Cooperative Fish and Wildlife Research Units Program: Tennessee
Education, Research and Technical Assistance for Managing Our Natural Resources

Tennessee Staff Member

Dr. James Layzer

Tennessee Unit Leader Dr. Jim Layzer

Unit Leader
Phone: (931) 372 - 3032


  • Ph D Oklahoma State University 1982
  • MS University of Massachusetts 1974
  • BS University of Massachusetts 1971


BS and MS degrees, University of Massachusetts; PhD, Oklahoma State University. Curently holds the rank of Professor in the Department of Biology and Unit Leader of the Tennessee Unit.

Teaching Interest


Research Interest

Ecology of mussels and restoration of imperiled fish and mussels in regulated rivers. Environmental flows.

Research Publications Publication Date
Weber, A.S. and J.B. Layzer. 2011. A comparison of turtle sampling methods in a small lake in Standing Stone State Park, Overton County, Tennessee. Journal of the Tennessee Academy of Science. 2011-01-31
Strayer, D. L., J. A. Downing, W. R. Haag, T. L. King, J. B. Layzer, T. J. Newton, and S. J. Nichols. 2004. Changing perspectives on pearly mussels, North America's most imperiled animals. Bioscience 54:429-439. 2004-05-31
Simmons, J. W., and J. B. Layzer. 2004. Spawning behavior and habitat of the endangered bluemask darter, Etheostoma (Doration) sp. Copeia 2004(2):412-417. 2004-05-31
Simmons, J. W., J. B. Layzer, and D. D. Smith. 2008. Age-class structure and variability of two populations of the Bluemask darter Etheostoma (Doration) sp. American Midland Naturalist. 160:300-309 2008-05-31
Saha, S., and J. B. Layzer. 2008. Evaluation of a nonlethal technique for determining sex of freshwater mussels. Journal of the North American Benthological Society, 27(1):84-89 2008-03-31
Moles, K. R., and J. B. Layzer 2008. Reproductive ecology of Actinonaias ligamentina (Bivalvia: Unionidae) in a regulated river. Journal of the North American Benthological Society, 27(1):212-222. 2008-01-31
Moles, K. R., N. T. Welte, and J. B. Layzer. 2007. The mussel fauna of the Wolf River, Fentress and Picket Counties, Tennessee. Journal of the Tennessee Academy of Science. 82:77-82. 2007-09-30
Life history of the fluted kidneyshell Ptychobranchus subtentum. American Midland Naturalist 167:79-95. 2012-01-31
Layzer, J. B., and T. R. Brady. 2003. Summer microhabitat of the endangered bluemask darter Etheostoma (Doration) sp. Journal of the Tennessee Academy of Science 78(2):55-57. 2003-10-31
Layzer, J. B., and J. R. Khym. 2005. Fish hosts for glochidia of the pheasantshell (Actinonaias pectorosa). Walkerana. 14(31):79-85. 2005-05-31
Layzer, J. B., and J. R. Heinricher. 2004. Coded wire tag retention in ebonyshell mussels Fusconaia ebena. North American Journal of Fisheries Management 24:228-230. 2004-01-31
Layzer, J. B., B. Adair, S. Saha, and L. M. Woods. 2003. Glochidial hosts and other aspects of the life history of the Cumberland pigtoe (Pleurobema gibberum). Southeastern Naturalist 2(1):73-84. 2003-01-31
Layzer, J. B. 2002. Status of the Freshwater Mussel Fauna in the Green River within the Mammoth Cave National Park - A preliminary Assessment. Pages 51-53 in:9th Mammoth Cave Science Conference, Mammoth Cave, KY. October 10-11. 2002-10-31
Layzer, J. B. 2001. Status of the freshwater mussel fauna in the Green River within Mammoth Cave National Park - A preliminary assessment. Proceedings of the 9th Mammoth Cave Science Conference 2002-09-30
