Wesley Hochachka

Senior Research Associate


Population Ecology • Citizen Science • Ecological Informatics • Disease Ecology

I work as a research scientist at the Cornell Lab of Ornithology, mostly on studies that aim to identify why bird species live where they do.

Mostly, this work is related to two projects. First, I am part of a multi-university research team looking at the impacts of a bacterial disease on House Finches, where my interests are largely related to identifying the impacts of this disease on the abundance of House Finches across North America.

Second, I am part of the group of data analysts extracting biological insights from the data collected in the citizen-science project eBird: describing species ranges, identifying their habitat associations, describing seasonal changes in distributions, and similar work.


Ph.D., Zoology, University of British Columbia
M.Sc., Zoology, University of Alberta
B.Sc., Zoology, University of Alberta

Recent Publications

Dayer, A. A., P. C. Pototsky, R. J. Hall, D. M. Hawley, T. B. Phillips, D. N. Bonter, A. M. Dietsch, E. Greig, and W. M. Hochachka (2024). Birds are not the only ones impacted by guidance to cease bird feeding. People and Nature 6:20–26.
Hochachka, W. M., V. Ruiz-Gutierrez, and A. Johnston (2023). Considerations for fitting occupancy models to data from eBird and similar volunteer-collected data. Ornithology 140:ukad035.
Fink, D., A. Johnston, M. Strimas‐Mackey, T. Auer, W. M. Hochachka, S. Ligocki, L. Oldham Jaromczyk, O. Robinson, C. Wood, S. Kelling, and A. D. Rodewald (2023). A Double machine learning trend model for citizen science data. Methods in Ecology and Evolution 14:2435–2448.
Miller, E. T., O. Mac Aodha, E. I. Greig, D. N. Bonter, and W. M. Hochachka (2022). Congeneric predators fill discrete niches created by the relative abundances of their prey species. Journal of Avian Biology n/a:e02934.
Robinson, O. J., J. B. Socolar, E. F. Stuber, T. Auer, A. J. Berryman, P. H. Boersch-Supan, D. J. Brightsmith, A. H. Burbidge, S. H. M. Butchart, C. L. Davis, A. M. Dokter, et al. (2022). Extreme uncertainty and unquantifiable bias do not inform population sizes. Proceedings of the National Academy of Sciences 119:e2113862119.
Soultan, A., D. Pavón-Jordán, U. Bradter, B. K. Sandercock, W. M. Hochachka, A. Johnston, J. Brommer, E. Gaget, V. Keller, P. Knaus, K. Aghababyan, et al. (2022). The future distribution of wetland birds breeding in Europe validated against observed changes in distribution. Environmental Research Letters 17:024025.
Bradter, U., A. Johnston, W. M. Hochachka, A. Soultan, J. E. Brommer, E. Gaget, J. A. Kålås, A. Lehikoinen, Å. Lindström, S. Piirainen, D. Pavón‐Jordán, et al. (2022). Decomposing the spatial and temporal effects of climate on bird populations in northern European mountains. Global Change Biology 28:6209–6227.
Hochachka, W. (2022). Project FeederWatch: Zero-filling and taxonomic roll-up. [Online.] Available at
Ng, W. H., D. Fink, F. A. La Sorte, T. Auer, W. M. Hochachka, A. Johnston, and A. M. Dokter (2022). Continental‐scale biomass redistribution by migratory birds in response to seasonal variation in productivity. Global Ecology and Biogeography 31:727–739.
Gorleri, F. C., W. M. Hochachka, and J. I. Areta (2021). Distribution models using semi-structured community science data outperform unstructured-data models for a data-poor species, the Plain Tyrannulet. Ornithological Applications 123:duab038.
