November 02, 2008
They've managed to flood the lawn in the west side of the apartment.
This is the park, about half of which is flooded by the dam in the foreground. The county planted all those saplings, but if they spend all their time flooded like that they'll die. So I suspect the county will be back next week, and maybe they'll be smart enough this time to haul the debris away, instead of leaving it handy right there for the beavers to use in rebuilding.
They did all that in two nights, so they really must have been working.
I know the dam doesn't look all that impressive, but the pond they created with it covers more than half an acre. As an engineer I respect economy. Getting big desirable results from small effort is an indication of good design. And flooding like that is desirable, from the point of view of Beaver Engineering Inc. (And the ducks like it, too.)
But probably not from the point of view of the county, who don't want all their trees killed off by stupid meddlesome rodents.
This the culvert I can see from my deck. With the dam gone, the water level is down near the bottom of those concrete pipes. Off in the distance, on the left bank, you can see a black stump sticking out sideways. When we got the mondo flood two years ago, the water was that high.
Just to give you a feeling for how those pictures relate:
The arc in the lower left corner is where the dam is. The blue line indicates the area they've managed to flood. Each number is one of those pictures, and the lines indicate the direction I was looking.
But as an engineer I find it hard not to root for the beavers.
Posted by: tellu541 at November 02, 2008 07:05 PM (pJ1uW)
If the county wants to keep the beavers from continuing to try to work there, they're going to have to do more than just rip out the dam.
The place by the culvert where the beavers used to work isn't an attractive nuisance any longer because the county guys came in with mattocks and dug out the bottom of the creek. There used to be something of a ledge there, over which the water flowed, and that's what attracts the beavers and makes them feel like working. Any time you have rapids between banks, that's beaver heaven. Once the guys dredged out the bottom and got rid of that rapids, the beavers lost interest in it.
They'll have to do the same thing over in the park, or else the beavers will be back.
I must say that I'm glad they're not taking the easy way out by trapping the beavers and getting rid of them.
Beavers are cool, because they're the only animal species besides ourselves who make significant changes to their environment for their own benefit. And they've been doing it longer than we have.
Posted by: Steven Den Beste at November 02, 2008 07:39 PM (+rSRq)
The water is up maybe another 6 inches today. It's enough so that the flooding in our lawn is larger. I went and looked at the dam, and I think I can tell that the beavers were working on it again last night.
I do wonder how long it'll be before the county guys show up for their counterattack. If the water rises much further, it's going to start threatening one of the buildings in the apartment complex to the west of the park. It's already covering the walkway that runs between that complex and the park.
Posted by: Steven Den Beste at November 03, 2008 10:56 AM (+rSRq)
Posted by: Siergen at November 03, 2008 05:35 PM (+JsQ3)
The county isn't taking out all their works, just the ones that cause trouble. The beavers need at least one pond for their lodge.
The pond isn't a food source for the beavers, it's transportation and protection. They go up on land to find vegetation to eat, and I think they can survive with just a stream. The main problem in the wild without a pond is exposure to predators, but there aren't a lot of wolves or mountain lions or bears in Beaverton.
I don't honestly know where they're living, but I do know of one of their dams that the county is leaving alone. It's been there since I moved back here two and a half years ago. I'll take a picture and post it sometime. I wouldn't be at all surprised if that is where their lodge is, but I haven't seen it. By water it's only about half a mile from my back yard. (By sidewalk it's a lot closer; it's a different branch of the stream.)
Posted by: Steven Den Beste at November 03, 2008 06:24 PM (+rSRq)
Enclose all spoilers in spoiler tags:
[spoiler]your spoiler here[/spoiler]
Spoilers which are not properly tagged will be ruthlessly deleted on sight.
Also, I hate unsolicited suggestions and advice. (Even when you think you're being funny.)
At Chizumatic, we take pride in being incomplete, incorrect, inconsistent, and unfair. We do all of them deliberately.
21 queries taking 0.0435 seconds, 22 records returned.
Powered by Minx 1.1.6c-pink.