The Bella Coola Valley has a fluctuating population of beavers which I think depends on predators, trapping activity and the amount of good feed (willow being the most preferred) and general weather and water conditions. In a few of the ponds and back channels that they inhabit you can find the occasional classic beaver house made of sticks. But it's more common to see them in slow moving areas of the Bella Coola River where they seem to get along really well and they become "bank beavers", building houses in soft mud banks which must make for quite comfortable living.
It must be a good way to go because they have lots of ability to move up and down the stream looking for food as long as they don't pick a place that dries out in low water or get picked off themselves by a lucky grizzly bear. Grizzly