Cardiff School of Biosciences: Tortoises as analogue species providing the ecosystem service of habitat restoration through grazing (PhD Studentship)
Reference Number: R1043
Key Studentship Information
Project title: Tortoises as analogue species providing the ecosystem service of habitat restoration through grazing
Many habitats worldwide have suffered disruption to ecosystem function following the loss of keystone species, leading to detrimental changes to habitats that result in further species losses. Where reintroduction is impossible, because the species is extinct globally, there is growing interest in the use of analogue species to restore critical functions.
Here, in Cardiff School of Biosciences, we will study the introduction of alien Aldabran tortoises on Ile aux Aigrettes, Mauritius, to replace extinct species of giant tortoise and perform the ecosystem service of habitat restoration. Giant tortoises were the dominant grazers on many tropical islands before hunting wiped them out, eliminating the beneficial effects of grazing, such as promoting greater biodiversity and creating habitats for other plant and animal species.
Plant species on the island will first be barcoded. Tortoise grazing preference will be studied by analysing their faecal samples using Next Generation Sequencing (NGS) which, after calibration, will provide an approximate measure of the biomass of different plants consumed. Plants consumed will be identified from our barcode library. Monte Carlo simulations will be used to analyse prey choice, testing for deviations from random grazing. Food webs will be constructed measuring the strength of trophic interactions with different plants over time and between sexes. Spatial statistics will be used to measure aggregation by the tortoises to particular plant species. In addition, the potential impacts of the action of tortoises as ecosystem engineers will be assessed by examining the diets of two re-introduced but native species, Pink Pigeons and Telfair’s Skinks. Plant material in the diets of the pigeons and skinks will be analysed by NGS and food webs constructed, as for the tortoises. Analyses of the food web will be undertaken to demonstrate how tortoise grazing may promote plant species critical to other rare species (especially pigeons and skinks). The effects of tortoise grazing will be retrospectively assessed, taking advantage of data from existing long-term studies of plant communities on the island.
Use of NGS in this way, to monitor the effects of analogue species providing the ecosystem service of habitat restoration is, as far as we are aware, unprecedented and will provide a blueprint for future detailed work in this field. This is a collaborative project involving Cardiff University, Durrell Wildlife Conservation Trust and the Mauritian Wildlife Foundation.
Supervisors: The project will be based at Cardiff University. The primary supervisor will be Professor William O.C. Symondson, co-supervised by Professor Michael W. Bruford. External supervision and supervision in the field will be provided by Dr Nik Cole of Durrell Wildlife Conservation Trust, in association with Dr Nicolas Zuel of the Mauritian Wildlife Foundation.
The ideal candidate should have some molecular biology experience and a willingness to work for long periods in the field on tropical islands. Candidates should have a high 2:1 or 1st class degree, or a Masters, in a relevant subject. The studentship is available to UK citizens, and European Union citizens who have been in the UK for the three years prior to the start of the studentship.
The project is funded by a Natural Environment Research Council CASE studentship with additional funding from Durrell Wildlife Conservation Trust. The student will receive a stipend starting at £13,725 per annum for 3.5 years in addition to the tuition fees being paid. Full support is only available to UK citizens plus European Union citizens who have been in the UK for the three years prior to the start of the studentship.
How to Apply
Application Deadline: April 19th 2013
For more information on the project, please contact Professor Symondson (firstname.lastname@example.org). Further information on the application process can be obtained by contacting the Cardiff School of Biosciences Postgraduate Secretary, Mrs Swapna Khandavalli (email@example.com)