Gaget, E., D. Pavón‐Jordán, A. Johnston, A. Lehikoinen, W. M. Hochachka, B. K. Sandercock, A. Soultan, H. Azafzaf, N. Bendjedda, T. Bino, L. Božič, et al. (2021). Benefits of protected areas for nonbreeding waterbirds adjusting their distributions under climate warming. Conservation Biology 35:834–845.
Turbek, S. P., M. Browne, A. S. Di Giacomo, C. Kopuchian, W. M. Hochachka, C. Estalles, D. A. Lijtmaer, P. L. Tubaro, L. F. Silveira, I. J. Lovette, R. J. Safran, et al. (2021). Rapid speciation via the evolution of pre-mating isolation in the Iberá Seedeater. Science 371:eabc0256.
Mady, R. P., M. Hochachka, and D. N. Bonter (2021). Consistency in supplemental food availability affects the space use of wintering birds. Behavioral Ecology 32:580–589.
Hochachka, W. M., H. Alonso, C. Gutiérrez-Expósito, E. Miller, and A. Johnston (2021). Regional variation in the impacts of the COVID-19 pandemic on the quantity and quality of data collected by the project eBird. Biological Conservation 254:108974.
Hochachka, W. M., A. P. Dobson, D. M. Hawley, and A. A. Dhondt (2021). Host population dynamics in the face of an evolving pathogen. Journal of Animal Ecology 90:1480–1491.
Johnston, A., W. M. Hochachka, M. E. Strimas-Mackey, V. Ruiz Gutierrez, O. J. Robinson, E. T. Miller, T. Auer, S. T. Kelling, and D. Fink (2021). Analytical guidelines to increase the value of community science data: An example using eBird data to estimate species distributions. Diversity and Distributions 27:1265–1277.
Fink, D., T. Auer, A. Johnston, V. Ruiz‐Gutierrez, W. M. Hochachka, and S. Kelling (2020). Modeling avian full annual cycle distribution and population trends with citizen science data. Ecological Applications 30:e02056.
Horton, K. G., F. A. La Sorte, D. Sheldon, T.-Y. Lin, K. Winner, G. Bernstein, S. Maji, W. M. Hochachka, and A. Farnsworth (2020). Phenology of nocturnal avian migration has shifted at the continental scale. Nature Climate Change 10:63–68.
Coleman, T., L. Mentch, D. Fink, F. A. La Sorte, D. W. Winkler, G. Hooker, and W. M. Hochachka (2020). Statistical inference on Tree Swallow migration with random forests. Journal of the Royal Society of Statistics: Series C (Applied Statistics) 69:973–989.
Dhondt, A. A., A. P. Dobson, and W. M. Hochachka (2019). Mycoplasmal conjunctivitis in House Finches: The study of an emerging disease. In Wildlife Disease Ecology (K. Wilson, A. Fenton and D. Tompkins, Editors). 1st edition. Cambridge University Press, pp. 574–597.
Dayer, A. A., C. Rosenblatt, D. N. Bonter, H. Faulkner, R. J. Hall, W. M. Hochachka, T. B. Phillips, and D. M. Hawley (2019). Observations at backyard bird feeders influence the emotions and actions of people that feed birds. People and Nature 1:138–151.
Johnston, A., W. Hochachka, M. Strimas-Mackey, V. R. Gutierrez, O. Robinson, E. Miller, T. Auer, S. Kelling, and D. Fink (2019). Best practices for making reliable inferences from citizen science data: Case study using eBird to estimate species distributions. bioRxiv. https://doi.org/10.1101/574392
Kelling, S., A. Johnston, A. Bonn, D. Fink, V. Ruiz-Gutierrez, R. Bonney, M. Fernandez, W. M. Hochachka, R. Julliard, R. Kraemer, and R. Guralnick (2019). Using Semistructured Surveys to Improve Citizen Science Data for Monitoring Biodiversity. BioScience 69:170–179.
