Origin determination of mallard duck via stable isotopes

Mallards (Anas platyrhynchos) originating from farms are still observed in the wild, despite a ban on the release of game birds in force since 1991. Enforcement of such illegal releases is not self-evident, as it depends entirely on catching the releaser in the act. Research on the isotopic composition of mallard duck feathers could contribute to more efficient enforcement, especially in detecting animals from farms and released into the wild. A similar method was previously used successfully in both partridge and pheasant.