Sharks and Other Marine Creatures
There are lots of sharks in the world's oceans, and most of them are relatively harmless. A large number of species can be found in Hawaiian waters, but shark attacks are rare. However, it's good to know that some of the more aggressive sharks, like the tiger shark, tend to feed at dawn, dusk, and at night, so the possibility of an encounter is more enhanced at those times.
Sharks tend to get a lot of attention, but there are a few other marine creatures out there you might wish to avoid:
Stay away from fish with spines. The ugly, spiny scorpion fish is poisonous, and the needlefish can poke you with its sharp nose.
Don't feed the fish; you might get a lot more attention than you'd like. Some will swarm like bees, some might not recognize where the food ends and your hand begins, and others might just be put into an obnoxious snacking mood.
Moray eels are big, thick snake-like creatures with a mouth full of sharp teeth. Try not to touch these guys. They live in the rocks, so it's best not to stick your hand into unknown places. Octopi also tend to hide in the rocks, and although they are relatively harmless, they have little beaks that can bite if you grab them.
Sea urchins cling to rocks and have long, typically purple spines. Watch where you're stepping, and stay away from them!
Some creatures with tentacles can sting. Beware of jellyfish, for example. If you see them in the water or washed up on the beach, it's best to stay away. The famous Portuguese man-of-war occasionally makes an appearance. This creature looks like a puffed-up jellyfish with long dangling tentacles, and it's especially nasty. If you see little flowery-looking things on rocks in tidal pools and elsewhere, you've likely discovered some sea anemones. They sting, too.
FAST FACT
The long, skinny, silvery fish known as the barracuda lives in Hawaiian waters. It has very sharp teeth and is known as a biter. It is especially attracted to shiny objects, so leave those sorts of things on the beach.
If you've been bit, stung, poked, or otherwise injured by one of these creatures, seek medical advice from the lifeguard or other local sources. Open wounds that you get in the water can easily become infected.
