Mallard Drake Stuck in Eclipse Molt

[Tay's Ducks]

Attached below is a photo of one of my mallard drakes. As you can see he is still stuck in eclipse molt. My other mallard drake has a bright green head and his feathers are a really pretty silvery color. Why is this one not molting for the bright plumage?

 

[chickens really]

How long has been in eclipse?

 

[Tay's Ducks]

How long has been in eclipse?

So we got him and the other mallards last year in April when they were all still ducklings. Towards the end of last summer he did start to turn a little bit more silvery on the sides, but in the winter he completely turned to what he looks like now and has been that way since.

 

[chickens really]

He will molt soon..Or that could be his colour too?.
I'm thinking he will molt here soon..

 

[Quacking Pigeon]

One of my Mallard drakes hasn’t finished moulting yet too. His dad is almost finished moulting. Some of them just take more time then others.