As in all members of the "mallardine" clade of ducks, they are able to produce fertile hybrids with their close relatives, the American black duck and the mallard. This has always been so to a limited extent; individuals of the migratory American black ducks which winter in the mottled duck's range may occasionally stay there and mate with the resident species, and for the mallard, which colonized North America later, the same holds true. Genetic tools have been developed in order to robustly classify hybrids and to assess and monitor the genetic dynamics of introgression between the Florida mottled duck and the mallard.