Scene of last four photos but taken 40 years ago

This photo was taken at the same spot as the two above it and of the same scene but it was taken in November 1969, 39 years ago, and it shows the beaver dam where it is today. So, again, this is documentation of the flux in the way the beavers have tried over four decades to control the flow of water along the floor of this lovely valley. For whatever reason, or lack of a reason, they have changed the rate of flow and the depth of the water myriad times. The fact that there is probably, by the most empirical data, no beaver activity at the current time does not rule out that they will return in the future and that the water flow in Zealand Valley will again be subjected to their engineering mania. The thought is, from purely a natural history perspective, that their efforts really contribute a kind of random, loosely knit, impact on the valley. It is a history not so much about the beavers, but about the water and how it impacts the valley. They are the change agents. By slowing down the water flow, impounding it so it widens itself beyond the normal stream bed, extending outwards on either side, the beaver have irrevocably changed the valley and added something significant. They have markedly improved the soil here and, by that achievement alone they have made it a more hospitable environment for a diverse plant community that, in turn, protects the soil.