PhD position: Modelling Effects of Chemicals on Polar Bear Population Dynamics

CREAM is offering a total of 20 Ph.D. positions and 3 postdoctoral positions, which will be formally advertised in September 2009 with expected start dates in late 2009 or early 2010. CREAM is an EC funded Initial Training Network of 13 partner organisations and 9 associated partner organisations from 9 European countries. The partners in CREAM represent the main sectors involved in chemical risk assessment (industry, academia, regulatory authorities) and who are interested in exploring how mechanistic effect models can add value to the risk assessment process. The overall aim of CREAM is to develop and experimentally validate a suite of mechanistic effect models that are based on Good Modelling Practice. CREAM will provide world class training for the next generation of ecological modellers, emphasizing transparency and rigorous model evaluation as core elements of the modelling process.

We are looking for candidates with experience in one or more of the following areas: population ecology; ecotoxicology; ecological risk assessment; ecological modelling; programming.

Salary and terms of employment will be in accordance with Marie Curie rules of the European Commission (http://ec.europa.eu/research/mariecurieactions/careers_en.htm ). According to these rules, applicants must be nationals of a member state, associated country or third country. They must be nationals of a country other than that of the premises of the host organisation where they will carry out their project. Researchers must not have resided or carried out their main activity (work, studies, etc) in the country of their host organisation for more than 12 months in the 3 years immediately prior to the date of selection by the host institution (short stays such as holidays are not taken into account).

Applicants should send CV, list of publications, reprints of relevant publications, copies of academic transcripts, two letters of reference including contact information of the referees, and a one-page statement of applicant’s expected contribution to and benefit from participation in CREAM. Applicants should clearly indicate (preferably indicating priority of preference) for which CREAM project(s) they would like to be considered. Applications should be sent by email to volker.grimm@ufz.de.

Details on the projects are described on the corresponding webpages of this site. Details on the job announcements are linked to pages desribing the project partners (see also the overview table below).

Potentially interested applicants are encouraged to contact the relevant partners (AVAILABLE ONLINE) prior to formally submitting an application. Positions are subject to funding.

Expected Application Deadline: 15 October 2009

PhD position: Modelling effects of chemicals on polar bear population dynamics

Many toxic chemicals that are used in agriculture and industry are long-range transported and can accumulate in the food chain and affect top predators far from the area where they are applied. The polar bears in Greenland, Svalbard and Canada are, for example, exposed to high concentrations of PCB, brominated flame retard

Polar bears

ants (PBDEs) and Perfluoroalkyl compounds (PFAS) even though the substances have never been used in theArctic .

The concentrations in polar bears may be high enough to affect the fecundity, behaviour, immune system, internal organs and in some cases the survival of individual bears. Data is currently available on the spatial distribution of the polar bears from satellite tagging as well as their prey, on variations in climatic conditions, on anthropogenic contaminant concentrations in the bears as well as on the toxicity of these chemicals. Data are also congregating on differences in feeding strategies of the polar bears based on Stable Isotope analysis and fatty acids. It is not known, however, how spatial and temporal variations in these factors affect the over-all dynamics of the populations.

The aim of this project is to develop individual-based and matrix models for studying the population-level effects of food availability and chemical concentrations on polar bear population dynamics in three geographically separated bear populations. The models will be validated by comparing the simulated patterns to bear distribution patterns and to patterns on individual behaviour as observed using remote sensing. A major focus of the project will be to evaluate what level of model complexity that is needed in order to generate sufficiently accurate population level patterns. This will be studied by building a hierarchy of models of gradually increasing complexity, starting with a simple non-spatial model. All models will be developed following Good Modelling Practice and will be documented using the ODD protocol. The project will significantly contribute to our understanding of the relative importance of the mechanisms that control the dynamics of the vulnerable polar bear populations.

Supervisor: Jacob Nabe-Nielsen, NERI, Aarhus University, DK (nabe@dmu.dk). Co-supervisor: Volker Grimm,UFZ. Advisor: Rune Dietz, NERI, Aarhus University, DK