Princeton Zebra Project

Institution: 
Princeton University (United States)

Principal Investigator: 
Daniel Rubenstein, dir@princeton.edu

Project Manager: 
Rosemary Warungu, rosemary.warungu@mpala.org

In the savannas of Northern Kenya, plains zebras (Equus burchelli), the most numerous of the wild ungulates, coexist with their close evolutionary relative, the Grevy's zebra (Equus grevyi), one of the world’s most endangered mammals. We ask: Why is one species common and the other rare, despite being similar in physiology, morphology, and ecology? This is a puzzle rarely tackled, yet as environments change due to local and global factors, it becomes increasingly important to understand the drivers of population change. By addressing the causes of differential abundance in similar, sympatric species, we can gain general insights into the mechanisms of population decline and regulation.  In addition, by following the fates of individuals, several ancillary consequences with respect to demography, genetics and individual health will emerge.  All will help shape conservation strategies.

We now use AI and advanced visual recognition systems of images to follow individuals as they move, forage, and socialize at large spatial and temporal scales on landscapes that that can also now be characterized ecologically from satellite or drone imagery. These datasets and advanced statistical modeling will enable us to identify the behavioral rules that shape how individual movement decisions translate into population-level patterns.

Publications:

Kline, J., Afridi, S., Rolland, E.G., Maalouf, G., Laporte‐Devylder, L., Stewart, C., Crofoot, M., Stewart, C.V., Rubenstein, D.I. and Berger‐Wolf, T., 2025. Studying collective animal behaviour with drones and computer vision. Methods in Ecology and Evolution.

Conservation of the endangered Grevy's zebra: The influence of land use patterns on distribution and abundance in Samburu-Laikipia landscape, Kenya, DI Rubenstein, K Joseph Nderitu - Frontiers in Conservation Science, 2025

Hex, S.B. and Rubenstein, D.I., 2025. " Age of risk" shapes simpler multimodal communication in the juvenile plains zebra (Equus quagga). Communications Biology, 8(1).

Hex, S.B.S.W., Isbilen, E.S. and Rubenstein, D.I., 2025. Plains Zebras Prioritize Foraging Without Sacrificing Social Bonds During a Severe Drought. Ecology and Evolution, 15(1), pp.e70632-e70632.

Tombak, K.J., Nonnamaker, L.E., Parham, J.R., Stewart, C.V., Warungu, R. and Rubenstein, D.I., 2025. Darwin's hostile forces shape social scaling in equids: a comparison of group size dynamics in Grevy's and plains zebras. Animal Behaviour, 224, p.123158.

Abraham, J.O., Lin, B., Miller, A.E., Henry, L.P., Demmel, M.Y., Warungu, R., Mwangi, M., Lobura, P.M., Pallares, L.F., Ayroles, J.F. and Pringle, R.M., 2024. Determinants of microbiome composition: Insights from free-ranging hybrid zebras (Equus quagga× grevyi). Molecular Ecology, pp.e17370-e17370.

Hex, S.B. and Rubenstein, D.I., 2024. Using networks to visualize, analyse and interpret multimodal communication. Animal Behaviour, 207, pp.295-317.

Kirathe, J.N., Githaiga, J.M., Chira, R.M. and Rubenstein, D.I., 2024. Habitat selection by Grevy's zebra (Equus grevyi): Conservation implications. African Journal of Ecology, 62(1).

Tombak, K.J., Gersick, A.S., Reisinger, L.V., Larison, B. and Rubenstein, D.I., 2022. Zebras of all stripes repel biting flies at close range. Scientific Reports, 12, p.18617.

Smith, C.V., Gilbert, T.C., Woodfine, T., Kraaijeveld, A., Chege, G., Kimiti, D., Low-Mackey, B., Mutinda, M., Ngene, S., Rubenstein, D. and Wandera, A., 2022. Population and habitat connectivity of Grevy's zebra Equus grevyi, a threatened large herbivore in degraded rangelands. Biological Conservation, 274, p.109711.

Tombak, K.J., Easterling, L.A., Martinez, L., Seng, M.S., Wait, L.F. and Rubenstein, D.I., 2022. Divergent water requirements partition exposure risk to parasites in wild equids. Ecology & Evolution (20457758), 12(3).

Scheetz, A.A., Fenichel, E.P. and Rubenstein, D.I., 2022. Effects of a grazing permit market on pastoralist behavior and overgrazing in Kenya. Environmental Research Letters, 17(3), p.035002.

Chen, A., Reperant, L., Fischhoff, I.R. and Rubenstein, D.I., 2021. Increased vigilance of plains zebras (Equus quagga) in response to more bush coverage in a Kenyan savanna. Climate Change Ecology, 1, p.100001.

Esmaeili, S., Jesmer, B.R., Albeke, S.E., Aikens, E.O., Schoenecker, K.A., King, S.R., Abrahms, B., Buuveibaatar, B., Beck, J.L., Boone, R.B. and Cagnacci, F., .... Rubenstein, D.I. 2021. Body size and digestive system shape resource selection by ungulates: a cross-taxa test of the forage maturation hypothesis.