Clay Nielsen | College of Agricultural Sciences | SIU

Southern Illinois University



Clay Nielsen, Ph.D.

Professor, Forestry

Clay Nielsen

Office Phone: 618 | 453-7474
Building Location: Agriculture Building, 186-C
Curriculum Vitae: Nielsen Long Form CV 2018

Dr. Clay Nielsen is Professor of Wildlife Ecology and Conservation in the Department of Forestry and Cooperative Wildlife Research Laboratory at Southern Illinois University, where he received his Ph.D. in Zoology in 2001. Dr. Nielsen has devoted much of his 25-year research career to wildlife conservation, having conducted research on dozens of primarily mammalian wildlife species in North America, Central America, South America, and the Indian subcontinent.  He has secured >$11 million in funding from myriad sources to support his research program.  Dr. Nielsen has advised >50 graduate students, post-doctoral fellows, and international scholars; and has employed >150 additional technicians to work on his research projects.  He has published >190 scholarly works (including 125 publications in peer-reviewed journals) and given >600 invited lectures and presentations at professional meetings.  Dr. Nielsen's commitment to research and student training was recognized when he was presented the 2014 Outstanding Scholar Award in the College of Agricultural Sciences at SIU.  Beyond SIU, Dr. Nielsen is active with The Wildlife Society as the Past President of both the North Central Section and Illinois State Chapter and is a Certified Wildlife Biologist®.  He also serves as the Director of Scientific Research for the non-profit Cougar Network and is a member of 3 IUCN Species Survival Commission Specialist Groups (Cats, Lagomorphs, and Deer).  Dr. Nielsen’s research has been showcased by hundreds of major media outlets including TIME magazine, the BBC, National Geographic magazine, NPR, the History Channel, and the Discovery Channel.


Ecology, management, and conservation of wildlife; habitat; population dynamics; conflicts between humans and wildlife; urban wildlife; landscape ecology; human dimensions of wildlife


  • FOR 405 - Forest Management for Wildlife
  • FOR 451 - Wildlife Habitat and Populations
  • FOR 494 - Tropical Rainforest Ecology and Conservation
  • FOR 551 - Wildlife-habitat Relationships


  • Ph.D., Zoology, Southern Illinois University Carbondale, 2001
  • M.S., Environmental and Forest Biology, SUNY-ESF, 1996
  • B.S., Natural Resources, University of Nebraska, 1994


  • Schank, C. J. and 31 co-authors including C. K. Nielsen. 2017.  Using a novel model approach to assess the distribution and conservation status of the endangered Baird’s tapir.  Diversity and Distributions 23:1459-1471.
  • Gastal, G. D. A., A. Hamilton, B. G. Alves, S. G. da Silva de Tarso, J. M. N. Feugang, W. J. Banz, G. A. Apgar, C. K. Nielsen, and E. L. Gastal. 2017.  Ovarian features in white-tailed deer (Odocoileus virginianus) fawns and does.  PLoS ONE 12(5): e0177357. doi:10.1371/journal.pone.0177357.
  • Koen, E. L., M. I. Tosa, C. K. Nielsen, and E. M. Schauber. 2017.  Does landscape connectivity shape local and global social network structure in white-tailed deer?  PLoS ONE 12(3): e0173570. doi:10.1371/journal.pone.0173570.
  • Hillard, E. M., C. K. Nielsen, and J. W. Groninger. 2017.  Swamp rabbits as indicators of wildlife habitat quality in bottomland hardwood forest ecosystems.  Ecological Indicators 79:47-53.
  • Pease, B. S., C. K. Nielsen, and E. J. Holzmueller. 2016.  Single-camera trap survey designs miss detections: impacts on estimates of occupancy and community metrics.  PLoS ONE 11(11):e0166689. doi:10.1371/journal.pone.0166689.
  • Shew, J. J., J. van der Merwe, E. M. Schauber, B. A. Caldwell, and C. K. Nielsen. 2016.  A classic question revisited in red-winged blackbirds: disentangling confounding hypotheses surrounding parental investment theory and nest defense intensity.  Behavioral Ecology and Sociobiology 70:1843-1856.
  • Smith, J. B., C. K. Nielsen, and E. C. Hellgren. 2016.  Suitable habitat for recolonizing large carnivores in the midwestern United States.  Oryx 50:555-564.
  • LaRue, M. A., and C. K. Nielsen. 2016.  Population viability of recolonizing cougars in midwestern North America.  Ecological Modelling 321:121-129.