Leslie Ries

Role: Principal Investigator
Status: Current
Current Affiliation: Georgetown University
Leslie Ries is an ecologist who focuses on patterns at both medium and large scales. She has worked both in the fields of landscape ecology and biogeography with her focus mainly on butterflies. Her current research focuses on large-scale patterns. She explores underlying mechanisms using laboratory studies of caterpillar growth and development based on different temperature regimes. She then studies these patterns across ranges using large databases, mostly originating from citizen science monitoring networks. Citizen science greatly expands the scale at which we can collect data and thus explore problems and solutions that are increasingly global in nature. Ries focuses on several facets of citizen-science, including the use of these data to answer large-scale ecological questions, especially those related to climate and land cover; developing statistical tools to extract the most robust information from the data; designing systems to support data management, visualization, and sharing; and developing “knowledge” databases that compile life history and other trait data to enrich multi-species analyses. In addition to carrying out and enabling large-scale ecological research, Ries has also been working on methods to integrate big-data approaches into undergraduate education, and she is also increasingly interested in informal education opportunities as well.



Farr, M. T., Zylstra, E. R.,Ries, , & Zipkin, E. F. (2024). Overcoming data gaps using integrated models to estimate migratory species' dynamics during cryptic periods of the annual cycle. Methods in Ecology and Evolution

Larsen, E.A., M.W. Belitz, G.J. Di Cecco, J. Glassberg, A.H. Hurlbert, L. Ries and R. P. Guralnick. (In press) Overwintering strategy regulates phenological sensitivity and consequences for ecological services in a clade of temperate North American insects. Functional Ecology

Shirey, V., N. Neupane, R. Guralnick, & L. Ries. (2024). Rising minimum temperatures contribute to 50 years of occupancy decline among cold‐adapted Arctic and boreal butterflies in North America. Global Change Biology, 30(2), e17205.

Abarca, M., Parker, A.L., Larsen, E.A., Umbanhowar, J., Earl, C., Guralnick, R.P., Kingsolver, J., and Ries, L. (2024) How development and survival combine to determine the thermal sensitivity of insects. PLoS ONE 19(1): e0291393. https://doi.org/10.1371/journal.pone.0291393


Di Cecco, G.J., M.W. Belitz, R.J. Cooper, E.A. Larsen*, W.B. Lewis, L. Ries, R.P. Guralnick, and A.H. Hurlbert. (2023) Phenology in adult and larval Lepidoptera from structured and unstructured surveys across eastern North America. Frontiers in Biogeography 15(1).


Neupane, N., M. Peruzzi, A. Arab, S.J. Mayor, J.C. Withey, L. Ries, and A.O. Finley. (2022). A novel model to accurately predict continental-scale timing of forest green-up. International Journal of Applied Earth Observation and Geoinformation. 108: 102747

Larsen, E. A., Belitz, M. W., Guralnick, R. P., & Ries, L. 2022. Consistent Trait-Temperature Interactions Drive Butterfly Phenology in Both Incidental and Survey Data. Scientific Reports, 12(1), 1-10.

Vaughn Shirey, Elise Larsen, Andra Doherty, Clifford A. Kim, Faisal T. Al-Sulaiman, Jomar D. Hinolan, Micael Gabriel A. Itliong, Mark Arcebal K. Naive, Minji Ku, Michael Belitz, Grace Jeschke, Vijay Barve, Gerardo Lamas, Akito Y. Kawahara, Robert Guralnick, Naomi E. Pierce, David J. Lohman, Leslie Ries. (2022) Lep Traits 1.0: Butterfly Traits 1.0: A globally comprehensive dataset of butterfly traits. Scientific Data 9:382

Neupane, N., E. Zipkin, S. Saunders, and L. Ries. 2022. Grappling with uncertainty in ecological projections for the migratory monarch butterfly using tailored climate models. Ecosphere doi.org/10.1002/ecs2.3874


Zylstra, Erin R., Leslie Ries, Naresh Neupane, Sarah P. Saunders, M. Isabel Ramírez, Eduardo Rendón-Salinas, Karen S. Oberhauser, Matthew T. Farr, and Elise F. Zipkin. "Changes in climate drive recent monarch butterfly dynamics." Nature Ecology & Evolution (2021): 1-12.

