Can red seeds become green? Refining exposure assessment to minimize risks of pesticide-treated seeds to farmland birds

Resumen del trabajo presentado al Society of Environmental Toxicology and Chemistry (SETAC) Europe 27th Annual Meeting, celebrado en Bruselas (Bélgica) del 7 al 11 de mayo de 2017.Seed coating with pesticides is a widespread practice that reduced the necessyt yof spraying and the amount of active substances released to the environment. However, this practice poses a risk to granivorous birds, which could become intoxicated because of the ingestion of seeds that are not properly buried during sowing. After experimentally studying the toxicity of coated seeds to red-legged partridges, we initiate this project in order to chracterise the exposure of farmland birds to coated seeds, and to validate measures focused on mitigating risks through the reduction of the exposure. We will start validating non-invasive biomarkers to estimate pesticide exposure in order to use them as a monitoring tool in the field. Exposure assessment will be conducted, on the one hand, through GPS-tracking of partridges to study their spatial ecology and to determine how the occurrence of coated seeds in the field influences habitat use by these birds. On the other hand, we will analyse partridges’ diet by metabarcoding of excreta in order to relate diet composition with pesticide levels in faeces. Once exposure scenarios are determined, we will evaluate the efficacy of different measures, like burial of coated seeds or supplement of cleaned food, to reduce the risk of poisoning of partridges and other farmland birds. In order to make these measures applicable to the entire EU, we count on the collaboration of international teams that will evaluate the risk mitigation measures in other countries. This project aims at resolving a problem that affects different sectos of the society, which has motivated the involvement of farmers, hunters, pesticide manufacturers, governmental agencies, nature conservationist groups and environmnetal management business.Financed by the Spanish Ministry of Economy and Competitiveness.Peer Reviewe