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Stephen Blake, Ph.D.

Assistant Professor
Biology


Courses Taught

Principles of Biology I and II (BIOL 1240 and 1260); Evolution - BIOL 3010

Education

B.S., Zoology, University of London (Royal Holloway College)

M.S., Resource Management, University of Edinburgh

Ph.D., Ecology, University of Edinburgh

Research Interests

Blake's research straddles the line between applied research for crisis conservation objectives and a more academically driven agenda in which publishing is an important measure of success. The main focus of his research over the last 20 years has been on the movement ecology and conservation of megavertebrates. This theme has targeted two species in particular - forest elephants in the Congo Basin and giant tortoises on the Galapagos Islands.

His forest elephant research developed incrementally from simple beginnings by asking fundamental questions on the abundance, distribution, size of home ranges, long distance migration the environmental factors that shape ranging in order to promote landscape scale conservation around national parks. In parallel, he developed a broader ecological research context that integrated habitat characterization, feeding ecology, migration, and feedbacks that shape the ecosystem engineering role of this iconic, poorly known and imperiled species. The central goal was always to better understand the ecology and conservation status of forest elephants to assist conservation efforts.

In 2008, he left central Africa, moving to the Galapagos Islands where he first sought to answer basic question of whether tortoise migration even occurred and if so, why. One year of GPS telemetry data and field censuses revealed that tortoises displayed a size-biased partial migratory system on Santa Cruz Island, driven primarily by the spatiotemporal distribution of forage. In parallel we were able to contribute to the knowledge on the feeding ecology and ecosystem engineering roles of Galapagos tortoises, before elaborating a conceptual model of tortoise movement dynamics driven by environmental conditions and mediated by life history and physiology. To date we have fitted over 100 telemetry tags to Galapagos tortoises from four different species on three islands to elucidate the mechanisms that govern movement ecology. Again we are guided by a strong conservation motivation and work in complete collaboration with the Galapagos National Park, the Charles Darwin Foundation, the Max Planck Institute for Ornithology, the Institute for Conservation Medicine of the Saint Louis Zoo and others.

Blake collaborates with The Nature Conservancy (TNC) on a prairie restoration initiative in northwest Missouri at the Dunn Ranch. The goal is to better understand the interactions among bison, fire and other management techniques on prairie plant community dynamics. We seek to determine optimal abundance of bison to maximize species and habitat heterogeneity in this small (2 x 2 mile) remnant prairie.

Publications and Media Placements

Tucker, M. A, et al. 2018. Moving in the Anthropocene: Global reductions in terrestrial mammalian movements. Science 359:466-469.

Bastille-Rousseau, G., J. P. Gibbs, K. Campbell, C. B. Yackulic, and S. Blake. 2017a. Ecosystem implications of conserving endemic versus eradicating introduced large herbivores in the Galapagos Archipelago. Biological Conservation 209:1-10.

Bastille-Rousseau, G., J. P. Gibbs, C. B. Yackulic, J. L. Frair, F. Cabrera, L.-P. Rousseau, M. Wikelski, F. Kümmeth, and S. Blake. 2017b. Animal movement in the absence of predation: environmental drivers of movement strategies in a partial migration system. Oikos 126:1004-1019.

Yackulic, C. B., S. Blake, and G. Bastille-Rousseau. 2017. Benefits of the destinations, not costs of the journeys, shape partial migration patterns. Journal of Animal Ecology 86:972-982.

Ellis-Soto, D., S. Blake, A. Soultan, A. Guézou, F. Cabrera, and S. Lötters. 2017. Plant species dispersed by Galapagos tortoises surf the wave of habitat suitability under anthropogenic climate change. PLoS ONE 12:e0181333

Bastille-Rousseau, G., J. R. Potts, C. B. Yackulic, J. L. Frair, E. H. Ellington, and S. Blake. 2016a. Flexible characterization of animal movement pattern using net squared displacement and a latent state model. Movement Ecology 4:1-12.

Bastille-Rousseau, G., C. B. Yackulic, J. L. Frair, F. Cabrera, and S. Blake. 2016b. Allometric and temporal scaling of movement characteristics in Galapagos tortoises. The Journal of animal ecology 85:1171-1181.

Blake, S., A. Guézou, S. L. Deem, C. B. Yackulic, and F. Cabrera. 2015. The dominance of introduced plant species in the diets of migratory Galapagos tortoises increases with elevation on a human-occupied island. Biotropica 47:246-258.

Blake, S., M. Wikelski, F. Cabrera, A. Guezou, M. Silva, E. Sadeghayobi, C. B. Yackulic, and P. Jaramillo. 2012. Seed dispersal by Galápagos tortoises. Journal of Biogeography 39:1961-1972.

Blake, S., C. B. Yackulic, F. Cabrera, W. Tapia, J. P. Gibbs, F. Kummeth, and M. Wikelski. 2013. Vegetation dynamics drive segregation by body size in Galapagos tortoises migrating across altitudinal gradients. Journal of Animal Ecology 82:310-321.

Maisels, F., S. Strindberg, S. Blake, et al. 2013. Devastating Decline of Forest Elephants in Central Africa. PLoS ONE 8.

Laurance, W. F., et al. 2012. Averting biodiversity collapse in tropical forest protected areas. Nature advance online publication.

Blake, S., L. Deem. S, S. Strindberg, F. Maisels, L. Momont, I. Bila-Isla, I. Douglas-Hamilton, W. B. Karesh, and M. D. Kock. 2008. Roadless Wilderness Area Determines Forest Elephant Movements in the Congo Basin. PLoS ONE 3:e3546

Blake, S., S. Strindberg, P. Boudjan, C. Makombo, I. Bila-Isia, O. Ilambu, F. Grossmann, L. Bene-Bene, B. de Semboli, V. Mbenzo, D. S'hwa, R. Bayogo, L. Williamson, M. Fay, J. Hart, and F. Maisels. 2007. Forest Elephant Crisis in the Congo Basin. PLoS Biology 5:e111.