Monday, February 4, 2013

I bet this beaver really, really, dislikes urban sprawl (Or that dam damage)

The remainder of the dam.
I checked the dam again this week, and was saddened to see it decimated by a flood. Compare this picture with last week's, and you notice that the dam is much lower, and the pond has lost a great deal of water depth. You might also note that the food cache, visible in the center of the stream in the background has been reduced dramatically. More on that later.










Another view of the depleted dam.
Another view of the dam, or what's left of it.














The larder is nearly bare.
Also washed away in the flood was perhaps half of the beaver's food cache' maybe even a little more than half.












Soil washed downstream by the flood.
Before it washed away, the dam must have held back a considerable pool of water. You can see soil that was carried down in the torrent, and left behind when the water slowed behind the beaver's dam. The dam is visible in the upper right of the photograph.









A check of the water flow data in Minebank Run will tell us when this happened. Check the chart to the left. Look at that flood!

(Perhaps you'll allow me an unsolicited editorial here? That chart is the work of the United States Geological Survey, an agency of the Department of the Interior. They do fine work. We shouldn't cut their budget, or sequester it.)



That flood is a direct result of impervious surfaces such as roofs, roadways, parking lots, driveways, et cetera. Instead of hitting soil, and percolating its merry way into the water table, stormwater and melting snow speed their way into the nearest streams. This is the cause of so much erosion in streams near urban areas. The water carries with it nutrients, fertilizers, pet waste, pollutants and trash. All of this eventually ends up in the Chesapeake Bay. We don't want it in the Chesapeake Bay, do we? (http://www.chesapeakebay.net/issues/issue/stormwater_runoff#inline)

the cover of the den's vent hole.
Before it has a chance to pollute the bay, this stormwater also damages the homes of our rodent friends, the beavers. This beaver set up housekeeping very close to Towson. The only thing left undamaged by the flood is the roof of the beaver den's vent hole.








I checked the camera four days after the flood. I checked the slides on both sides of the stream, looking for evidence of beaver activity. I'm sorry to say that I saw none. I don't know if this means that the beaver has packed up and left, or perhaps is waiting for things to settle down.

The trail camera again failed to record the beaver. It also was damaged by water. Thanks to www. trailcampro.com for fast and helpful service with returning it. I'll have it back in the field soon.

More later.



No comments:

Post a Comment