Ryan B. Stephens

My research addresses novel questions at the nexus of animal ecology, fungal ecology, and forestry to better understand how forests function and to inform best management practices.

Mycorrhizal fungi are symbionts that colonize tree roots and are essential for nutrient and water uptake. Similar to pollinators, small mammals consume and disperse the fruiting bodies (truffles) of mycorrhizal fungi, subsequently mediating local fungal diversity and influencing establishment and growth of trees. I use field surveys and experiments, both in the field and greenhouse, to understand: (1) the factors that shape the dietary and functional niches of small mammals; (2) how small mammals influence soil fungal communities and forest regeneration following timber harvests; and (3) the interactions between truffles and small mammals.

Download my CV

Stephens, R. B., A. P. Ouimette, E. A. Hobbie, and R. J. Rowe. 2022. Reevaluating trophic discrimination factors (∆δ¹³C and ∆δ¹⁵N) for diet reconstruction. Ecological Monographs 92:e1525. (Abstract)

Moore, N. B., R. B. Stephens, and R. J. Rowe. 2022. Nutritional and environmental factors influence small mammal seed selection in Northeastern forests. Ecosphere 13:e4036. (PDF)

Borgmann-Winter, B. W., R. B. Stephens, A. W. D’Amato, S. D. Frey, and R. J. Rowe. 2022. Effects of timber harvest on epigeous fungal fruiting patterns and community structure in a northern hardwood ecosystem. Canadian Journal of Forest Research 52:51-58. (Abstract)

Stephens, R. B., S. D. Frey, A. W. D’Amato, and R. J. Rowe. 2021. Functional, temporal, and spatial complementarity in mammal-fungal spore networks enhances mycorrhizal dispersal following forest harvesting. Functional Ecology 35:2072-2083. (Abstract)

Colella J. P., R. B. Stephens, M. L. Campbell, B. A. Kohli, D. J. Parsons, B. S. McLean. 2021. The open-specimen movement. Bioscience 7:405-414. (Abstract)

Stephens, R. B. and R. J. Rowe. 2020. The underappreciated role of rodent generalists in fungal spore-dispersal networks. Ecology 101:e02972. (Abstract)

Stephens, R. B., A. M. Trowbridge, A. P. Ouimette, W. B. Knighton and E. A. Hobbie, P. C. Stoy, and R. J. Rowe. 2020. Signaling from below: rodents select for deeper fruiting truffles with stronger volatile emissions. Ecology 101:e02964. (Abstract)

Ouimette, A. P, S. V. Ollinger, L. C. Lepine, R. B. Stephens, R. J. Rowe, M. A. Vadeboncoeur, S. J. Tumber-Davila, E. A. Hobbie. 2020. Accounting for carbon flux to mycorrhizal fungi may resolve discrepancies in forest carbon budgets. Ecosystems 23:715–729. (Abstract)

Hope, A. G., R. B. Stephens, S. D. Mueller, V.L V. Tkach, J. R. Demboski. 2020. Speciation of North American pygmy shrews (Soricomorpha: Soricidae) supports spatial but not temporal congruence of diversification among boreal species. Biological Journal of the Linnean Society 129:41-60. (Abstract)

Tisell, H. B., A. L. Degrassi, R. B. Stephens, and R. J. Rowe. 2019. Influence of field technique, density, and sex on home range and overlap of the southern red-backed vole (Myodes gapperi). Canadian Journal of Zoology 97:1101- 1108. (Abstract)

Stephens, R. B., E. A. Hobbie, T. D. Lee, and R. J. Rowe. 2019. Pulsed resource availability changes dietary niche breadth and partitioning between generalist rodent consumers. Ecology and Evolution 9:10681-10693. (PDF)

Stephens, R. B., C. B. Burke, N. Woodman, L. B. Poland, and R. J. Rowe. 2018. Skeletal injuries in small mammals: a multispecies assessment of prevalence and location. Journal of Mammalogy 99:486-497 (PDF)

Stephens, R. B., T. J. Remick, M. J. Ducey, and R. J. Rowe. 2017. Drivers of truffle biomass, community composition, and richness among forest types in the northeastern US. Fungal Ecology 29:30-40. (Abstract)

Stephens, R. B., D. J. Hocking, M. Yamasaki, and R. J. Rowe. 2017. Synchrony in small mammal community dynamics across a forested landscape. Ecography 40: 1198–1209. (Abstract)

Castellano, M. A. and R. B. Stephens. 2017. Elaphomyces species (Elaphomycetaceae, Eurotiales) from Bartlett Experimental Forest, New Hampshire, USA. IMA Fungus 8:49-63. (PDF)