Mushegian, A., N. Neupane, Z. Batz, M. Mogi, N. Truno, T. Toma, I. Miyagi, L. Ries and P. Armbruster (2021). Letter: Ecological mechanism of climate-mediated selection in a rapidly evolving invasive species. Ecology Letters 24:698-707. doi: 10.1111/ele.13686


Campbell, D., A.Thessen, and L. Ries. 2020. A novel curation system to facilitate data integration across regional citizen science survey programs. PeerJ 8:e9219 https://doi.org/10.7717/peerj.9219

Mainali*, K., T. Hefley, L. Ries, and W.F. Fagan. 2020. Matching expert range maps with species distribution model predictions. Conservation Biology 24:1292-1304.

Belitz, M.W., E.A.Larsen*, L.Ries and R.P. Guralnick. 2020. The accuracy of phenology estimators for use with sparsely sampled presence-only observations. Methods in Ecology and Evolution 11:1273–1285

Bried, J. L. Ries, B. Smith, M. Patten, J. Abbott, J. Ball-Damerow, R. Cannings, A. Cordero-Rivera, A. Córdoba-Aguilar, P. De Marco Jr., K. Dijkstra, A. Dolný, R. van Grunsven, D. Halstead, F. Harabiš, C. Hassall, M. Jeanmougin, C. Jones, L. Juen, V. Kalkman, G. Kietzka, C. Searles Mazzacano, A. Orr, M. Perron, M. Rocha-Ortega, G. Sahlén, M. Samways, A. Siepielski, J. Simaika, F. Suhling, L. Underhill, and E. White. In press. Towards global volunteer monitoring of dragonfly abundance. Bioscience


Wimp, G., L. Ries, D. Lewis, and S. Murphy. In Press. Habitat edge responses of generalist predators are predicted by prey and structural resources. Ecology

Saunders, S.P., L. Ries, N. Neupane, M. I. Ramirez, E.Garcia-Serrano, E. Rendon-Salinas, E.F. Zipkin. 2019. Multi-scale seasonal factors drive the size of winter monarch colonies. Proceedings of the National Academy of Sciences. 201805114

Abarca, M., E.A. Larsen, and L. Ries. (2019). Heatwaves and Novel Host Consumption Increase Overwinter Mortality of an Imperiled Wetland Butterfly. Front. Ecol. Evol. 7: 193. doi: 10.3389/fevo.

Ries, L., E. Zipkin, R. Guralnick. 2019. Tracking trends in monarch abundance over the 20th century is currently impossible using museum records. Proceedings of the National Academy of Sciences Jul 2019, 116 (28) 13745-13748; DOI: 10.1073/pnas.1904807116

Wepprich T, Adrion JR, Ries L, Wiedmann J, Haddad NM (2019) Butterfly abundance declines over 20 years of systematic monitoring in Ohio, USA. PLoS ONE 14(7): e0216270. https://doi.org/10.1371/journal.pone.0216270


Saunders, S., L. Ries, K. Oberhauser, W. Thogmartin, E. Zipkin. 2018. Local and cross-seasonal effects of climate and land-use on migratory monarch butterflies. Ecography. 41 (2), 278-290

Semmens, J.E. Diffendorfer, K. Bagstad, R. Wiederholt, K. Oberhauser, L. Ries, B. Semmens and J. Goldstein J. Loomis, W.E. Thogmartin, B.J. Mattsson, L.Lopez-Hoffman. Online early. Quantifying ecosystem service flows at multiple scales across the range of a long-distance migratory species. Ecosystem Services ong-distance migratory species. Ecosystem services, 31:255-264.

Fletcher Jr, R. J., Didham, R. K., Banks-Leite, C., Barlow, J., Ewers, R. M., Rosindell, J., ... Ries, L.,...& Melo, F. P. (2018). Is habitat fragmentation good for biodiversity?. Biological Conservation, 226, 9-15.

