Teach me about beavers that den in river banks. I have a friend who has a problem but can't seem to find where they are. How far will they travel from the den to cut trees? What should he be looking for along the bank to find them?

Ive never looked for dens around here. Only thing I look for is cuttings and active slides. When floods happen, i look for softball to basketball sized cuttings on trees.

During drought years the old dens are easy to find and if you aren't worried about snakes an interesting thing to explore.

Most of the beaver where I trap are all river bank dens. They can and will travel a long way man, they are really smart and just when they are looking for something will travel to find it. You need to be looking for consistent feed piles and you will likely see a series of dams that make no sense to you or me, but they know exactly what they are doing. If those bank dens are anything like the ones where I am trapping, you just are not realistically going to be able to get a conibear in front of the entrance, it's 4-6 feet under water at an angle.

Normal methods to trap the beaver will work though include blind sets, castor mounds, dam break sets, water way sets, etc. I don't know about WI and river otter, but if you do any conibears, you will likely get an otter or two. Just saying. Goodluck.

Forget about the dens, and set where they travel. He will get them, just be patient!

Bank den beavers are all I trap. I look for areas they are cutting trees on the bank and make a castor mound with a 330.

What's the size and depth of the river?

I've seen only a couple of beaver lodges in my life. All the beaver that I pursue either live in bank dens or just in brush piles or briars. I rarely ever set the den itself. You tend to spook them and they almost always have alternate ways to exit the den. I set on recent beaver activity, usually mud pies.

Lots easier and more productive to find where they are using and trap them there. Any dams (often aren't in rivers) set the crossovers, any channels they have made/are using get a 330, castor mounds, etc. I tend to make a lot of castor mound sets when trapping river beaver, and a lot of blind sets when trapping pond beaver.

Most lodges here start out as bank dens,as the water rises and they keep adding on the outside and excavating on the inside while they raise the dam,the bank den becomes a lodge in the middle of the pond.
If you can ascertain where the original creekbed was (deepest spot),it gives you a good place to sound the ice to locate the main entrance.
Some older lodges can have 4 or 5 entrances but the main one is almost always wide enough for 2 or 3 traps side by side plus a couple more out in the run.When trapping a lodge you only need to set the main entrance since all the beaver use all the entrances both coming and going and you can catch a bunch with multiple traps at the main entrance only.

Around here they like to make bank dens under the rootwad of a tree that's half-fallen in. I assume the rootwad provides a break from the current and provides some structure, sorts like rebar in the mud, to keep it from collapsing.

Most all the beaver i trap are in big rocky rivers. Dams only occur sometimes on channels, but never and lodges isolated in a dam. The will make a lodge on the bank occasionally and those are sometimes easy, sometimes impossible. There is one i trap by that the entrance in is about 3 ft of fast flowing water. They chose wisely. 330 and such work at the pinch points and slides around root wads. If there are a few smart ones, the footholds get them pretty good. Drowners are sometimes tricky with the rocks. I look for deep water next to a steep bank or somewhere they have been feeding. Feed sacks with rocks are fast and light.

Thanks for the replies. The river has a max depth of about 6'. There are no dams or lodges to be found.

Bank dens are not hard to find around here. Beaver tunnel up and make a hole in the high bank so they have air. They will put sticks around the hole. Easy to find.

When I trap on a larger river I start by looking for cuttings, work your way down river and as you go you should notice an increase in cuttings as your approach their home area. Once down stream of their main area the cuttings typically end abruptly. My though on this is that it is easier for them to float cut feed down with the current than it is to drag it back against the current. Typically I will find a feed bed pile wedged in with a down tree and sometimes bank dens can be located around that. As mentioned above, I also like to set where they are already coming out of the water and usually sweeten the deal with a castor mound.

I learned one (among many other) things from an old time trapper on the main river I trap. Unless you want to catch a lot of kits stay away from setting feedbeds or foraging areas in the willows with multiple trails. Focus on the marking areas that are kept up by adults. When I started doing that my ratio of kits to adult really kicked in to my advantage. One year when I was keeping track out of my first 100 beaver catches only three were kits. The percentage is usually higher than that but that particular season I was trapping a stretch of river that hadn't been trapped by me or anybody else for over 7 years and adults made up a much higher % of the available beaver.

I believe part of that is due to beaver infanticide by the males.

Around here I don't worry about the den I use mb 750's and drowning rods with castor on travel routes along the banks