It's ironic you use hot sauce to get rid of them, as it was the McIlhenny family of Tabasco fame who introduced them to the US where they have become a pest.
Never eaten them myself.
and I've eaten nutria. can't say it was the most delicious critter I've ever tasted, but it wasn't bad. plenty of spices and slow cooking ought to do the trick.
Very economical and doesn't require you to sit out there with a pellet gun.
After a bit of quick research on nutria specifically as we do not have these here in South Carolina yet (I stress yet) I think I have a better understanding of the problem and perhaps a solution. They are using the ditch as a highway and there is little that can be done about it. I think you will find them in the yard from time to time especially if you have things they like to eat in it. That said if they are living under your outbuilding either it is raised up off the ground a little bit or they have dug underneath the foundation (which can be real bad) or both. What you need to do is take a day and scare all of the animals from underneath the building (assuming you can). A short dog such as a dachshund can help with this (after all they were originally bred to go down holes for hunting). Then when you are at least 99% sure there are none under the building you dig a trench around the building (or the side facing the ditch at least) and bury some chicken (or similar such as hardware cloth) wire leaving some above ground to attach to the bottom of the building. This makes it more difficult for them to dig under it and prevents them from going under if it is slightly raised. Still while protecting your building should be top priority I like to make use of whatever natural resources that are presented to me and depending on what you read nutria is good eating if you get over the fact they are basically a giant rat. I personally would go the pellet gun route (although for a first try maybe my bow or even 22) and invite one to dinner just to see if they were good eats but even if not I would still reduce the population but then I enjoy hunting and shooting.
Can Anybody suggest what I might do about Nutria. I have some that believe they should live under my outbuilding in the back.They are very tame & brazen & just walk around the yard during the day like they are house cats. The adults are as big if not bigger than my dog. (He's a Pekenese) I've been told & tried the trick of putting a generous amount of moth balls in the building as well as down the hole that they come & go through but it seems to act more like rock candy for them. Tried putting Hot sause @ the entrences as well. The county came out & set some traps in the gully behind our fence last year but I never did hear of the results. I'm concerned that my grandkids or chickens or veggies will be attacked by them. I hate to have to get a gun even if it's just a pellet gun to ward them off but if I have no choice...
The only solution is setting off a nuclear device. hahahahahahaha Have you ever been to some areas along the Gulf Coast? I was visiting some friends in Pascagoula Mississippi and they took me to an area to show me the "Nutrarats." WOW! There certainly is a huge colony in that area.