Down in Westwego (southwest NO) a couple of years ago, the shipyard workers told me the nutria (think of a rat crossed with a rabbit) were digging burrows into the earther levees, weakening them. This may have contributed.
I knew they were good for nothing...:-) That's amazing to hear they might do that though. BTW... I'm from the area and am quite familiar with the critters. Used to run into them when I ran barefoot through the swamp (in my youth, of course).
"It's a Dark..Eerie..Lonely..Scary..Depressing and Dangerous Place".
It's a Dead Zone, IMHO.
sw
In central New Jersey I live very close to a historic canal, the "Delaware & Raritan Canal" which is 66 miles long and was constructed between 1830-34. The canal is built along the banks of the Delaware, Millstone and Raritan rivers. One side of the canal is dug into the hillsides and the other side is a levee wall.
When the canal was in operation, the canal company employed full time "ratters" whose sole job was to trap muskrats in the canal. Muskrats would dig burrows into the canal walls which wasn't a big deal on the hill side of the canal but could lead to leaks or structural failure on the levee side.