Exposure uncertainty

Przewalski's horses

Przewalski's horses

Elk

Elk

Wild boar

Wild boar

Assessing the uncertainty of exposure of wildlife under field conditions

The current approaches used to estimate the exposure of wildlife to ionising radiation have been criticised as being too simplistic because they do not consider how animals utilise their environment. The ‘state-of-the-art’ is typically to average the available measurements of media concentrations or, at best, to use geographical information systems to estimate an average concentration within a typical home range for a given species. There is little evidence to support or counter the criticisms or to evaluate uncertainties associated with existing methodologies. Whilst there have been a number of international model-data comparisons, few studies have attempted to measure the exposure of wildlife to validate predictive exposure models. 

Hypotheses:

Current simplistic assumptions which ignore how animals utilise their environment ensure wildlife is protected by generating a conservative estimate of exposure

Wildlife camera traps

Working with our Ukrainian collaborators (Chornobyl Center), we have deployed 42 wildlife trap cameras within the Chernobyl exclusion zone (CEZ) (see initial camera sites being established). We will also be able to use the cameras to make population estimates thereby providing a useful input to the debate on the impact of ionising radiation on wildlife in the CEZ.

CLICK HERE to view a selection of photographs from the trap cameras.

Estimating the exposure of wild mammals

We are evaluating pathways of exposure for large mammals We are studying mammals due to their relatively large home ranges which enables us to assess the often  simplistic assumptions that are currently used in exposure assessments. We have fitted reindeer in an area of Norway with a variety of different passive dosimeters. The reindeer also had GPS collars. The resultant data will enable us to determine the actual external dose rate received and compare this to the dose predicted using: (i) ‘the traditional approaches’ of assuming home ranges around the point of capture; (ii) spatial behaviour models and GPS tracking data. Watch reindeer being collected, fitted with dosimeter boxes and live-monitored here

Faecal DNA

We will quantify internal exposure of these animals using a combination of faecal DNA analysis and live-monitoring.  A recently developed DNA metabarcoding approach allows determination of dietary composition through faecal analysis.  This state of the art methodology is being used to evaluate uncertainties in the estimation of internal exposure resulting from diet selection. We are supplementing the faecal DNA-informed evaluation of internal exposure with live-monitoring of the animals at the start and end of the exposure assessment.The University of Comte (France), who have contributed to the development of faecal DNA bar coding to estimate dietary composition, will be collaborating in this aspect of our work.

Bank vole fitted with TLD

Cs deposition in the CEZ (Chornobyl Center)

Inspecting wolf faeces in the CEZ

We will provide an evaluation of the extent to which current simplistic and pragmatic exposure assumptions ensure that wildlife are protected.

Watch reindeer being collected, fitted with dosimeter boxes and live-monitored

Outputs from this work (click on title to access paper):

For further information contact: Prof. Mike Wood (University of Salford)