Mrs J. (Jenni) Welsh

Room:

T544

Phone:

+31-(0)222-319674

Email:

Curriculum vitae:

1985 born in Suffolk, England
2007 MSc Aquaculture and the Environment; Univ. of Wales
2010 Master of Research, Galway-Mayo Institute of Technology.
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Specialization:

Marine ecology

Project:

Biodiversity and disease risk in marine systems

Courses:

DEB tele course

Publications:

This project explores a novel aspect of the role of biodiversity in marine ecosystem functioning by linking the study of diseases with community ecology. Ambient organisms can interfere with pathogen transmission (e.g. by consuming infective stages) and thus reduce infection levels and disease outbreaks in hosts (`dilution effect'). Whilst this phenomenon has previously been reported in marine systems (Thieltges et al. 2008, 2009, Johnson and Thieltges 2010) little is known about the mechanisms that result in a reduction of infectious stages. This research attempts to identify and unravel these mechanisms using two well established and representative pathogen-host model systems, trematodes in benthic invertebrates and viruses in phytoplankton. Laboratory experiments will investigate the extent to which ambient organisms interfere with pathogen transmission and if specific diversity effects (instead of simple density effects) on disease risk exist. In addition, field trials will be conducted to ascertain whether the results from the laboratory experiments are true to the natural environment. Finally, the obtained results will be integrated into existing population models and food webs to investigate how dilution effects alter disease dynamics in their hosts.

Aims

1.To explore dilution effects within marine ecosystems and understand the underlying biotic mechanism that result in a reduction of infective stages.
2. To apply the findings of 1 to existing marine models in order to assess their impacts on a community level.

Experiments

Field and laboratory based mesocosm experiments shall be conducted to assess the effects of dilutor size, density and diversity as well as pathogen dose, on parasite transmission. Laboratory experiments shall be undertaken in climate controlled chambers at the Royal Netherlands Institute for Sea Research. Field experiments will be conducted in the Dutch Wadden Sea.

Bibliogrpahy

Johnson, P. T. J., and D. W. Thieltges. 2010. Diversity, decoys and the dilution effect: how ecological communities affect disease risk. The Journal of experimental biology 213:961-70. doi: 10.1242/jeb.037721.
Thieltges, D. W., M. D. Bordalo, a C. Hernández, K. Prinz, and K. T. Jensen. 2008. Ambient fauna impairs parasite transmission in a marine parasite-host system. Parasitology 135:1111-6. doi: 10.1017/S0031182008004526.
Thieltges, D. W., K. Reise, K. Prinz, and K. T. Jensen. 2009. Invaders interfere with native parasite-host interactions. Biological Invasions 11:1421-1429. doi: 10.1007/s10530-008-9350-y.

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