Synodus foetens
Size: to 18"
Habitat: almost anywhere, but favors shallow waters
Notes:
You will find these at night in the river, perched on their fins, with alligator-like jaws studded with teeth waiting for some unfortunate killy to come by. Spook it, and the Lizardfish will dart away too fast to see.
I have found no correlation between good visibility and anything else at all. Calm seas certainly don't hurt, but the worst visibility I have ever been in was with a 1-foot surf on the beach. There is however a very good correlation between bad visibility and storms, which is why a single hurricane can end the season.
Other factors which influence visibility are: algae blooms, spawning seasons of some invertebrates, which can fill the water with tiny swimmers, jellyfish ( yes, so many you can't see through them, luckily they don't sting, ) other divers churning up the bottom, and just plain gunk in the water. I don't know how to predict most of these, except to say that if you dive a lot, sooner or later you will see some good visibility. Sometimes in the ocean, the visibility will be different in different depth layers. I have seen the viz go from 3 ft on the way down the anchor line to 20 ft on the wreck.
More: Visibility ...
