QUADRAT DTP: Trophic interactions and the ecology of emerging lungworm infections under global warming

Recent decades have seen big changes in the distribution and epidemiology of lungworms and their importance as pathogens in wildlife systems: notably, Angiostrongylus vasorum in foxes in Europe, Angiostrongylus cantonensis in rats and people in the sub-tropics, Crenosoma striatum in hedgehogs, and various species in ungulates in the thawing north. These systems all involve gastropod mollusc intermediate hosts, and often additional animal species as paratenic (transport) hosts, so transmission occurs through trophic networks. Connections within these networks are likely to be affected by climate change, yet they have been neglected relative to direct effects of climate on parasite development.

This project will explore the importance of host behaviour to the transmission of gastropod-borne nematodes under climate change, for selected systems and in relation to trophic interactions. Research questions could include:

-         For gastropod intermediate hosts: does climate affect food preferences and ingestion of infected definitive host faeces, or onward availability for consumption by definitive or paratenic hosts? Can behavioural thermoregulation limit or extend the microclimatic envelope and modify parasite development rates?

-         For paratenic / transport hosts: how is parasite flow through a food web affected by environmental influences on species composition and energy flux? Could climate change modulate interspecific competition and affect the ratio of suitable and refractory hosts in a food web?

-         For definitive hosts: does feeding behaviour change with extreme weather and other environmental disturbance? Can parasite effects on fitness alter defecation sites and microclimates in which parasites will develop?

To address these questions, parallel approaches will be taken, involving experimental, field and modelling work. Captive gastropods will be exposed to controlled conditions and their behaviour evaluated in relation to transmission-relevant outcomes such as diet and microclimate selection. Parasite detection methods will be developed for rapid and affordable detection across food chains: this will include harvesting of reference and comparator material by dissecting wild hosts (e.g. from wildlife rehabilitation centres and, for tropical species, wet markets). Laboratory work will apply molecular methods including portable PCR and sequencing systems. Modelling will be used to compare parasite distribution, abundance and seasonality with and without taking into account these modifying factors, and to project likely responses under climate change scenarios.

Because several different parasite-host systems and methodological approaches are possible, the direction of the project can be adapted to the interests, abilities and training needs of the successful candidate. In the first year, they will: (i) produce global parasite distribution maps for the best-known species and identify where macroclimate alone cannot explain present range; (ii) conduct at least one experiment on the gastropod colony to determine climate responsiveness of a transmission-relevant behaviour; and (iii) collect reference parasite material and trial molecular versus traditional methods for detection of a selected metastrongylid species in transport hosts. Thereafter, the student will have freedom to develop the project according to their interests and taking advantage of the research group’s excellent facilities and global connections. 

Candidate Background: The successful candidate should have a background in biological sciences and an interest in parasites and epidemiology. Laboratory and quantitative skills are desirable.

More project details are available here: https://www.quadrat.ac.uk/quadrat-projects/

How to apply: https://www.quadrat.ac.uk/how-to-apply/