit of tidal influence. The Central Stoneroller was collected about 20 m downstream (west) of the First Street Bridge in a tidally influenced riffle. Smith (1985) did not list Central Stoneroller from tributaries to the tidal Hudson River, although Carlson and Daniels (2004) indicated that there were records of this species in the area. We sampled the two tributaries (Mill Creek and Moordener Kill, Rensselaer County) where Central Stoneroller was recorded in the 1960s (D. Carlson, NY Department of Environmental Conservation, Waterown, NY, pers. comm.) and found no stoneroller in June 2005. We conclude that these early records were identification errors. This is the first report of this species in tidal water. The tidal Hudson River is completely freshwater in the vicinity of Troy, and brackish water is rarely detected within 145 km of the mouth of the Poestenkill (Cooper et al. 1988). This record is Figure 1. Photograph of a preserved Campostoma anomalum (Central Stoneroller) collected in tidal riffles of the Poestenkill, Troy, NY (NYSM 58486). 492 2007 Notes 493 approximately 42 km downstream of the closest recorded population of Central Stoneroller in the Mohawk River (Smith 1985). Central stoneroller feeds by scraping algae and other organisms from the surface of rocks, usually in flowing water (Smith 1985). There may not be very much habitat for this species in the main Hudson River estuary, but many of the tributary streams would have suitable habitat. Central stoneroller, therefore, has the potential to spread throughout the upper tidal Hudson River system, as it has in the Mohawk River. Smith (1985) said, “The stoneroller is a rather undistinguished minnow….” The best field character is the presence of a hard cartilaginous ridge protruding beyond the lower lip. We urge anyone sampling small fishes in the Hudson River estuary and the upper Hudson watershed to look for this character on otherwise ordinary-looking minnows, perhaps most closely resembling Rhinichthys spp. (Blacknose or Longnose Dace). Central stoneroller joins several species that have invaded the tidal Hudson River from the Mohawk River, probably in this century. Brook Silverside, Moxostoma macrolepidotum (Lesueur) (Shorthead Redhorse), and Aplodinotus grunniens Rafinesque (Freshwater Drum) are now established in the Hudson estuary, although redhorse spawning has not been documented (Schmidt and Lake 2006). Other Mohawk River species may be moving into the Hudson River in the future. Nocomis biguttatus (Kirtland) (Hornyhead Chub), Noturus flavus Rafinesque (Stonecat), Etheostoma flabellare Rafinesque (Fantail Darter), and Etheostoma blennioides Rafinesque (Greenside Darter) are each common in some areas of the Mohawk River, and Noturus miurus (Richardson) (Brindled Madtom) has been collected between the locks in the Barge canal in Waterford (NYSM 51208) and could easily reach the tidal Hudson River. This individual was probably starting its second summer according to sizes reported by Trautman (1957). Since we only caught one specimen, we have little evidence that the species is established. We view this record as a dispersal event and an instance of further homogenization of the Hudson River fish fauna which mimics the larger scale homogenization of fishes in New York (Carlson and Daniels 2004) and North America in general (Rahel 2000). This local homogenization of the fauna is due to human alterations to the watershed and is occurring over the span of decades. It is interesting to note the dispersal of small fishes like the Central Stoneroller. The spread of a small species through a large watershed on a decadal scale has implications for the rapidity of dispersal among watersheds on much longer time scales. Acknowledgments. We thank Gay Malin for helping us with photography. Literature Cited Carlson, D.M., and R.A. Daniels. 2004. Status of fishes in New York: Increases, declines, and homogenization of watersheds. American Midland Naturalist 152:104–139. Cooper, J.C., F.R. Cantelmo, and C.E. Newton. 1988. Overview of the Hudson River estuary. American Fisheries Society Monograph 4:11–24. Daniels, R.A. 2001. Untested assumptions: The role of canals in the dispersal of sea lamprey, alewife, and other fishes in the eastern United States. Environmental Biology of Fishes 60:309–329. Daniels, R.A., K.E. Limburg, R.E. Schmidt, D.L. Strayer, and R.C. Chambers. 2005. Changes in fish assemblages in the tidal Hudson River, New York. Pp. 471–503, In J.N. Rinne, R.M. Hughes, and B. Calamusso (Eds.). Historical Changes in Large River Fish Assemblages of America. American Fisheries Society Symposium 45, Bethesda, MD. 494 Northeastern Naturalist Vol. 14, No. 3 Lee, D.S., C.R. Gilbert, C.H. Hocutt, R.E. Jenkins, D.E. McAllister, and J.R. Stauffer, Jr. (1980 et seq.) Atlas of North American Freshwater Fishes. North Carolina State Museum of Natural History, Raleigh, NC. 854 pp. Marsden, J.E., R.W. Langdon, and S.P. Good. 2000. First occurrence of the Brook Silverside (Labidesthes sicculus) in Lake Champlain, Vermont. Northeastern Naturalist 7:248–254. Rahel, F.J. 2000. Homogenization of fish faunas across the United States. Science 288:854–856. Schmidt, R.E. 1986. Zoogeography of the Northern Appalachians. Pp. 137–159, In C.H. Hocutt and E.O. Wiley. (Eds.). The Zoogeography of North American Freshwater Fishes. John Wiley and Sons, Inc., New York, NY. Schmidt, R.E., and T.R. Lake. 2006. The role of tributaries in the biology of Hudson River fishes. Pp. 205–216, In J. Levinton and J.R. Waldman (Eds.). The Hudson River Estuary. Cambridge University Press, Cambridge, UK. Smith, C.L. 1985. The Inland Fishes of New York State. New York State Department of Environmental Conservation, Albany, NY. 522 pp. Smith, C.L., and T.R. Lake. 1990. Documentation of the Hudson River fish fauna. American Museum Novitates 2981:1–17. Trautman, M.B. 1957. The Fishes of Ohio. The Ohio State University Press, Ames, OH. 683 pp. 1Bard College at Simons Rock, 84 Alford Road, Great Barrington, MA 01230-1978. 2Biological Survey Laboratory 145 Jorddan Road, Troy, NY 12180. *Corresponding author - schmidt@simons-rock.edu.