Khym, J. R., and J. B. Layzer. 2000. Host fish suitability for glochidia of Ligumia recta. American Midland Naturalist. 143:178-184 2000-01-31
J. B. Layzer and E. M. Scott, Jr. 2006. Restoration and colonization of freshwater mussels and fish in a southeastern United States tailwater. River Research & Applications. 22:475-491 2006-05-31
Hersey, K.A., J.D. Clark, and J.B. Layzer. Consumption of freshwater bivalves by muskrats in the Green River, Kentucky. 2013-09-30
Hardison, B. S., and J. B. Layzer. 2001. Relations between complex hydraulics and the localized distribution of mussels in three regulated rivers. Regulated Rivers: Research & Management 17:77-84 2001-01-31
Gore, J. A., J. B. Layzer, and J. Mead. 2001. Macroinvertebrate instream flow studies after 20 years; a role in stream management and restoration. Regulated Rivers: Research & Management 17:527-542 2001-09-30
Ehlo, C. A. and J. B. Layzer. Population demographics and life history of the round hickorynut Obovaria subrotunda in the Duck River, Tennessee. American Midland Naturalist. 2013-07-31
Eads, C. B., and J. B. Layzer. 2002. How to pick your mussels out of a crowd: using fluorescence to mark juvenile mussels. J. N. Am. Benthol. Soc. 21:476-486 2002-09-30
Ashton, M.J. and J.B. Layzer. 2010. Summer microhabitat use by adult and young-of-year snail darters (Percina tanasi) in two rivers. Ecology of Freshwater Fish. doi:10.1111/j.1600-0633.2010.00442.x 2010-07-31
Ashton, M., and J. B. Layzer. 2008. Distribution of the threatened snail darter (Percina tanasi) in the upper Tennessee River drainage. Journal of the Tennessee Academy of Science 83:52-56. 2008-07-31
Name Degree Program Status Completion Date
Foley, Ryan Master's Completed Program 2013-12-01
Barton, Stephanie Master's Completed Program 2011-12-01
Ehlo, Chase Master's Completed Program 2011-12-10
Wisniewski, Jason Master's Completed Program 2004-05-01
Welte, Nevin Master's Completed Program 2005-12-17
Weber, Andy Master's Completed Program 2008-05-15
Surgenor, Stacy Master's Completed Program 2003-08-09
Smith, Erin Master's Completed Program 2005-12-17
Simmons, Jeff Master's Completed Program 2004-05-01
Saha, Samrat PhD Completed Program 2007-12-10
Rahm, Eric Master's Completed Program 2008-05-15
Ragland, Dusty Master's Completed Program 2004-05-01
Quinn, Robert Master's Completed Program 2002-08-02
Moles, Kendall PhD Completed Program 2017-12-15
Moles, Kendall Master's Completed Program 2005-12-17
Mengel, Malissa Master's Completed Program 2007-08-10
Helton, Jesse Master's Completed Program 2009-12-10
Ford, Anthony Master's Completed Program 2003-12-10
Farmer, Jason Master's Completed Program 2001-05-11
Ashton, Matt Master's Completed Program 2007-05-10
Adair, Brian Master's Completed Program 2005-08-10
Camp, Mieko PhD Completed Program 2016-08-13
Presentations Presentation Date
Life History of the Cumberland Papershell Anodontoides denigrata. Tyler R. Hern and James B. Layzer. Freshwater Mollusk Conservation Society Symposium. Guntersville, Alabama. 2013-03-11
Kendall R.Moles and James B. Layzer. Reintroduction of mussels into the Calderwood bypass of the Little Tennessee River. A case of fraternizing with the enemy? . Freshwater Mollusk Conservation Society Symposium. Guntersville, Alabama. 2013-03-13