Abarca, M., E. Larsen, J.T. Lill, M. Weiss, E. Lind, L. Ries. 2018. Inclusion of host quality data improves predictions of herbivore phenology. Entomologia Experimentalis et Applicata 166 (8), 648-660

Ries, L., N. Neupane, K. A. Baum, E. F. Zipkin. (2018). Flying through hurricane central: impacts of hurricanes on migrants with a focus on monarch butterflies. Animal Migration 5(1): 94-103..


Ries, L., S.M. Murphy, G.M. Wimp, R.J. Fletcher. 2017. Closing persistent gaps in knowledge about edge ecology. Invited review in Current Landscape Ecology Reports 2:30-41.

Oberhauser, K., R. Wiederholt, J. E. Diffendorfer, D. Semmens, L. Ries, W. E. Thogmartin, L.A. Lopez‐Hoffman, B. Semmens. 2017. A trans‐national monarch butterfly population model and implications for regional conservation priorities. Ecological Entomology, 42(1), 51-60.


Thorson, J.T., J.N. Ianelli, E.A. Larsen, L. Ries, M.D. Scheuerell, C. Szuwalski, and E.F. Zipkin. 2016. Joint dynamic species distribution models: a tool for community ordination and spatio‐temporal monitoring. Global Ecology and Biogeography.

Saunders, S.P., L. Ries, K.S. Oberhauser, and E.F. Zipkin. 2016. Evaluating confidence in population-level predictions from climate impacts: Summer abundances of the monarch butterfly. Global Ecology and Biogeography 25:1000-1012.

Murphy, S.M., A.H. Battocletti, R.M. Tinghitella, G.M. Wimp, and L. Ries. 2016. Complex community and evolutionary responses to habitat fragmentation and habitat edges: what can we learn from insect science? Invited paper in Current Opinion in Insect Science 14:61-65.

Schmucki R., Pe’er G., Roy D.B., Stefanescu C., van Swaay C.A.M., Oliver T.H., Kuussaari M., van Strien A.J., Ries L., Settele J., Musche M., Carnicer J., Schweiger O., Brereton T., Harpke A., Heliola J., Kuhn E., and R. Julliard. 2016. Regionally informed abundance index for supporting integrative analyses across butterfly monitoring schemes. Journal of Applied Ecology. 53:501-510.


Ries, L., E. Rendon and D. Taron. 2015. The disconnect between summer and winter monarch trends for the Eastern migratory population: possible links to differing drivers. Invited paper in Annals of the Entomological Society of America (Online early).

Cayton, H, N. Haddad, K. Gross, S. E. Diamond and L. Ries. 2015. Do growing degree days predict phenology across butterfly species? Ecology 96: 1473–1479

Ries, L. and K. Oberhauser. 2015. A Citizen-Army for Science: Quantifying the Contributions of Citizen Scientists to our Understanding of Monarch Butterfly Biology. Bioscience 65:419-430.

Taron, D. and L. Ries. 2015. Butterfly monitoring for Conservation. Invited book chapter in (J. Daniels, editor) Butterfly Conservation in North America. Springer Press.

Ries, L., K. Oberhauser, D. Taron, E. Rendon-Salinas. 2015. Connecting eastern monarch population dynamics across their migratory cycle. Invited book chapter in (K. Oberhauser, ed.) Monarchs in a changing world: Biology and conservation of an iconic butterfly. Cornell University Press. Ithaca, NY.

Oberhauser, K., L. Ries, S. Altizer, R. Betalden, J. Ekstrum, M. Garland, E. Howard, S. Jepsen, J. Lovett, M. Monroe, G. Morris, E. Rendon, R. RuBino, A. Ryan, C. Taylor, R. Trevino, F. Villablance, D. Walton. 2015. Citizen scientists and an iconic insect: 70 years and counting in (K. Oberhauser, ed.) Monarchs in a changing world: Biology and conservation of an iconic butterfly. Cornell University Press. Ithaca, NY.


