The beavers are back!

Many thanks for the appreciation shown for yesterday's Northern Lights blip. I'm so happy I was in the right place at the right time, and had a chance to share that natural beauty on Blipfoto. Now back to today...
It seems an age since I did a long local walk so after a few days of garden work I decided today was the day. There's a circuit through the forest that takes about 3 hours to walk and that was my goal.
About 45 minutes into the walk the path passes the broad marsh you see in the blip. At the downstream end of the marsh the stream flows into a narrow valley with steep sides. Any engineer would instantly see that point as a good place to put a dam, and beavers are excellent engineers!  So there's always been a large beaver dam here. What is a little sad is that every few years someone (the landowner I guess) blows a large hole in the dam, which drains the lake you see here and effectively kills the resident beavers. However, every year a new crop of beavers have to go prospecting for new territories, and it's never takes long for new beavers to find this ideal spot and start rebuilding the dam.
The last two summers there were no beavers, and therefore no lake here. I was very happy to come back this year and find the dam renewed and this small lake in place.
I think over the next few summers the beavers will instinctively raise the dam and the lake will steadily increase in size. The extra shows the potential size of that lake.
The rest of the walk went well and I noticed a few changes since I did the walk a year ago. Two large tracts of forest have gone and one section of the path is being used a lot less and in another couple of years will be too overgrown to use. We live in an everchanging world!