Stephens, R. B., K.  H. Karau, C.  J. Yahnke, S. R. Wendt, and R. J. Rowe. 2015. Dead mice can grow – variation of standard external mammal measurements from live and three postmortem body states. Journal of Mammalogy 96:185-193. (PDF)

Stephens R. B. and E. M. Anderson. 2014. Effects of trap type on small mammal richness, diversity, and mortality. Wildlife Society Bulletin 38:619-627. (PDF)

Stephens R. B. and E. M. Anderson. 2014. Habitat associations and assemblages of small mammals in natural plant communities of Wisconsin. Journal of Mammalogy 95:404-420. (PDF)

Stephens R. B., E. M. Anderson, S. R. Wendt, and J. K. Meece. 2014. Field identification of Peromyscus leucopus noveboracensis and P. maniculatus gracilis in Wisconsin from external measurements. The American Midland Naturalist 171:139-146. (PDF)

Woodman, N. and R. B. Stephens. 2010. At the foot of the shrew: manus morphology distinguishes closely-related Cryptotis goodwini and Cryptotis griseoventris (Mammalia, Soricidae) in Central America. Biological Journal of the Linnean Society 99:118-134. (PDF)

Museum specimens document the occurrence of species in space and time and are used by ecologists, morphologists, and conservation biologists among others.

Additionally, study skins and osteological specimens are important for universities and other institutions as teaching aids for learning species identification or morphological structures. Museum collections are analogous to libraries, deriving their value from housing a variety of taxa along with both older specimens and newer acquisitions. However, despite the use of museum specimens in ecological and evolutionary studies, considerably less attention and resources have been devoted to the preparation of voucher specimens. Furthermore, fewer students are trained in the preparation or appreciation of voucher specimens, jeopardizing the future of museums. To this end, I have made it a point to prepare voucher specimens from my own research and train future researchers in the vouchering process.

I have demonstrated the process of museum preparation of birds and mammals to hundreds of students and have trained dozens in the art of mammal specimen preparation at both the University of Wisconsin Stevens Point and the University of New Hampshire. I have also done seminars to train students and staff at the University of Wisconsin Parkside and Yale University (where I am a Yale Peabody Museum of Natural History Curatorial Affiliate). Since 2006 I have deposited over 6,000 mammal specimens and hundreds of truffle specimens in museum collections across the United States. I have also arranged exchanges for museum specimens with no data to build teaching collections at UWSP and UNH. Below is a list of museums that I have deposited specimens in. I have also arranged exchanges for museum specimens with no data to build teaching collections at UWSP and UNH. Below is a list of museums that I have deposited specimens in.

MAMMAL SPECIMENS

• Museum of Southwestern Biology, Albuquerque, NM
• University of Wisconsin – Stevens Point Museum of Natural History, Stevens Point, WI
• National Museum of Natural History, Smithsonian Institution, Washington, D.C.
• Yale Peabody Museum of Natural History, New Haven, CT
• Natural History Museum of Utah, Salt Lake City, UT
• Monte L. Bean Life Science Museum, Provo, UT
• Harvard Museum of Comparative Zoology, Cambridge, MA 
• University of Alaska Museum, Fairbanks, AK
• Oakland Museum of California, Oakland, CA

TRUFFLE SPECIMENS

• Oregon State University Mycological Collection, Corvallis, OR
• University of Florida Herbarium, Gainesville, FL
• National Fungal Collection, Smithsonian Institution, Washington, D.C.

In addition to classroom instruction, I believe that having the opportunity to work on a research project as an undergraduate is essential for developing the skills needed for entering graduate school or a job in the natural resources field.

Accordingly, I have made a point to include dozens of students in the field and lab components of my research. Moreover, I have closely mentored 13 undergraduate students on independent research projects, helping them to define research questions, formalize a study design, write grants to obtain funding, collect and analyze data, and interpret results. These projects have been on a variety of subjects related to small mammal ecology. All students have presented their findings at undergraduate research symposia or national conferences, and five are coauthors on peer reviewed publications.

To date, four of these students are pursing master’s degrees in biology or natural resource subject areas, with three focusing on aspects directly related to the ecology of small mammals. I find the experience of mentoring students and watching them progress to be one of the most rewarding aspects of research.

PUBLICATIONS

Stephens, R. B., C. B. Burke, N. Woodman, L. B. Poland, and R. J. Rowe. 2018. Skeletal injuries in small mammals: a multispecies assessment of prevalence and location. Journal of Mammalogy 99:486-497.

