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Donald J. Orth

Headshot of Dr. Donald J. Orth

Headshot of Dr. Donald J. Orth
Office: 106D Cheatham Hall

Ph.D., Oklahoma State University (1980)
M.S., Oklahoma State University (1977) 
B.S., Eastern Illinois University (1975)


I investigate the habitats used by fishes in streams and rivers and develop protocols or habitat suitability criteria for maintaining sustainable populations in the face of various human modifications, such as water withdrawals and habitat modifications.   I also study ecological drivers that influence fish population dynamics and develop and evaluate a variety of instream flow assessment methods in order to derive environmental flows for sustainability.     Finally, I investigate trophic connections between the various food web components to assist in the development of ecosystem based management.

  • NR 1234 First Year Experience in Natural Resources and Environment
  • FiW 4424 Ichthyology
  • FiW 5814 Stream Habitat Management

Management strategy evaluation and economic impact analysis of invasive blue catfish in Virginia tidal rivers.  Y. Jiao, D.J. Orth, and K. Stephenson, Virginia Sea Grant. 2018-2020. $80,000

Commercial production of selected native freshwater ornamental species. E.M. Hallerman, D.J. Orth, and M.H. Schwarz. USDA, NIFA, Southern Regional Aquaculture Center, 2017-2019.  $50,000

Population genetic differentiation of Clinch Dace and barriers to suitable habitats. D.J. Orth and E.M. Hallerman. Virginia Department of Game and Inland Fisheries, 2016-2019. $90,000

Quantifying the trophic impact of non-native blue catfish in Virginia’s tidal rivers. Schmitt, J.D., D.J. Orth, and E.K. Kauffman.  Virginia Sea Grant. 2015-2018. $120,000


  • Brewer, S. K., and D. J. Orth.  2015.  Species conservation profile of the smallmouth bass Micropterus dolomieu.  Pages 9-26 in Tringali et al. Black Bass Diversity: Multidisciplinary Science for Conservation. Proceedings of the Symposium Black Bass Diversity: Multidisciplinary Science for Conservation, American Fisheries Society, Bethesda, Maryland
  • Cooper, P., J.R. Copeland, S.C. Lusk, and D. J. Orth. 2016. Timing of the influence of discharge on recruitment of rock bass in the New River, Virginia. Southeastern Naturalist 15(2):259-268.
  • Dickinson, B.D., S.L. McMullin, J.R. Copeland, and D.J. Orth. 2018. Catch rates, selectivity, and directed effort for setline fishing in the New River, Virginia.  Journal of the Southeastern Association of Fish and Wildlife Agencies 5:46-52.
  • Dickinson, B.D., D.J. Orth, and S.L. McMullin. 2015. Characterizing the human dimensions of a hidden fishery: riverine trotline fishers. Fisheries 40(8):386- 394. 
  • Hatcher, H. M.J. Moore, and D.J. Orth. 2017.  Spawning observations of Clinch Dace in a mountain stream.  The American Midland Naturalist 177:318-326.
  • Hilling, C.D., S.L. Wolf, J.R. Copeland, D.J. Orth, and E.M. Hallerman. 2018. Occurrence of two non-indigenous catostomid fishes in the New River, Virginia.  Southeastern Naturalist 25:215-221. 
  • Hilling, C.D., Y. Jiao, A.J. Bunch, R.S. Greenlee, and D.J. Orth. 2018.  Natural mortality and size-structure of an introduced catfish in Virginia tidal rivers. Journal of the Southeastern Association of Fish and Wildlife Agencies 5:30-38.
  • Grossman, G., D.J. Orth, and J. Neuswanger.  2016.  Innovative Approaches to Fisheries Education and Outreach.  Fisheries 41(8):450-457
  • McManamay, R. A., D. J. Orth, and C. A. Dolloff.  2013.  Application of the ELOHA (Ecological Limits of Hydrologic Alteration) framework to the Cheoah River, a regulated system in the Little Tennessee River basin   Environmental Management.
  • McManamay, R. A., D. J. Orth, J. Kauffman, and M. M. Davis.  2013.  A database and meta-analysis of ecological responses to stream flow in the South Atlantic region.  Southeastern Naturalist 12 (Monograph 5):1-36.
  • Moore, M.J., D.J. Orth, and E.M. Hallerman.  2018. Multi-metric conservation assessment for the imperiled Clinch Dace.   Southeastern Fishes Council Proceedings.  In press.
  • Moore, M.J., D.J. Orth, and E. Frimpong. 2017. Occupancy and detection of Clinch Dace using two gear types. Journal of Fish and Wildlife Management 8(2):530-543.
  • Moore, M.J., E.M. Hallerman, and D.J. Orth. 2017. Densities and population sizes of Clinch Dace Chrosomus sp. cf. saylori in the upper Clinch River Basin in VirginiaCopeia 105(1):92-99.  
  • Moran, Z., D.J. Orth, J.D. Schmitt, E.M. Hallerman, R. Aguilar. 2015. Effectiveness of DNA barcoding for identifying piscine prey items in stomach contents of piscivorous catfishes. Environmental Biology of Fishes 99:161- 167.
  • Orth, D.J.  2018. Social media may empower fisheries students via learning networks.  Fisheries 42(3):130-138 
  • Peoples, B., R. McManamay, D. Orth, and E. Frimpong. 2014.  Spawning habitat use by river chubs in a hydrologically variable Appalachian tailwater.   Ecology of Freshwater Fish 23(2):283-293 
  • Schmitt, J.D., B.K. Peoples, L. Castello, and D.J. Orth. 2018.  Diet, trophic position, and feeding ecology of a generalist consumer: A case study of invasive Blue Catfish Ictalurus furcatus in the Chesapeake Bay.  Environmental Biology of Fishes  
  • Schmitt, J.D., E.M. Hallerman, A. Bunch, Z. Moran, J.A. Emmel, and D.J. Orth. 2017. Predation and prey selectivity by nonnative catfish in an Atlantic slope estuary.  Marine and Coastal Fisheries: Dynamics, Management, and Ecosystem Science 9(1):108-125.  Doi: 10.1080/19425120.2016.1271844
  • Schmitt, J.D., and D.J. Orth. 2015. First record of pughead deformity in Blue Catfish Ictalurus furcatus. Transaction of the American Fisheries Society 144:1111-1116.
  • White, S. L.,  and D. J. Orth.  2014.  Distribution and habitat correlates of Clinch dace (Chrosomus sp. cf. saylori) in the Upper Clinch River watershedThe American Midland Naturalist 171:311-320.