The runners are going to need a step-wise program to help them. How long have you had them?
If they have not had access to swim or bath water, their feathers are likely not in good shape.
Do you think the other ducks might suffer bravely through for a couple of weeks so that the runners don't die?
I would first check each duck's preen gland. It is an inch or so from the end of the tail. If it looks crusty or swollen, it cannot work correctly. Some have had success massaging olive oil into the gland. It is very good for the skin and is soothing for inflamed tissues.
I would gat ahold of a swim pan, something about 8 inches deep, and large enough for at least a few of the runners to get into it at a time. Either have a ramp into and out of it, or smooth stepping stones, because at first they may need quite a bit of help managing. They have much to learn.
I would fill the pan, and toss favorite treats into it. Fresh garden peas, strawberries, whole wheat berries, for example, may entice them in.
Give them time in water then can stand up in, so there is no risk of drowning. Once the first one or two figure it out, the rest will follow.
I would not under any circumstance force them into the pan, by the way.
If you can set up a barrel or sprinkler so that they can stand under fresh water, that may help them clean up and start preening.
Another possibility is they could have mites that have messed with their feathers. Take a look. I have been told some mites are tan colored.
And please keep us posted!!
