Deadliest Creatures You'll Find in the Ocean & Sea

Sea animals and fish are frequently the victims of negative publicity. More often than not, browsing through wildlife documentary channels on television will reveal a disappointing trend. Many of the documentaries have names such as "Killer Squid" and "The Deadliest Octopus." No wonder some new divers are frightened by aquatic life!

Marine animal behavior can appear threatening to divers who do not understand the purpose behind the behavior. Many sea animals look threatening but are completely docile, and some animals that appear friendly can actually be quite aggressive.

Almost all aquatic life injuries to humans are caused by defensive behavior on the part of the animal. As long as you don't try to pull eels out of their holes, poke the lobsters, or attempt to ride the stingrays, you should be just fine. Don't bother the fish and they won't bother you.

Learn about some of the animals that divers commonly fear and to discover which are dangerous and which are not.

1. Moray Eels - Not Dangerous

Moray eels are large, marine eels commonly found sheltering under ledges or inside holes in the reef. New divers may find eels frightening because they have visible sharp teeth and because they hang around with their mouths open as if they are about to bite. This behavior, which may look like an eel is threatening divers, is really just a way for the eel to pump water across its gills to breathe. The only danger from eels is that they have terrible eyesight and may mistake a prodding finger or dangling piece of gear for a fish. Give moray eels space and they pose no threat.

2. Coral - Dangerous If Touched

One of the most common marine life injuries from scuba diving is scraping against coral. A coral head is composed of a hard (sometimes sharp) limestone support covered by thousands of tiny coral animals. A diver who contacts the reef may be cut by the sharp limestone or stung by coral polyps. Depending upon the species of coral, these injuries range from minor scratches to stinging welts. Of course, a diver can avoid coral injuries completely by maintaining good buoyancy and awareness to stay clear of the reef.

Not only is making contact with coral dangerous to divers, but it's also dangerous to coral. Even the gentlest touch of a diver's fin or hand may kill delicate coral polyps. A diver who touches the reef does more damage to the coral than the coral does to him or her.

3. Stingrays - Not Dangerous

A stingray's pointed and sharp stinger may frighten new divers. However, stingrays are anything but aggressive. Common stingray behavior includes the stingray burying itself in the sand for camouflaging and beating the sand with its wings and nose to look for food. Stingrays will occasionally swim calmly beneath divers. This is not threatening behavior but is a sign that the stingray is relaxed and unafraid.

When approached closely by divers, most stingrays either freeze in an attempt to remain ​invisible or flee the area. A stingray will only sting a diver as a last, desperate defense. Never trap, grab, or press on a stingray's back. Allow stingrays space and the opportunity to escape and they pose no threat.

4. Jellyfish - Dangerous but Rare

A jellyfish sting can injure a scuba diver. However, jellyfish stings are rare because these animals do not attack divers. The danger with jellyfish is that they frequently have long transparent tentacles that are difficult to spot, so a diver may accidentally swim into them.

Before diving in a new location, a diver should talk to local divers (and ideally sign up for an orientation dive with a local guide or instructor) to learn about hazards such as jellyfish. Most jellyfish stings can be avoided by wearing a full wetsuit or dive skin to prevent inadvertent contact with the tentacles.

5. Lobsters and Crabs - Not Dangerous

Lobsters and crabs have powerful claws for crushing prey (such as clams) and for defense. Their claws are not for pinching divers. As divers are not the typical lobster/crab prey, a diver need not fear these crustaceans' claws unless he or she is threatening the animal. A diver who does not attempt to extract lobsters or crabs from the reef and instead enjoys observing these colorful creatures from a respectful distance will not be pinched.