PhD Project: Using isotopic forensics to recreate a lifetime profile of migratory movement and animal health
Effective conservation of a migratory species requires an in depth understanding of the animal’s ecology, including the annual route taken, how diet and nutritional status fluctuate along the way and the implications this has for health overall. However, finding a feasible technique that allows us to monitor the diet and health of wild animals and track their movements is challenging, as rarely will one method provide insights into such a range of ecological traits. Current studies are typically limited to either migratory patterns, diet, or the physiological changes affecting health, and traditional methods of recording each often come with their own significant limitations. Stable isotope analysis offers a solution to many of these common issues and can be applied to simultaneously study movement and the relationship of diet to health.
The stable isotope ratios found within an animal’s tissues will reflect those present in their local foodweb. As a result, interpretation of animal tissue values can provide information on the components of the animal’s diet and the provenance of these food sources, allowing them to effectively act as tracers of nutrient flow. This allows us to retrospectively reconstruct diets and movements that occurred in the past and at unknown locations, and to understand the effect they have on the health and fitness of animals — information unobtainable by other means. Keratinous tissues, such as hair and nails, are of particular interest for this type of analysis; they are continuously grown and metabolically inert after synthesis, and therefore have the potential to contain a timeline of data.
My project aims to use the analysis and interpretation of stable isotope ratios in tail hair samples to investigate several interlinked aspects of blue wildebeest (Connochaetes taurinus) ecology. This is in the form of four main sections:
- Using δ2H in Serengeti water and wildebeest hair to track migration
- δ13C & δ15N as proxies for diet and nutritional status in wildebeest
- Method development for compound specific δ2H analysis in essential vs. non-essential amino acids and how this relates to wildebeest nutrition
- Analysing additional elements (δ34S) to increase the spatial resolution of wildebeest movement data gained from δ2H analysis
Black, S., Eley, Y., Loveridge, A., Wood, K. R., Trethowan, P. & Macdonald, D. (2016) “Pussy cat, pussy cat where have you been..?” Evaluating the use of stable isotopes, radiogenic isotopes and trace elements for investigating the ecology of Panthera leo. Ecology and Evolution, ISSN 2045-7758 (In Press).
Wood, K. R., Newton, J., McGill, R. A. R., Hopcraft, J. G. C., Preston, T. & Evans, N. P. (2016) Using δ2H to track the Serengeti migration. Poster presented at 10th International Conference on the Applications of Stable Isotope Techniques to Ecological Studies, Tokyo, Japan.