**4. Conclusion**

A large non-invasive program allowed an important sampling of European otter and osprey tissues for various pesticides contamination study. Results showed that otter and osprey could be used as good sentinels of organochlorine and, to a lesser extent, organophosphate pesticides and some herbicides accumulation in aquatic food chains. Carbamates and pyrethroids pesticides were not detected in those top-predators fisheating species. Organochlorine, organophosphate pesticides and herbicides concentrations remained low and under values of concern for species direct short-term conservation. Regular increase in populations observed since three decades in France seemed to confirm a low impact of global contamination on otter and osprey. Nevertheless, long-term consequences of global contamination on otter and osprey behaviour (*e.g.* prey or habitat foraging, hunting, mating or territory defence), synergies or antagonisms between compounds or potential long-term endocrine disruptors effects of low-concentrated contaminants remains unknown and should be elucidated during future standard monitoring of these sentinels species.

#### **5. Acknowledgments**

Authors wish to thank the following structures or people for otter and/or osprey conservation and study or samples providing (see text): Muséum d'Orléans (sampling coordination), MEEDDM, DREAL Centre, LPO, UFCS, CRBPO, ONCFS, ONEMA, ONF, RTE, EDF, R. Wahl, private land owners and companies, Ph. Guillet & M.-F. Larigauderie of the City of Orléans Museum, D. Vey & the technical team of VetAgro Sup Toxicology unit, "Loiret Nature Environnement" and other environmental associations.

This study was financially supported by: European Commission (FEDER), « Plan Loire Grandeur Nature 2007-2013 », Etablissement Public Loire, Agence de l'Eau Loire-Bretagne, French Ministry of Environment (MEEDDM, DREAL Centre, Plan National d'Actions pour le balbuzard pêcheur en France), VetAgro Sup, Ville d'Orléans, Office National des Forêts, Parc naturel régional des Volcans d'Auvergne, Parc interrégional du Marais poitevin, and CNRS.
