So...Drake or Hen?

We have several Rouens, a pair from last year and 6 newbies from this year. Most are quite easily sexed, however, there is one that causes question to us. It is the size of the drake, acts like a drake as far as 'leading the flock' but the coloring is all wrong. It has a partial ring around the neck, no curly tail feather as a drake has, minimal green coloring on the head and the body feathers appear to be brown/black mottled colored as a hen would be. The legs are a bit brighter in color than the pic shows.

Any suggestions? We will need to thin our drakes and wouldn't want to get rid of a nice drake if not necessary. Thanks for any insight, as I am relatively new to raising ducks.

Peggy

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