I've never seen beaver build under a man-made structure. They prefer open water in areas not disturbed by human activity, esp boats.

I would think that it is more likely to be a muskrat. They are a similar colour to a beaver but not nearly as huge and with a slim tail instead of a paddle. They swim with a wiggle very quickly, submerging when they feel threatened or to dig up marginal plants like reeds. They will then haul the entire stem to a floating woven mat of vegetation to eat the tender roots. Muskrats are not aggressive at all unless cornered - their main defense is spraying, faintly reminiscent to the skunk. More likely, you will have to protect them from your dog.

The other possiblities, although unlikely, are a mink or an otter. You would be very intimidated by the former (nasty little creatures) and charmed by the latter.

Would a barrier of heavy duty hardware cloth be possible?

Then I am stumped - that is very odd behaviour. Especially as you say there are no other beavers nearby, so there is no family group or overpopulation pressure. The fact that he is hanging around human habitation in the daytime and not slapping anymore means that he does not perceive you as a threat anymore. I might question rabies in your neck of the woods.

In my long and continued experience in Northern Canada, once a healthy beaver has staked out his territory, he will denude the shoreline within that boundary of all desirable wood. They are very stubborn and will not be dissuaded! At my last cabin, I eventually cut down all the remaining poplars and left them near the water for the beaver to take. Better that than let my dogs go after him when he was vulnerable on land. Once the beaver knew there wasn't anything more he wanted from my property, he and his family moved on so to speak. Stayed in the stillwater corner of our bay but always remained an integral part of the landscape. That beaver was the only one with whom I ever had a problem.

You could shoot him but why? You are the "intruder". And if you trap him and he is relocated, he is at great risk of being killed by another beaver upon whose territory he has encroached. Or he might just find his way back to his own home lodge. You could also try and blow up those dam lodges with dynamite. Invariably though, the rebuild starts the next day. Another option is to trap and skin him for his pelt, part of the culture where I lived but never one to which I ascribed.

A further caveat. If he is chewing on pressure treated wood, he is at risk for arsenic poisoning. I would protect him - and my dock - by wrapping a few layers of heavy gauge chicken wire around the posts.

If you are really concerned, you should contact DEP or Natural Resources in your area. Me? I would just watch and see what happens.

First off I haven't walked around our twin lakes to see if he does indeed have a main home lodge. Second I am in an urban area so to speak, neighbors close by, so I think dynamite is out of the question. We are however surrounded by 900++ acres. Plenty of wildlife!
I will try all things before I call DEP. During the winter our lake water level is lowered to control milfoil so he will have to go to the upper lake in order to have substantial terrain. All of the shoreline will be exposed. I will try and do the fence thing. I will keep you posted!
Thanks for the insight!

Hello,
We also have a Beaver under our dock building a den which he started 10 days ago. We are located half way on a 22 kms lake, lots of people, dogs, docks and boats. No one has seen Beaver Dens in this lake before. He is building his den under a removeable alumimun pontoon dock with plastic treks decking. So can't eat it, but making a big mess all around it and under. We pull this dock out every fall, so we are a little concerned. Not sure what to do, but he is busy. Why he would pick our place is very weird. He is for sure a Beaver, and was slapping his big flat tail at us the first day. Any suggestions out there? Do Beavers get aggressive with children or pets?

Beavers are sooooo persistent. We have a large creek running through our property and had big problems with them for years........coming up over the bank and into our yard and eating our trees. But they are wonderful animals! And they are great parents. Its a real philosophical dilemma as to how to get rid of them.
We ended up using smoke and cherry bombs around their dens which did seem to scare them away.
How about keeping a radio turned on 24/7 around your dock?
Too bad you can't keep a dog there all the time.
I recommend chicken wire or hardware cloth around the legs of your dock. We had to wrap many of our trees like that along the creek. Fortunately, the creek has been low for several years, which has helped alot in keeping them away.
Its pretty hard to live in harmony with these little guys, but I hope you can figure out a way. Like Adrien above said, you/we are the intruders.
Good luck with this challenge!

Hi gang,
I was amazed when the stinkers moved in under my dock.
They truly are mess makers and have no respect for property but I cant help admiring them and their persistence. My dock is very old and time for replacement is near but when the beavers started chewing away at the sides and piling the crap on top of the dock, that was it. This means war! For weeks I would clear out everything they stuffed in and on top of the dock looking for ways to get rid of them. The neighbors suggested the only way to be rid of them was to shoot them. No thanks, not up for that.
I tried almost every product available but to no avail.
My dear wife came up with the idea of some very smelly deodorant soap. What had I to lose?? I bought some Irish Spring bars and using a cheese grater, shredded them up and filled a couple of small yogurt containers, placed them in the den one night.
2 days later, no beavers, they are gone!!!
And I didn't have to shoot them to my relief!!
May have also helped that I also took the liberty of taking a leak over the den every night.

Beavers definitely built a shelter under my dock. Definitely a beaver. I’ve lived in the lake for over 20 years and have seen tons of muskrats. And a few otters. No minks. I’ve seen our beaver personal and up close.

I truly understand the frustration with beavers. But I also know that humans have taken over/destroyed so many other species' habitats. It's hard to deal with, but we really must try to somehow live with them.

We have had the same advice- shoot them. I don’t mind them but they can’t stay under the dock. They cause too much damage calling professional removal is pretty expensive. Looking for ways to drive them out without arming them. If they weren’t so destructive I would like them to stay.

How about a light on directed to under the dock at night? A radio on all the time?

I have beavers under my dock. They are there. Their babies are their. They come in in early morning & out ever evening at dusk. They built a den on top of our dock and are damaging our styrofoam panels that float our dock. We are still burning all the twigs and there are tons more. Trapping means they will only come back as they are many of them. We are going to take up our boards and they and clean out mess as we have tried coyote urine, repellent ($140). we need them gone. Destructive!

We have beavers under our concrete dock they bring all their debris stuff it where it has cracked open. When the lake gets high they have a nice little den under the stairs. I just purchased a plumbers scope and will snake it up to see where the den is. I also have coyote urine which I will stuff inside. Once out hopefully we are going to have the dock protected with fencing done by folks that deal with Beavers. It’s a pain you can trap them but other beavers will come. In our area the only people who are authorized to relocate beavers is the Tulalip tripe. It’s a difficult animal to have as a roommate they are very destructive good luck