Kubizňák, P., W. M. Hochachka, V. Osoba, T. Kotek, J. Kuchař, V. Klapetek, K. Hradcová, J. Růžička, and M. Zárybnická (2019). Designing network‐connected systems for ecological research and education. Ecosphere 10:e02761.
Dhondt, A. A., A. P. Dobson, and W. M. Hochachka (2019). [In press] Mycoplasmal Conjunctivitis in House Finches: The Study of an Emerging Disease. In Wildlife Disease Ecology: Linking Theory to Data and Application. Cambridge University Press.
Germain, R. R., R. Schuster, C. E. Tarwater, W. M. Hochachka, and P. Arcese (2018). Adult survival and reproductive rate are linked to habitat preference in territorial, year-round resident Song Sparrows Melospiza melodia. Ibis 160:568–581.
Fleming-Davies, A. E., P. D. Williams, A. A. Dhondt, A. P. Dobson, W. M. Hochachka, A. E. Leon, D. H. Ley, E. E. Osnas, and D. M. Hawley (2018). Incomplete host immunity favors the evolution of virulence in an emergent pathogen. Science 359:1030–1033.
Yandell, D. D., W. M. Hochachka, S. Pruett-Jones, M. S. Webster, and E. I. Greig (2018). Geographic patterns of song variation in four species of Malurus fairy-wrens. Journal of Avian Biology 49:jav-01446.
Dokter, A. M., A. Farnsworth, D. Fink, V. Ruiz-Gutierrez, W. M. Hochachka, F. A. La Sorte, O. J. Robinson, K. V. Rosenberg, and S. Kelling (2018). Seasonal abundance and survival of North America's migratory avifauna determined by weather radar. Nature Ecology & Evolution 2:1603–1609.
Dhondt, A. A., K. V. Dhondt, A. P. Dobson, S. J. Geary, D. M. Hawley, W. M. Hochachka, D. H. Ley, E. R. Tulman, and K. Pflaum (2018). Epidemic spread and evolutionary changes in an emerging pathogen following a host shift from poultry to wild birds. Investigación en Ciencia Animal 2:149–161.
Johnston, A., D. Fink, W. M. Hochachka, and S. Kelling (2018). Estimates of observer expertise improve species distributions from citizen-science data. Methods in Ecology and Evolution 9:88–97.
Miller, E. T., D. N. Bonter, C. Eldermire, B. G. Freeman, E. I. Greig, L. J. Harmon, C. Lisle, and W. M. Hochachka (2017). Fighting over food unites the birds of North America in a continental dominance hierarchy. Behavioral Ecology 28:1454–1463.
La Sorte, F. A., D. Fink, P. J. Blancher, A. D. Rodewald, V. Ruiz-Gutierrez, K. V. Rosenberg, W. M. Hochachka, P. H. Verburg, and S. Kelling (2017). Global change and the distributional dynamics of migratory bird populations wintering in Central America. Global Change Biology 23:5284–5296.
Sullivan, B. L., T. Phillips, A. A. Dayer, C. L. Wood, A. Farnsworth, M. J. Iliff, I. J. Davies, A. Wiggins, D. Fink, W. M. Hochachka, A. D. Rodewald, et al. (2017). Using open access observational data for conservation action: A case study for birds. Biological Conservation 208:5–14.
Wood, E. M., S. Barker Swarthout, W. M. Hochachka, R. W. Rohrbaugh, K. V. Rosenberg, and A. D. Rodewald (2017). An improved survey method for monitoring population trends of Golden-winged Warblers and other patchily distributed birds. Journal of Field Ornithology 88:387–398.
Dhondt, A. A., K. V. Dhondt, W. M. Hochachka, D. H. Ley, and D. M. Hawley (2017). Response of House Finches recovered from Mycoplasma gallisepticum to reinfection with a heterologous strain. Avian Diseases 61:437–441.
Reynolds, M. D., B. L. Sullivan, E. Hallstein, S. Matsumoto, S. Kelling, M. Merrifield, D. Fink, A. Johnston, W. M. Hochachka, N. E. Bruns, M. E. Reiter, et al. (2017). Dynamic conservation for migratory species. Science Advances 3:e1700707.
