I wonder what they are eating now?

In a pond I once had with muskrats I believe they ate cattails. They certainly used cattails to make their homes. I had cattails before the muskrats moved in, so they could stand the harvesting.

You could try planting a lot of cattail all over the place and hope some last long enough to get established. Probably best to plant where the muskrats won't look first, like on dry land and then water them and let them spread down to the water's edge.

Plan B would be to fence in the plants and that means either putting the fence far down into the ground and/or containing the entire root ball plus a foot or two above ground. But expect some loss.

Willow might be another choice.

Keep in mind that more food means more muskrats. They are territorial but still. Plus more food allows for larger litters and more often. Depends on whether you want to promote their numbers or limit them.

Also, muskrats, over time, will fill in a pond to some degree. All that dirt from the tunnels ends up in the pond, banks break down. The loss of depth will vary of course.

Hey Keith, I love watching muskrats when they come to play in my pond. They preen and posture and swim laps, lots of laps. They seem to like the underwater lights. I have never had them destroy plants or chase the fish the way raccoons do. But my pond is only a thousand gallons so it wouldn't do as a home the way yours does. When we lived in Wisconsin, my friends who lived on the lakes had to set traps for them since otherwise they would have lost their back yard. I found lots of sites that discussed how to get rid of them but nothing about living with them, I'm sorry to say. The following is what they like to eat and it sounds like they will chow down on just about anything. The entire link is at the bottom. Good luck. Sandy

"Muskrats are primarily herbivores. They will eat almost any aquatic vegetation as well as some field crops grown adjacent to suitable habitat. Some of the preferred natural foods include cattail, pickerelweed, bulrush, smartweed, duck potato, horsetail, water lily, sedges, young willow regeneration, and other aquatics. Crops that are occasionally damaged include corn, soybeans, wheat, oats, grain sorghum, and sugarcane. Rice grown as a flooded crop is a common muskrat food. It is not uncommon, however, to see muskrats subsisting primarily on upland vegetation such as bermuda grass, clover, johnsongrass, and orchard grass where planted or growing on or around farm pond dams"

Here is a link that might be useful: what muskrats like...

Thanks for all the advice. The ponds are quite old, at least 40 years, so there is plenty of established rush as well as many other marginals, that I believe the muskrats are eating. I wonder how often I'd have new residents if I moved those that are living in the banks now? Are they like chipmunks? I know you can never keep chipmunks out of existing holes. It's an ongoing battle. I assume the same will prove true with the muskrats.
I thin I'll end up trying the cage method with waterlilies, as I am desperate to have them. What do you think the chances of survival would be if I tried to distract the muskrats with quick growing WL or WH? Should I wait for next season to give this a try? Thanks, and thanks for the link.
---Keith