Poaching remains a key threat for rhinos in Africa, and as conservationists battle to end rhino losses, maximising population growth remains essential in order to provide long-term resilience to the wild populations.
The goal of the Kenya Black Rhino Action Plan (2017-2021) is to achieve a net growth of at least 5% per annum, maintained in at least six established breeding populations. The idea behind this is to use individuals from these populations to expand into new secure areas with suitable habitats while also maintaining genetic diversity.
In the case of Eastern black rhinos living outside of their natural range, they form a large proportion and potential genetically valuable subset of the total population, making them a crucial piece of the puzzle. These animals could, therefore, represent some valuable genetic diversity that has been lost in the wild. As of 2018, the European population of Eastern black rhino stood at 92 individuals with a steady growth rate of 4% in the five years prior.
Our current research project embraces this method and is designed to shed light on how to maximise reproductive performance both within and outside the natural range of the eastern black rhino, contributing to the global conservation effort. We believe that maximising the genetic diversity of both these populations is essential in order to provide resilience for this species in the long-term.
Working in partnership with the University of Manchester, we have been exploring ways to optimise the ex situ breeding programme by using what we call a conservation physiology toolbox, which looks at the physiological drivers of reproductive success. The results have allowed us to understand factors related to successful reproduction, target management efforts and support a zoo ‘baby boom’ of Eastern black rhinos. Building from this success, we are now focusing on incorporating genomic information into our ex situ breeding efforts to help maximise genetic diversity.
For black rhinos within their natural range, population performances can vary across various reserves. Working in collaboration with Kenyan Wildlife Service, Manchester Metropolitan and the University of Manchester, we aim to gain a better understanding of the drivers of population performances. To do this, we are using the non-invasive biomarker monitoring approach we developed within the zoo to identify potential constraints on reproduction in the wild Kenyan populations. We are also looking to understand the influence of ecological and genetic factors underlying variance in breeding performance.
The Big Life project at Chyulu works closely with local Maasai communities who are active participants in many conservation projects in the region. Since 2012, Chester Zoo has also provided major funding and educational support towards the highly innovative and hugely successful Maasai Olympics, a conservation-themed athletics event based on traditional warrior skills.
Edwards, K.L., Walker, S.L., Dunham, A.D., Pilgrim, M., Okita-Ouma, B., Shultz, S. 2015. Low birth rates and reproductive skew limit the viability of Europe’s captive eastern black rhinoceros Diceros bicornis michaeli Biodiversity and Conservation, 24(11),1-22. https://doi.org/10.1007/s10531-015-0976-7
Edwards, K.L., Shultz, S., Pilgrim, M. and Walker, S.L. 2015. Male reproductive success is correlated with testosterone in the eastern black rhinoceros (Diceros bicornis michaeli). General and Comparative Endocrinology, 213, 40-49. https://doi.org/10.1016/j.ygcen.2014.12.015
Edwards, K.L., Shultz, S., Pilgrim, M., Walker, S.L. 2015. Irregular ovarian activity, body condition and behavioural differences are associated with reproductive success in female eastern black rhinoceros (Diceros bicornis michaeli). General and Comparative Endocrinology, 214, 186-194. https://doi.org/10.1016/j.ygcen.2014.07.026
Edwards, K.L., McArthur, H.M., Liddicoat, T., Walker, S.L. 2014. A practical field extraction method for non-invasive monitoring of hormonal activity in black rhinoceros, Diceros bicornis. Conservation Physiology, 2(1). https://doi.org/10.1093/conphys/cot037
Watson, R., Munro, C., Edwards, K., Norton, V., Brown, J.L., Walker, S.L. 2012. Development of a versatile enzyme immunoassay for non-invasive assessment of glucocorticoid metabolites in a diversity of taxonomic species. General and Comparative Endocrinology, 186,16-24. https://doi.org/10.1016/j.ygcen.2013.02.001
Partners and collaborators
Photos of eastern black rhino in the wild were taken by Conservation Scholar, Nick Harvey.
Dr. Sue Walker
Dr. Mark Pilgrim