Diamond, S.E., H. Lessig*, T. Wepprich, C.N. Jenkins, R.R. Dunn, N.M. Haddad, and L. Ries. 2014. Unexpected phenological responses of butterflies to the interaction of urbanization and geographic temperature. Ecology 95:2613-2621.

Diffendorfer, J.E., J.B. Loomis, L. Ries, K. Oberhauser, L. Lopez-Hoffman, D. Semens, 79B. Semmens, B. Butterfield, K. Bagstad, J. Goldstein, R. Wiederholt, B. Mattsson, and W.E. Thogmartin. 2014. National valuation of monarch butterflies suggests incentive-based conservation strategies could be effective. Conservation Letters 7:253-262.


Butler, L.K., L. Ries, I.A. Bisson, T.J. Hayden, M.M. Wikelski, L.M. Romero. 2013. Opposite but analogous effects of road density on songbirds with contrasting habitat preferences. Animal Conservation 16:77-85


Zipkin, E. F., L. Ries, R. Reeves, J. Regetz and K. S. Oberhauser. 2012. Tracking climate impacts on the migratory monarch butterfly. Global Change Biology 18:3039-3049

Soykan, C.U., L.A. Brand, L. Ries, J.C. Stromberg, C.Hass, D.A.Simmons, Jr., W.J.D. Patterson, J.L. Sabo. 2012. Multitaxonomic diversity patterns along a desert riparian–upland gradient. PLoS ONE 7(1):e28235

Fagan, W. F. and L. Ries. 2012. Edge effects. Berkshire Encyclopedia of Sustainability, Vol. 5: Ecosystem Management and Sustainability. Pp. 118-124.


Koenig, W. D., L. Ries, V.B.K. Olsen*, and A. M. Liebhold. 2011. Avian predators are less abundant during periodical cicada emergences, but why? Ecology 92:784-790.

Wimp, G.M., S.M. Murphy, D. Lewis, L. Ries. 2011. Do edge responses cascade up or down a multi-trophic food web? Ecology Letters 14:863-870


Ries, L. and T. D. Sisk. 2010. What is an 'edge species'? The implications of sensitivity to habitat edges. Oikos 119:1636-1642.


Hannon*, L., L. Ries and K. S. Williams. 2009. Invertebrates of the San Pedro River. Invited book chapter in (J. Stromberg & B. Tellman, eds.) Ecology and Conservation of the San Pedro River. Island Press.


Ries, L. and T. D. Sisk. 2008. Butterfly responses to habitat edges are predicted by a simple model in a complex landscape. Oecologia 156:75-86.

Calabrese*, J. M., L. Ries, S. F. Matter, D. M. Debinski, J. N. Auckland, J. Roland and W. F. Fagan. 2008. Reproductive asynchrony in natural butterfly populations and its consequences for female matelessness. Journal of Animal Ecology 77:746-756.

Ries, L. & S. P. Mullen. 2008. A rare model limits the distribution of its more common mimic: a twist on frequency-dependent Batesian mimicry. Evolution 62:1798-1803.


Fletcher Jr., R. J., L. Ries, J. Battin and A. D. Chalfoun. 2007. The role of habitat area and edge in fragmented landscapes: definitively distinct or inevitably intertwined? Canadian Journal of Zoology 85: 1017-1030.


Ries, L. and T. D. Sisk. 2004. A predictive model of edge effects. Ecology 85:2917-2926.

Ries, L., R. J. Fletcher, J. Battin, and T. D. Sisk. 2004. Ecological responses to habitat edges: mechanisms, models and variability explained. Annual Review of Ecology, Evolution and Systematics 35:491-522.


Ries, L. and W. F. Fagan. 2003. Habitat edges as a potential ecological trap for an insect predator. Ecological Entomology 28:567-572.


Ries, L. and D. M. Debinski. 2001. Butterfly responses to habitat edges in the highly fragmented prairies of central Iowa. Journal of Animal Ecology 70: 840-852.

Ries, L., D. M. Debinski, and M. L. Wieland*. 2001. Conservation value of roadside prairie restoration to butterfly communities. Conservation Biology 15: 401-411.