Judging by the change in the landscape around the creek that drains into Lake Vadnais, the beaver there have indeed been very busy this past fall and winter. A maintenance crew came by in the fall to pull downed trees out of the creek, but the beaver have chewed through most of the remaining aspens that line the banks creating this scene.
I assume they harvested the smaller branches of these aspen for their winter food storage. Those amazingly sharp incisors cut through trees 12-16 inches in diameter. I wonder how long it takes a beaver to fell one of these trees — can they do it in on night?
I noticed footprints of what might have been beaver in the path so I followed them back to their lodge.
Clear footprints of a path going to and from the lodge over a thin icy crust of snow on the frozen part of the marsh. The front foot looks almost like a handprint, the rear foot has elongate toes with webbing between them. (The toe of my boot for size comparison.)
Footprints led right up to the back door entrance (on the backside of this view) from the woods. The lodge hasn’t changed shape much in the past two winters — no new material has been added to the top.
An artist’s (Jennifer Garrett) view of what goes on in the beaver lodge during the winter (imagine that’s me up there on my skis). Photo from Jon Nelson’s blog post on “life under the ice“.
Entrance and exit tunnels from the lodge take beaver out to deeper water in the marsh, as well as exits onto land where they can continuing foraging (and felling trees, I guess). One adventuresome pair of skiers caught a beaver that had just emerged from one of those tunnels into the bright glaring snow scene.
If food supplies run low in the lodge, the beaver can always run out and harvest a few branches to snack on. The problem is getting that bulky branch to follow them through the icy water and back through the tunnels into the lodge. Photo from Bob and Jean’s blog: frame to frame
I don’t think there is any other animal (other than humans) that modify their environment to the same extent that beaver do. By impounding water in larger pools, they create a safer environment for themselves, and change the habitat to become more suitable for many other wetland species as well.