I have seen on a number of occasions where an otter has balled up a wad of grass into a neat pile and then use it for a toilet. The wad would fit inside of a ball cap, maybe a little bigger. It usually occurs where an otter had to cross over a path to continue on their way down the stream. There are no beavers for 100 miles and I have never seen any muskrats in this area. I wouldn't expect a muskrat to do this anyway, since it is high and dry about 10 feet above the water level.
Anyone else ever see this?

Odd indeed.

I've seen it quite a few times. They scratch just like a dog or cat and must get carried away sometimes.

That is NOT odd otter behavior. Otters have been doing this since otters became otters.

But why? That's the odd part, hence the question.

Simply amazing.

Too hung up on why. Not when and where.

The question was has anyone ever seen this behavior. Down here there are otter crossovers that have 2 or 3 dozen piles of leaves and pine straw raked up and dumped on in a 15 feet square area.

But, as to why they do this: it's part of their marking behavior. Sorta like when a canine kick scratches or a buck deer makes a scrape.

I'm guessing you haven't seen it either?

That makes sense right there. Thank you.
BTW, I trap all over the place all year long and I have only seen it a few times around here.

I find um hear alot there defonantly marking behavoir traits they pick up in frequency closer you get to breeding from what I've seen, But I find um all year long!!

Yep

you mean like this?