Pond Boss Forums INTRO Questions & Observations Dam management

My 45 year old 4 acre lake in East Texas has many tunnels in the dam throughout the area above water. I am pretty sure that it is beaver, but locals say it is most probably nutria. Is there any surfire way to tell the difference? I know beaver are there, I have actually seen them, but not the nutria.

Secondly, Opinions welcomed about my plans to repair dam. Using a backhoe, we are going to collaspe the tunnels and backfill. Then regrade the top of dam and water side. I am thinking, that even if I get rid of the critter problem that they'll be back, so I was going to line the water side of the dam with used 6' tall chain link fence. Any thoughts on this method?

Thanks to all who respond!

Jomo,

Noticed you have a low registration number but few posts...welcome back to posting.

Beaver leave unmistakable signs of their presence by the harvesting of nearby small trees and such. Generally their homes are also visible partially above the waterline.

I'm also in East Texas and we have had a continuing battle with nutria. They are incredibly harmful to your dam digging numerous tunnels which undermine the integrity of the dam and cause significant leaking.

Repairs can be difficult depending on how long they have been present. I've tried front side repairs (didn't work), back side repairs (didn't work) and finally repair by going through the dam from the top side with a back-hoe. I believe this has worked, but won't know for sure until the pond refills. I cut a trench about three feet wide along the dam all the way down to the depth of the water. I found places where the water was flowing from front to back because of the nutria. I found numerous places of pine straw pockets and stuff like that 6 feet down in the middle of the dam.

Lining with chain link fence is a novel idea. I think it would work if you have complete coverage. However, the nutria will also tunnel into other areas as well as long as its close to water. In this old pond, they had established homes opposite of the dam also in just regular dirt. Bad critters, very bad.

In my case, since I was rennovating the pond and expanding it, I should have just started over completely on the affected dam segment. It would have been easier.

Nutria do not like to be disturbed...the more noise you make with equipment and such and the more human presence the less likely you are to have them around.

Keep us posted.

I would listen to ML on this one. I have repaired some nutria burrows and am waiting on some rain to raise the water level to see how it holds. I usually don't see nutria except at night or early in the morning. Biggest sign of them is vegatation mowed down or their waste.

Good luck.

TEXAS715,

That's an excellent point about the vegetation. When nutria are present, they leave very telling signs of partially eaten grasses in and along the waters edge. Dead give away for Nutria.

ML,
Would muskrats do the same thing? I have just assumed that I have muskrats since nobody in my area seems to have heard of nutria. What are the differences? I have noticed some floating cut grass along the edge of the water and wondered how it got there. I have lots of burrowing going on one one side of my pond, but none on the dam or on the other side. Pond is leaking pretty bad(inch a day). I tend to think poor soil in the main basin is the main culprit, but the burrowing can't be helping.

Coach,

If you were further South, I'd say you just described Nutria...floating grass, burrowing, leaking pond, etc.

I haven't encountered muskrats since I've been in Texas and so can't help you there. However, if there was something burrowing in my pond, based on what I've seen of the damage that can be done, I'd sure get after it.

Coach,

Yes, muskrat behavior is pretty similar. From the descriptions of the nutria, it sounds like muskrats are a bit less destructive but they are certainly capable of causing a leak. Especially if the dam is not as wide or strong as it should be. Muskrats, will cut grasses, small saplings, golden rod, etc that are growing close to the pond and carry them through the water to their den. They often leave a trail behind.

I don't have dams on my two ponds so there is no worry there but the rats are starting to wear out their welcome. I was trimming grass around one of the ponds the other day and counted a half a dozen rat holes with more in progress. I'd like to wait till the fur primes up and trap them out but they certainly are beginning to leave their mark.

Russ

I've had beavers in my creek. Some of them build a dam of sorts and others just tunnel into the bank. Both do a lot of tree damage. They seem to last until the coyotes and bobcats finally get them.

Thanks for all the feedback guys. I guess I'm fortunate that my pond/lake (it's 5 acres!)isn't leaking at all. Occasionally there is some floating grass and reeds, but not so much that it covers more than 5 sq. ft. altogether.

We are going to attack the dam from the top and collasp each visible area as we come to it. Then fill with excess material and clay. I'll have the fire power ready in case we chase out some critters.

I'll keep ya'll posted on progress. Meadowlark, if you don't mind, email if you can schedule a trip over to this lake and do an assessment. Thanks

Robinson,

Sounds like it would be worth a try. Kind of the same principle as leaving a sheep dog with the flock.

Nutria are mostly nocturnal, however. All dogs I've ever had like to sleep at night....and the day time also for that matter. If you could get the dog colocated with the pond 24/7 it just might work.

I have a lab and a pointer. They are in at night mostly. My neighbors dogs (3) do a lot of hunting around here and have never caught a nutria, they do catch armadillos, coons, rabbits, etc.

Nutria's are mainly out at night, are usaully in the water and can spend a long amount of time under water to avoid trouble.

Now my lab is great when we go out in the boat to hunt for them. He will get on the bow. If I troll around slowly all I have to do is watch him. He sniffs them out and I take the shot.

I've been told the only way to controll their pop is yourself or get an alligator.

Good luck

Thanks for the suggestion.

At the rate its dropping I may not have to siphon it at all. We were really hoping the inflow from the spring would offset the questionable soil content. It did not. Luckily, the builder is a reputable family friend who will do all he can to fix it. At this point the plan is to drain it til we can stockpile enough suitable clay then spread and compact the snot out of it.