Sounds more like the lack of oil in the feathers from not bathing. Also might be ready to molt soon..Give them access to bathing water and they will soon look better.Not 100% sure; however, they aren't dropping any feathers, so I'm assuming it's wet feather? They came to me with a brownish tinge all over them and the enclosure they came from was just dirt. It's Spring so their enclosure had turned off and on muddy. I had read that ducks that live in muddy conditions can cause them to get the mud/dirt all over their feathers. Mud is a natural oil remover, so I assumed that's what happened. They also did not have any place to bathe (which is hard to do over the winter), so when I brought them home, I let them have a bath. The water was filthy when they were done; however, an hour and a half later they were shivering and their feathers were still wet. I had to blow dry the drake (he was the worst off) with a hairdryer! He actually enjoyed the pampering! lol. Their feathers are much more ragged than the feathers of the 2 other rescues (I got them from a different location). Of course, the other 2 girls are only 7 months old, so perhaps that's why their feathers looks so good and are waterproof still? The two other girls are almost 2 years old and the Drake is about 4 years old.