Critters at Hawaiian Dive Sites

To keep an underwater visit from turning into an unpleasant or painful experience, it always pays to be extra cautious; be aware of the not so obvious, especially if you are diving a site for the first time. This article is about potentially harmful sea organisms and not nearly complete, it just contains the ones that I saw the most frequently. Many of the poisonous critters are unfortunately also masters of disguise. Being surrounded by all those other colorful tropical fishes can be a lot of times a distraction and one can easily overlook and put a hand or foot on something other than a reef.

For me, top of the camouflage list is the Scorpionfish (try spot them in the pictures!). They have poisonous spines on their fins and back, which can deliver a very painful sting. Not necessarily needing to hide, they rest on the top of a reef or any object and can be easily stepped on or touched. An especially poisonous kind of this family is the Lionfish, whose vibrant red white striped body and featherlike appearance do not blend in, but rather should be a warning sign by itself. A good reason to watch where you step or hold on to; it can turn out to be useful also in regards to the abundant number of all kinds of sea urchins (tip from my own experience – also watch out where you kneel down).

White spotted Pufferfishes are cute to watch and sometimes come very close to divers like they are happy to pose. When feeling threatened though, they can quickly turn their body into the shape of a balloon by swallowing water. As its name indicates, the Porcupine Pufferfish additionally is covered with spines and can camouflage very well.

Eels tend to hide in crevices during the day, sometimes sticking part of their body out, their mouth wide open. This pose looks aggressive, but it is their way of breathing and they are usually shy animals. Another reason to take caution where to put your hand not only onto but also into while diving or snorkeling. Holes, cracks and crevices almost always provide living space for some creature, which is trying to defend it.

A very territorial, rather aggressive fish is the Picasso triggerfish. Its name comes from the spines of the dorsal and pelvic fins, which it raises when trying to lock itself in a hideout from predators. Furthermore, they have sharp little teeth and a strong mouth (usually for crushing crustaceans), which they are not hesitant to use if somebody gets within their space or too close to their eggs during nesting season. Another fish, which can peck quite a bit when being harassed, is the Parrot fish. Its sharp beaklike mouth has jaws, which are strong enough to bite corals and rocks while feeding on algae. This scraping/crunching sound can be heard long before spotting them.

Almost every animal is only reacting in its natural way when people “intrude” their space and sometimes even tease, corner or otherwise harass them, on purpose or accidentally. At least some species are relatively safe from careless human behavior (usually due their size) - barracudas and sharks. Reef sharks resting in caves or cruising around are a common sight and don’t consider people as prey. However, I’ve never seen anybody approaching them in a cave and trying to wake them up, so I’m not sure about the reaction here.