Realy, it is Illegal?

Is a canada goose feather i found on the ground, during molting season illegal to take, i've used several in fletching. If so, why, I doubt there gonna need the molted feathers. Correct me if i'm wrong but taking a molted feather is not gonna kill a bird, its not like you have to kill a goose to get it's feather, just wait till early-mid summer (June-July sometimes August) during the molt.