Too bad you don't have a picture, since today is "Identify the poop" day in the HH. :~) Well, I happen to have seen a lot of otter poop on our dock in summer. It's a little like a small dog's but with lots of small bits of shell and bone in it. breaks up easy as it dries out in the sun, not cohesive at all.
We went walking out there again this afternoon and we did see coyote poop. It was all hair.
Okay, WHATEVER YOU DO, Nobody ping g'nad!!!
I Googled "iguana droppings," but couldn't find an image. Plenty of mention, such as the fact that you sometimes see blood in it, and that it carries salmonella, fwiw, but no image.