Pistol Shrimp

Pistol Shrimps are tiny creatures with a deadly weapon. They are capable of shooting supersonic blasts from their fingertips with enough force to instantly stun or kill their prey.



You may notice that one claw of a pistol shrimp is much larger than the other, and very strangely shaped. This claw serves as both its lethal weapon, and its voice. This claw can be forcefully snapped shut, shooting a jet of water out at such a high speed that it actually vaporizes the water. This causes a small air bubble to form. The bubble collapses with enough force to send concussive shockwaves capable of stunning and incapacitating prey.

A pistol shrimp will lie in wait under a rock or in a burrow until food comes along. When it is in range, the shrimp will forcefully snap its oversize claw shut, shooting out sonic waves that incapacitate its prey. The helpless victim is dragged unconscious into the burrow and eaten by the pistol shrimp.

Another unusual thing about pistol shrimps is that they often allow a fish to live with them. Certain kinds of goby fish often share burrows with pistol shrimp. The fish serves as a guard dog, protecting the shrimp from bigger predators. In return, the pistol shrimp works hard to keep the burrow clean and excavate their home.

The loud blast created by a pistol shrimp's claw can be heard from great distances. Because of this, they also use their claw for communicating with other pistol shrimps. When you listen underwater you may hear a lot of popping sounds. Some of them may be made by pistol shrimps firing off their sound waves to communicate with each other.

Crabs

Crabs are Crustaceans and members of the Arthropod phylum. They have a hard exoskeleton surrounding their entire bodies which acts as a suit of armor. Most crabs use their powerful claws to fend off attacks and capture prey.

Some species such as the hermit crab scoot into empty snail shells and carry the shell on their backs. When threatened, they can disappear into the shell.

Other species rely on camouflage to hide from predators.

Most species of crabs can survive for short periods of time outside the water. Their shells hold enough water to keep their gills moist, therefore allowing them to breathe on land. Some crabs spend most of their lives on land.

Crabs range in size from barely visible to the giant coconut crab pictured here. Crabs can be found all over the world in a staggering variety of shapes and colors.

Zooplankton

Just about any sample of seawater taken will be full of plankton. Plankton is made up of microscopic plants (phytoplankton) and animals (zooplankton). Zooplankton are mostly too small to be seen with the naked eye. They are made up of the larva of some sea creatures, and other adult animals that never grow above microscopic sizes. Zooplankton are the second step in most food chains. Zooplankton eat phytoplankton, and often other zooplankton as well. They are in turn eaten by very small animals.

Some zooplankton swim while others simply drift. Some examples of the kinds of animals that can be found in zooplankton are krill (the tiny shrimp eaten blue whales), tiny jellyfish, and crab larvae. Many of the ocean's animals spend at least part of their lives drifting through the soup of plankton.