 In order to address some of these concerns some GMOs have been developed with traits to help control their spread.To prevent the genetically modified salmon inadvertently breeding with wild salmon, all the fish raised for food are females, triploid, 99% are reproductively sterile, and raised in areas where escaped salmon could not survive.Bacteria have also been modified to depend on nutrients that cannot be found in nature, and genetic use restriction technology has been developed, though not yet marketed, that causes the second generation of GM plants to be sterile.