Funny you should mention ticks. I've had to remove 2 so far this year from around duck eyes. That's the only place I've ever seen/noticed them on any duck. They have been on my special girl on her "bad" side twice. She has a special leg, which makes it difficult for her to properly scratch/preen one side of her face. That was the side the ticks have been on. Other than that, ducks are really good at preening away/eating ticks so they don't usually present a problem for them.
I just used the same tool I used to remove ticks from dogs, where you kind of grab it and twist them until they let go. Pretty easy, but a delicate process when it's right by their eye.