Dark Green Spots on Duck?

[Jaeden0720]

I noticed yesterday evening that my male Pekin Duck (Aflac) had dark green spots on his beak. I was wondering if this is normal? Should I be concerned? He has always been a healthy big duck. I've been feeding them (and my other female Pekin Duck) 16% layer pellets. I got the feed from Tractor Supply. I am new to raising ducks so help would be much appreciated! Here are some pictures...

 

[Isaac 0]

That is normal pigmentation, nothing to be concerned of.

 

[Jaeden0720]

That is normal pigmentation, nothing to be concerned of.

Thanks!!!