Duck's not dead: Does restocking with captive bred individuals affect the genetic integrity of wild mallard (Anas platyrhynchos) population?

► We evaluate the effects of introduced captive-reared mallards on wild population. ► We genotyped 14 microsatellites, the MHC I locus and the control region. ► All genetic markers show differentiation between wild and captive mallards. ► Hybridization between captive and wild mallards is relatively common. ► Release of captive-reared mallards affects the genetic integrity of wild populations.