Horton, K. G., B. M. Van Doren, P. M. Stepanian, W. M. Hochachka, A. Farnsworth, and J. F. Kelly (2016). Nocturnally migrating songbirds drift when they can and compensate when they must. Scientific Reports 6:21249.
La Sorte, F. A., D. Fink, W. M. Hochachka, and S. Kelling (2016). Convergence of broad-scale migration strategies in terrestrial birds. Proceedings of the Royal Society B: Biological Sciences 283:20152588.
Freeman, B. G., A. M. Class Freeman, and W. M. Hochachka (2016). Asymmetric interspecific aggression in New Guinean songbirds that replace one another along an elevational gradient. Ibis 158:726–737.
Winter, M., W. Fiedler, W. M. Hochachka, A. Koehncke, S. Meiri, and I. De la Riva (2016). Patterns and biases in climate change research on amphibians and reptiles: A systematic review. Royal Society Open Science 3:160158.
Wood, E. M., S. E. Barker Swarthout, W. M. Hochachka, J. L. Larkin, R. W. Rohrbaugh, K. V. Rosenberg, and A. D. Rodewald (2016). Intermediate habitat associations by hybrids may facilitate genetic introgression in a songbird. Journal of Avian Biology 47:508–520.
Zuckerberg, B., D. Fink, F. A. La Sorte, W. M. Hochachka, and S. Kelling (2016). Novel seasonal land cover associations for eastern North American forest birds identified through dynamic species distribution modelling. Diversity and Distributions 22:717–730.
Farnsworth, A., B. M. Van Doren, W. M. Hochachka, D. Sheldon, K. Winner, J. Irvine, J. Geevarghese, and S. Kelling (2016). A characterization of autumn nocturnal migration detected by weather surveillance radars in the northeastern USA. Ecological Applications 26:752–770.
La Sorte, F. A., W. M. Hochachka, A. Farnsworth, A. A. Dhondt, and D. Sheldon (2016). The implications of mid-latitude climate extremes for North American migratory bird populations. Ecosphere 7:e01261.
La Sorte, F. A., W. M. Hochachka, A. Farnsworth, D. Sheldon, B. M. V. Doren, D. Fink, and S. Kelling (2015). Seasonal changes in the altitudinal distribution of nocturnally migrating birds during autumn migration. Royal Society Open Science 2:150347.
Kelling, S., D. Fink, F. A. La Sorte, A. Johnston, N. E. Bruns, and W. M. Hochachka (2015). Taking a “Big Data” approach to data quality in a citizen science project. Ambio 44 Suppl 4:601–611.
Kelling, S., A. Johnston, W. M. Hochachka, M. Iliff, D. Fink, J. Gerbracht, C. Lagoze, F. A. La Sorte, T. Moore, A. Wiggins, W.-K. Wong, et al. (2015). Can observation skills of citizen scientists be estimated using species accumulation curves? PLOS ONE 10:e0139600.
La Sorte, F. A., D. Fink, W. M. Hochachka, J. L. Aycrigg, K. V. Rosenberg, A. D. Rodewald, N. E. Bruns, A. Farnsworth, B. L. Sullivan, C. Wood, and S. Kelling (2015). Documenting stewardship responsibilities across the annual cycle for birds on U.S. public lands. Ecological Applications 25:39–51.
Johnston, A., D. Fink, M. D. Reynolds, W. M. Hochachka, B. L. Sullivan, N. E. Bruns, E. Hallstein, M. S. Merrifield, S. Matsumoto, and S. Kelling (2015). Abundance models improve spatial and temporal prioritization of conservation resources. Ecological Applications 25:1749–1756.
Wesley Hochachka
Center Avian Population Studies
Projects eBird
Office(607) 254-2484
Email wmh6@cornell.edu

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Golden-cheeked Warbler by Bryan Calk/Macaulay Library