Stephens, R. B., T. J. Remick, M. J. Ducey, and R. J. Rowe. 2017. Drivers of truffle biomass, community composition, and richness among forest types in the northeastern US. Fungal Ecology 29:30-41.

Stephens, R. B., K.  H. Karau, C.  J. Yahnke, S. R. Wendt, and R. J. Rowe. 2015. Dead mice can grow – variation of standard external mammal measurements from live and three postmortem body states. Journal of Mammalogy 96:185-193.

Stephens R. B., E. M. Anderson, S. R. Wendt, and J. K. Meece. 2014. Field identification of Peromyscus leucopus noveboracensisand P. maniculatus gracilisin Wisconsin from external measurements. The American Midland Naturalist 171:139-146.

PRESENTATIONS

Burke, C. B., R. B. Stephens, N. Woodman, and R. J. Rowe. 2016. Skeletal injuries in small mammals: a multi species assessment of injury type and prevalence. 96th Annual Meeting of the American Society of Mammalogists, Minneapolis, MN. (Poster)

Burke, C. B., R. B. Stephens, N. Woodman, and R. J. Rowe. 2016. Skeletal injuries in small mammals: a multi species assessment of injury type and prevalence. University of New Hampshire Undergraduate Research Conference, Durham, NH. (Poster)

Poland, L. B., R. B. Stephens, and R. J. Rowe. 2016. Missing digits in shrews: insights into a secret live. University of New Hampshire Undergraduate Research Conference, Durham, NH. (Poster)

Graves, R., R. B. Stephens, and R. J. Rowe. 2015. Effects of age, density, and seasonality on molt pattern in the mammal genus Peromyscus. University of New Hampshire Undergraduate Research Conference, Durham, NH. (Oral)

Nowick, J., R. B. Stephens, R. J. Rowe, and E. Hobbie. 2015. Do diets of woodland jumping mice and southern red-backed voles differ across forest types? University of New Hampshire Undergraduate Research Conference, Durham, NH. (Poster)

Remick, T. J., R. B. Stephens, and R. J. Rowe. 2015. Truffle Abundance and Mycophagy by Small Mammals in Northern New England Forests. University of New Hampshire Undergraduate Research Conference, Durham, NH. (Poster)

Uccello, A. J., R. B. Stephens, and R. J. Rowe. Variation in truffle consumption by Myodes gapperi between managed and unmanaged forests in northern New Hampshire. 2015. University of New Hampshire Undergraduate Research Conference, Durham, NH. (Poster)

Karau, K. H., R. B. Stephens, C. J. Yahnke, and S. R. Wendt. 2012. Effects of researcher experience and animal disposition on measurement variation in Mus musculus. UWSP College of Letters and Science Undergraduate Research Symposium, Stevens Point, Wisconsin. (Oral)

Karau, K. H., R. B. Stephens, C. J. Yahnke, and S. R. Wendt. 2012. Effects of researcher experience and animal disposition on measurement variation in Mus musculus. UWSP College of Natural Resources Undergraduate Research Symposium, Stevens Point, Wisconsin. (Oral)

Karau, K. H., M. Shirley, and R. B. Stephens. 2012. Re-evaluation of the arctic shrew (Sorex arcticus) and water shrew (Sorex palustris) distribution in Wisconsin. UWSP College of Natural Resources Undergraduate Research Symposium, Stevens Point, Wisconsin. (Poster)

Wendt, S. R., R. B. Stephens, and E. M. Anderson. 2012. Distinguishing Peromyscus leucopus noveboracensis and P. maniculatus gracilis using external field measurements in Wisconsin. Wisconsin Chapter of The Wildlife Society Annual Conference, Wausau, Wisconsin. (Oral)

Wendt, S. R., R. B. Stephens, and E. M. Anderson. 2012. Distinguishing Peromyscus leucopus noveboracensis and P. maniculatus gracilis using external field measurements in Wisconsin. UWSP College of Natural Resources Undergraduate Research Symposium, Stevens Point, Wisconsin. (Oral)

Wendt, S. R., R. B. Stephens, E. M. Anderson, and J. K. Meece. 2012. Distinguishing Peromyscus leucopus noveboracensis and P. maniculatus gracilis using external field measurements in Wisconsin. Posters at the Rotunda, Madison, Wisconsin. (Poster)

Wendt, S. R., R. B. Stephens, and E. M. Anderson. 2011. Effectiveness of pitfall and Sherman live traps for capturing small mammal species. UWSP College of Natural Resources Undergraduate Research Symposium, Stevens Point, Wisconsin. (Oral)**high honors