SEGH Articles

Zoo Elephants Aid Wild counterparts in the Kruger National Park

04 November 2016
Eight zoo elephants from Knowsley Safari Park and Twycross Zoo have been contributing to work that is being carried out to reduce Human-Elephant Conflict surrounding the Kruger National Park.

Eight zoo elephants from Knowsley Safari Park and Twycross Zoo have been contributing to work that is being carried out to reduce Human-Elephant Conflict surrounding the Kruger National Park. This unique, interdisciplinary project involves environmental geochemistry, plant science, and animal health between a range of partners including BGS and the University of Nottingham (UoN) through the joint Centre for Environmental Geochemistry (

The working hypothesis is that the elephants in this study group originally from the Kruger National Park are deficient in phosphorus, owing to a deficiency in the (soil and) forage. This drives the elephants to supplement their phosphorus from the water, soil and forage on land surrounding a phosphate mine in close proximity to the National Park. En-route to the phosphorus mine, elephant incursion into nearby human settlements has resulted in human-elephant conflict, causing risk of injury and lost income. The results of the project may help to inform  key locations in the elephants’ home range where mineral-supplemented forage or mineral licks may be placed to reduce the drive to seek additional sources of phosphorus, thereby reducing human-elephant conflict. Samples (hair, toenail, blood and urine) from the UK elephants will be used to validate their possible use as biomarkers of mineral status in the wild: This is a brilliant example of the contribution captive animals can make to directly benefit research on their wild counterparts.



Five UK zoos have kindly agreed to assist with and contribute samples to this research with each zoo being visited four times throughout the year to collect necessary samples from the elephants and from items which the elephants consume from their environments in the zoos. Biological samples required include toenails, faecal samples, serum and tail hair. Environmental samples include all food items (browse, hay, grass, pellets and fruit and vegetables) consumed and soil and water samples to assess the influence of geochemistry on dietary intake and land use decisions. These will be analysed for “essential mineral” content (e.g. zinc, iron) to estimate dietary intake and possible seasonal changes in browse, grass and hay over the year. These data will be related to mineral measurements in the elephants’ biological samples to validate methodologies for use and comparison to wild elephants. 

In June, the second set of UK sample collection took place at Knowsley Safari Park, having commenced a first seasonal cycle in April at that facility. It was especially exciting to collect a longitudinal toenail sample from one individual that will be analysed by spatial analysis using techniques such as laser ablation coupled to ICP-MS or ion beam analysis to give an indication of mineral status over time in that elephant. We would like to thank all the elephant team at Knowsley Safari Park for their assistance with procuring samples and enthusiasm for the research and of course the elephants for their ongoing cooperation. We then moved on to Twycross Zoo for the first very successful sample collection at this facility. We would like to thank all of the elephant team at Twycross Zoo, especially Team Leader Andy Durham, and the veterinary team for their assistance.


Thanks to the NERC Envision Doctoral Training Programme, the Hermes Trust and Royal Society International Exchange scheme. The project is based on a Centre for Environmental Geochemistry collaboration between the Inorganic Geochemistry (Dr Michael Watts) and Stable Isotopes teams (Professor Melanie Leng) at BGS and Schools of Veterinary (Dr Lisa Yon) and Biosciences (Professor Martin Broadley & Professor Simon Langley-Evans) at the University of Nottingham. The collaboration is further strengthened by partners in five UK zoos and with partners in South Africa who have been studying elephant populations there for the past two decades, tracking elephant movements using GPS and GMS to better understand their habitat use.  In addition, Dr Ellen Dierenfeld (E.S.Dierenfeld Nutrition Consulting, LLC) is an internationally renowned expert on elephant nutrition and a co-investigator on this project.

I am very excited having started my PhD full time in October, having contributed to activities over the summer months in advance. I left my previous employment at the Zoological Society of London (ZSL), where I was Nutrition and Research Officer at London and Whipsnade Zoos for the past 4 years. My role included maintaining accurate diet records for all the animals within the collection, reviewing animal diets based on clinical need, working with procurement to source the myriad of food items needed to feed a zoo and working with keepers to implement diet changes. I continue to be a Research Advisor for the BIAZA Elephant Focus Group and aid the EAZA Elephant TAG Chair with the strategic planning of the TAG giving input into the direction of the group. This experience has put me in touch with the global captive elephant community and given me an understanding as to the work zoos can do to benefit wild counterparts. I look forward to starting this new challenge, collaborating with several UK zoos to directly advance field research and to employ a multi-disciplinary approach to the PhD research question – “Are land-use decisions made by elephants influenced by geochemistry?”

by Fiona Sach, PhD Student, NERC Envision DTP, BGS & University of Nottingham

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