This project will explore how environmental variables impact on the ability of different individuals in a population to resist and tolerate infection in a long term study of vulnerable seabirds in the North Sea.
Understanding how environmental conditions alter the dynamics of disease in wild animal populations is key to understanding population resilience at a time of global change. All wildlife populations experience a wide range of infections that can affect their both their own success and cross species boundaries to pose risks to human and animal health. Given climate change is predicted to lead to wider fluctuations in environmental conditions, understanding how environmental variation affects the ability to resist and tolerate infection is key to understanding it’s potential impact. We have shown that successful breeding in a long-lived, threatened seabird, the European shag Phalacrocorax aristotelis, is heavily constrained by parasitism, but that these effects vary from year to year and with average population breeding success. However, both the environmental drivers and the proximate mechanisms underlying these different host responses remain unclear. When conditions are sub-optimal resources may be directed away from two key groups of mechanism; resistance whereby mechanisms such as the immune response are required to limit parasite establishment or tolerance whereby individuals may pay a higher cost, for example on breeding success, to tolerate a given level of burden.
Possible research questions
What abiotic factors/climate variables might affect host resources available for mechanisms of resistance and tolerance?
Are environmental conditions in the current breeding season key or are carry over effects from historically poor conditions more important?
Do the effects operate directly on an individual or indirectly through other individuals in a population?
Is one sex more susceptible to environmental fluctuations than another?
This project will combine data analysis of both new and historical long-term data with field studies (based on the Isle of May National Nature Reserve). We have established a range of techniques that tell us about different aspects of parasitic infection being dealt with by the host. For example, this is one of the few model systems where parasite load can be directly observed, non-destructively, in situ using endoscopy allowing measurement of worm burdens in the same individuals over time when they may experience a range of environmental conditions. We can combine this with 30 years of life history data on known individuals which we can track throughout their lifetime, both during their breeding season on the Isle of May and over winter while dispersed throughout the North Sea. The populations is partially migratory with some individuals overwintering in substantially different environment conditions than residents. We are developing a range of both immunological measures of resistance and molecular techniques to measure levels of epigenetic gene regulation and how this varies under different environmental conditions. Parasites may also be removed with the use of anti-helmitics to allow experimental approaches to ask specific questions.
Year 1: Training in database management, statistical modeling techniques, immunological and parasitological techniques and analyses of environmental variation on measures of infection.
Year 2: Field experiments and field data collection on migration location variables and infection levels and immune analyses.
Year 3: Field data collection and analyses examining the impact of environmental variation on demographic responses to infection.
A comprehensive training programme will be provided comprising both specialist scientific training and generic transferable and professional skills including animal handling, field skills and molecular and parasitological lab based skills aswell as training in data management and analysis. The project is part of on an ongoing collaborative project between Dr Emma Cunningham at the University of Edinburgh ( http://cunningham.bio.ed.ac.uk/
), Dr Sarah Burthe (http://www.ceh.ac.uk/staff/sarah-burthe
) based at CEH Edinburgh and Francis Daunt (http://www.ceh.ac.uk/staff/francis-daunt
) based at CEH Edinburgh. See also http://www.ceh.ac.uk/sci_programmes/IsleofMayLong-TermStudy.html
). The project also provides the student the opportunity to interact with a number of bodies involved with fishery and seabird conservation in the North Sea and to direct the scope of the project within the broad remit stated above.
Students should have at least an upper 2.1 degree in a related biological subject and a first and/or MSc or equivalent research experience would be an advantage. All training will be provided but experience of field work and/or lab based skills in parasitology or immunology would be of further benefit.
(all papers of previous PhD students):
Hicks, O, Green, JA, Daunt, F, Cunningham, EJA, Newell, M, Butler, A & Burthe, SJ (2019) Sublethal effects of natural parasitism act through maternal, but not paternal; reproductive success in a wild population. Ecology. DOI: 10.1002/ecy.2772
Granroth-Wilding, HMV, Daunt, F, Cunningham EJA, Burthe S (2016) Individual variation in parasite burdens in a wild population. Parasitology 144; 248-258
Granroth-Wilding, HMV, Burthe S, Lewis S, Hepborn, K, Takahashi, EA, Newell, M, Daunt, F, Cunningham EJA (2015) Indirect effects of parasitism: costs of infection to other individuals can be greater than direct costs borne by the host. Proceedings of the Royal Society B, 282 (1811) Article Number:20150602
Granroth-Wilding, HMV, Burthe, S, Lewis, S, Reed, TE, Herborn, KA, Newell, M, Takahashi, E, Daunt, F, Cunningham, EJA (2014) Parasitism in early life: environmental conditions shape intra-brood variation in responses to infection. Ecology and Evolution 4, (DOI: 10.1002/ece3.1192)
Reed, TE, Daunt, F, Kiploks, AJ, Burthe, S, Granroth-Wilding, HMV, Takahashi, EA, Wanless, S, Cunningham, EJA (2012) Impact of parasites in early life: Contrasting effects on juvenile growth for different family members. PLOS One 7(2): e32236.
Reed, TE, Daunt, F, Hall, ME, Phillips RA, Wanless, S, Cunningham, EJA (2008) Parasite treatment affects maternal investment in sons. Science 321: 1681-1682.