Ok, so it wasn't really snorkeling, all I had was my swimming goggles (actually they were my wife's swimming goggles, shhhh, don't tell her!), but I had my first 'snorkel-like' experience in a native river yesterday .
My wife bought me a pair of creekstomping shoes for Father's Day (closed toe sandals) and drove me out to the Little River Falls near Fort Payne Alabama. I didn't have my nets with me, so I just went swimming with the fishes. I stared in the shallows, with very little water movement. Everything was covered with some grungy algae stuff, and I didn't see any fish at all (I was standing up at that time). I ventured closer to the shore, and eventually spotted a few fish, so down into the water I went. After I lay still for awhile I noticed more and more fish... not sure if they were always there or if they just came out when I stopped moving. I watched a pair of small fish for awhile, then moved over to a depression where I saw some sunfish. The sunfish slowly became bolder (or I became more observant) and eventually there were close to a dozen sunfish, the largest of which had red on their belly. At some point I noticed some tiny little minnows. There were a bunch of them, and the school swam around right in front of my face. They were quite pretty, exhibiting some iridescent color which surprised me given their small size (about as big around as a toothpick, but maybe half as long). A predatory looking torpedo shape fish also cruised by, I'm thinking he was a bass. I guessed smallmouth at the time, but I didn't see smallmouth bass on fishmap.org for this basin, so I dunno.
My wife called me over to a deeper pool where she saw some bigger fish, that looked like 'catfish'. I floated in that pool for awhile and saw several more of the bass (including a larger one, maybe 10" long). They didn't seem to be afraid, but they didn't act curious like the sunfish either. Eventually the 'catfish' came out, and I'm pretty sure based on some image searching that they were Alabama hogsuckers. Those were cool fish, but much more skittish. They camouflaged pretty well in the nasty stuff all over the rocky bottom. I also saw a fish that was similarly shaped, but silvery colored. There were a pair of them, but I only saw them briefly and only once. Some image searching of species in the fishmap list leads me to believe it was some sort of redhorse, but I have no idea what kind.
The environment was surprisingly rocky, with almost no dirt, gravel, or plants (just a few plants growing up out of the shallower spots). Given that it was just upstream of the falls though, maybe this shouldn't be surprising. Down closer to the falls some of the pools had gravelly spots where water was cascading down, but upstream where I was focusing my attention (mostly because there were people close to the falls) it was just slippery rock.
In the smaller pools down closer to the falls with moving water I saw a number of darters, along with other small fish that were similarly colored but weren't perching on the bottom. I also saw a BUNCH of what looked like little tadpoles, but also a tiny little fish that was fat like the tadpoles, but it had a fishy tail instead of a tapered tadpole tail.
No camera, so I apologize for the lack of pictures, but I had a lot of fun, and was really surprised by how interesting this little stretch of water was. I definitely need a snorkel before I go back -- In order to minimize my movement I would have to touch the bottom to lift my head to get a breath of air, so eventually I stirred up a bunch of the gunk and it got harder to see, not to mention that I couldn't really float motionless for very long.
My wife probably thinks I'm crazy... she was taking the dog to play in the water while I was just floating in shallow water with my face under, but it was a blast!