We released thousands of pheasants back in the late 70's and early 80's in west central MN and we found that releasing fewer adult birds in the spring resulted in more successful establishment of a population. Example: instead of releasing 300 6-10 week old birds that have to survive all summer, fall, and winter before they are even able to breed and lay eggs, we would keep them over winter and release 5 adult roosters with 25 adult hens in a location. The results were, at least this is what I think happened, is the hens breed right away and lay a clutch of eggs. Then the brood is 100% wild. They usual understanding is that 1 percent or so of the young birds released, make it through the winter so from 300 birds that would be 9 birds left in the spring. Conversely, If only 2 hens of the 25 released, successfully hatch a clutch of eggs from an adult release, the hope is that you would have MORE than 9 eggs between the two clutches hatch and get more "Wild" birds in the end. Of course having more hens successfully hatch a brood is prefered, but that's kind of how we justified the process. The trade off is the feed/housing costs/time to get the birds into spring. When we did this, we had establishment rates of more than 75% at the release locations for having birds survive through the winter and into the following spring. Either way, I wish you the best in getting those maddeningly elusive and wonderfully annoying birds established. Kudos Bud!!!