From FrugalReef

[edit] Statistics

• Disposition: Extremely Aggressive
• Lifespan: Long lived (Over 20 years)
• Hardiness: Very hardy
• Care Level: Expert
• Also Kown As: Stomatopods, Thumbsplitters
• Reef Safety: Mantis shrimp are powerful predators and depending on the particular species hunting style, will either eat fish or hard shelled creatures such as crabs and snails.

Mantis shrimp are highly evolved creatures with many unique and interesting features that make them captivating pets for those interested in the care and maintenance of marine predators. Their front appendages are their primary weapon. Powerful and fast, these weapons come in two distinct varieties depending on the species of mantis in question.

The first type are the bludgeons. These appendages are shaped like clubs and accelerate at over 10,400g to a speed of 23m/s, and strike their target with the force of a .22 caliber bullet, 1500N. The speed of this strike is so great that it produces a cavitation bubble in the water. When this bubble collapses, the resulting shock wave will strike the pray a second time. Even if the mantis misses, the shock wave from the collapse of the cavitation bubble will stun the fleeing prey. Mantis shrimp armed with bludgeons prefer to attack and consume hard shelled animals such as snails, crabs, molluscs and rock oysters, but they will also use their weapons to burrow through solid rock and have been known to shatter aquarium glass.

The second type of mantis are the spearers. These mantis posses the same abilities of their "smasher" brethren, but their hunting appendages are shaped like spears instead of clubs. They use these weapons to hunt soft bodied animals such as fish.

In addition to their powerful hunting abilities, mantis shrimp have the most powerful eyes in the animal kingdom. Each eye is fully independent, and can move at a high rate of speed along any axis. These ayes are actually broken down into three distinct parts, giving each eye independent trinocular vision and depth perception. The mantis can perceive all wavelengths of light from ultraviolet to infrared, and are the only animal in the world known to be able to perceive circular polarized light.

Mantis shrimp are assumed to use their powerful visual perception abilities both to identify and range their prey, and to communicate with each other. Some mantis have the ability to use fluorescence to communicate, and others have been shown to produce mating displays using pigments that reflect circular polarized light, making them the only creatures in the world that can perceive them.

[edit] Housing

Mantis shrimp are burrow dwellers and prefer to dig their burrows in the substrate. Sometimes they will live in existing holes in rocks or even snail shells, but usually it is best to provide them with a suitable burrow. If allowed to dig their own, the mantis with clubs will burrow through any rocks that get in their way, and could even burrow through the walls of the aquarium!

To minimize this possibility, it is preferred to use acrylic as opposed to glass aquariums to house these mantis, and to provide a burrow using a U shaped section of PVC pipe buried upright in the sand. The sand should be at least as deep as the mantis is long, and the PVC pipe should be about 1.5x the width of the mantis and as tall as the mantis is long. It should be buried upright in the sand with both holes at the surface.

Mantis are nocturnal hunters and the tank lights shouldn't be strong, as some species are sensitive to high levels of light. Fluorescent or power compact is fine, metal halide is not recommended, but some species that live in shallow areas can tolerate it.

[edit] Feeding

Smashers prefer to eat snails and crabs. Spearers eat fish. Both types can be trained to supplement their diet with frozen food such as shrimp or squid with some difficulty. Feeding is suggested 2-7 times a week. Even if you do choose to supplement with frozen food, live food should still be offered regularly, especially for "smashers", who's hunting appendages are required to be used regularly to keep them healthy and allow them to molt properly.

For training onto frozen food, the mantis can go without eating for up to two weeks, during which a piece of thawed food can be presented to the mantis at the end of a feeding stick once each day until the mantis takes the food item. Letting the mantis go hungry for longer than two weeks is not recommended.

[edit] Catching

If a mantis finds it's way into a reef aquarium not designed to house it, it can be a serious pest. Often brought in as a hitchhiker on live rock, it will hunt with great effect and be very difficult to catch. The best way to deal with these creatures is by careful observation. They prefer to hunt after lights out, and will do so near their burrow. You must determine where they live. If they live in a rock, wait until they return to their burrow, put on some heavy gloves and remove the rock from the aquarium. Place the rock in a bucket of saltwater and spray freshwater into the burrow with a turkey baster to flush them out. Do so carefully and you should be able to sell the creature to your local pet store, as they are valued as pets by many people.

[edit] Danger to People

Mantis shrimp are often called "thumbsplitters". They can deliver painful damage to the hands and are often described as being able to "cut like a razor blade". It's recommended that you keep your hands away from them, and if feeding frozen food, always feed them with a pointed stick or mechanical claw.