Foley, R. P. and J. B. Layzer. 2013. ANNULUS DEPOSITION AND INTRA-ANNULAR GROWTH OF Epioblasma ahlstedti AND Lemiox rimosus IN THE DUCK RIVER, TENNESSEE. Freshwater Mollusk Conservation Society Symposium. Guntersville, Alabama. 2013-03-11
Technical Publications Publication Date
Smith, E.K., J. Gunderson, and J.B. Layzer. 2006. Gene flow among seemingly isolated populations of the endangered bluemask darter, Etheostoma (Doration) sp. Final Report, Tennessee Wildlife Resources Agency, Nashville, Tennessee. 61pp. 2006-09-30
S.L. Surgenor and J.B. Layzer. 2003. Survival of artificially propagated juvenile mussels. Final Report, Tennessee Wildlife Resources Agency, Nashville, TN. 52pp. 2003-12-31
Martin, R. and J.B. Layzer. 2001. Movements, habitat use, and survival of captive-reared lake sturgeon (Acipenser fulvescens) released into the upper Tennessee river system. Final Report submitted to USGS, Biological Resources Division. 68p 2001-12-31
Layzer, J.B., T.R. Brady, and L.M. Madison. 2002. Propagation of endangered mussels at fish hatcheries. Final Report, U.S. Fish and Wildlife Service. 78pp. 2006-09-30
Layzer, J.B., E.M. Scott, Jr., J.M. Howard, and J.K. Farmer. 2004. Reintroduction of freshwater mussels into the Tennessee River and its major tributaries. Final Report, U.S. Geological Survey, Tennessee Cooperative Fishery Research Unit, Cookeville, Tennessee. 157pp. 2004-01-31
Layzer, J.B., D.L. Ragland, and L.M. Madison. 2004. Reintroduction of endangered mussels and perfection of methods for the establishment of experimental populations. Final Report, Alabama Department of Conservation and Natural Resources. 49pp. 2006-09-30
Layzer, J.B., B. Adair, S. Saha, LM. Woods, and T.R. Brady. 2002. Life history of the Bluemask darter and the Cumberland pigtoe, Phase I: Microhabitats and Host Identification. Final Report submitted to U.S. Fish and Wildlife Service, Cookeville, TN. 31p 2002-06-30
Layzer, J.B. and K. Moles. 2009. Reintroduction of the rayed bean (Villosa fabalis) into the Duck River. U.S. Fish and Wildlife Service. College Station, PA. 2009-09-30
Layzer, J.B. and K. Moles. 2009. Assessment of the fish and mussel communities in the Glenview Nature Preserve on the Green River. Green County, KY. 2009-09-30
Layzer, J.B. and J.W. Simmons. 2004. Structure and stability of bluemask darter populations. Final report, U.S. Fish and Wildlife Service. 60pp. 2006-09-30
Layzer, J.B. 2004. Enhancement of endangered mussels in Horse Lick Creek. Final Report, Kentucky Department of Fish and Wildlife Resources. 15pp. 2006-09-30
Layzer, J.B. 2000. Book Review - Instream flow protection: Seeking a balance in western water use. By D.M. Gillilan and T.C. Brown. Island Press, Washington, DC. 1997. 410pp. In: Fisheries 25(1):42 2001-08-31
Layzer, J.B. 2009. Relationship between stream discharge and recruitment of the Cumberland Elktoe (Alasmidonta atropurpurea). The Nature Conservancy. Tennessee. 2009-09-30
Layzer, J.B. 2004. Recovery of the endangered Ringpink Obovaia retusa. Final Report, U.S. Army Corps of Engineers. 4p. 2006-09-30
Layzer, J.B. 2004. Maintenance of captive populations of endangered freshwater mussels. Final Report, Tennessee Wildlife Resources Agency, Nashville, Tennessee. 5p. 2006-09-30
Brady, T.R., A.L. Currie, and J.B. Layzer. 2003. Development and transfer of technology to propagate and culture mussels at the Dale Hollow and Wolf Creek National Fish Hatcheries. Final Report, U.S. Fish and Wildlife Service, Cookeville, Tennessee. 15pp. 2003-02-28