Snorkelers...Fish to be wary of....?
 

As a novice snorkeler, I am wondering if there are any/many fish snorkelers should be wary about? I have only snorkeled at Chankanaab Park, Cozumel, Seven Mile Beach,Grand Cayman & most recently, Coki Beach STT. At STT they hand out dog biscuits for fish feeding, which will indeed bring a crowd. I had my index finger gashed by a fairly good sized fish (possibly yellow tail?) It was simply making a dash for the food, & caught my finger. Since reading posts about feeding the fish, I realize this is not a good practice, however are there any good resources for safe snorkeling. I notice many making reference to seeing barracuda & keeping a distance, are there others? Any help will be greatly appreciated.

Most fish are more scared of you than you are of them. Obviously feeding fish in places where they are accustomed to feeding makes them less scared and more aggressive and your gash is proof of that - it is not a good practice.

Having said that, the only thing that I have ever heard - and I'm an experienced snorkeler and diver - is that barracuda can be attracted to shiny flashing objects, like sunlight flashing off jewelry. So the recommendation is wear as little jewelry as possible when snorkeling - which makes good sense anyway since you don't want to lose good jewelry in the water anyway.

Lots of coral not to touch, can't think of any fish besides Barracuda and don't step on the sea urchins :)

Good advice re: shiny jewellry and barracuda. They really are not a threat but it's very disconcerting to have something with big teeth nosing up to your ring finger (which happened to a friend who was flashing a giant engagement rock - after that she taped it over or did not wear it when snorkeling). Don't worry if you notice barracuda swimming parallel to you, they are just curious. NEVER touch coral - fire coral can be most unpleasant. Don't step on spiny urchins. Avoid moray eels - they can get aggressive - although it's mostly bluff.

I had an experience in Maui with little fish nibbling the residue of fish food off my fingers after I spread some around. I thought that was really special, so I held out a piece of bread, and a puffer got a piece of my finger along with the bread. I later learned that they don't see too well, but smell real well, and my finger got in the way. Since then I learned to spread the food really quickly, then retract your hands fast.
The fish do their feeding-frenzy thing, only a few feet away. But you might not want to tempt barracuda and eels is one is close.

Barricuda certainly are curious and they will follow you to see what you're up to. They are fascinating to watch. While snorkeling in Key West - which BTW has some of the best snorkeling around, I hovered above while a friend of mine dove really deep for helmet conch. He dove down and checked out the bottom and I noticed a large barricuda watching too. As soon as my friend came to the surface, the barricuda went to exactly the same places checking out what he had examined. The same barricuda did this more than once and also mirrored my friend's actions along side him at one point. At one point, we swam perpendicular to a big school of juvenile barricuda. Seeing hundreds of those sets of jagged teeth coming towards me was a little unsettling but they weren't after me.