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4. Moving from the lab to the landscape: Extending the role of ecology in risk assessment (TU4/6) The ecology of birds in arable landscapes: impliations for risk assessment. Prosser, Phil1, Crocker, Joe1, Irving, Paul1, Bone, Phil1, Hart, Andy1, 1 Central Science Laboratory, York, North Yorkshire, UK ABSTRACT- In typical pesticide risk assessments, regulators attempt to protect worst case species in worst case scenarios. However, it is often unclear which species are most vulnerable and how vulnerable they are likely to be. Therefore we collected data on birds use of different arable crops. We used these findings to select species for more detailed study using radio-tracking. As a worst case, regulators often assume that all a bird's food intake is contaminated by pesticide. Our radio-tracking data suggest that for skylarks, linnets, yellowhammers and blackbirds, typical individuals spend less than 10% of their active time in cropped habitats; however worst case individuals (from the 5% tail of the distribution) spend 95% of their time there. Furthermore the range covered by many individuals covers more than the single field scenario typically used in risk assessments, raising the question of what scale is appropriate for regulatory risk assessment of pesticides. Key words: arable landscape, avian risk assessment, radio-tracking, scale |
