If it does turn out that you have 8 drakes and only two hens, it will be a problem. You would need to get around 20 more hens or rehome some drakes. With 8 drakes there will be mating and pecking order drama. Very often the little drakes will be best of buddies as ducklings, grooming and snuggling. One day the mating hormones kick in and the duck drama starts. Even if they don't fight to the point of serious injury, they will spend much of the time chasing off the other drakes from their hens. Hens often only want to be with certain drakes, lots of running, chasing , grabbing, protesting, flapping and crashing around will be common. It can end up being a stressful environment unless you have a large area so everyone can spread out. Now if you had 8 hens and 2 drakes.....that would be a much better senerio. Hope things end up working out well for you.