A fully mature Muscovey drake will develop a line of red "mini crauncles" (for lack of a better term) down the back of his neck and feathers sometimes become almost curly looking around it. I have more than 284 (at last count LOL) Muscovey they all live together forming their own groups and I have never in the last 16 years lost a duckling to a drake. Now that is not to say the drakes wont put the babes in their place from time to time, but that is the normal way of life!
No all my male birds tend not to be too mean to babies but I have had females brutally injure baby birds.