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Crabs Video of Giant Hermit Crab - Click here
The hermit crab is a type of crab that doesn't have a very hard shell. Not a true crab, it uses other animals' old shells for protection; they especially like old whelk shells. As the hermit crab grows in size, it must find a larger shell. The hermit crab is a crustacean; there are about 500 different species of hermit crabs around the world. Most hermit crab species live on the ocean floor, but many live on land. Female terrestrial (land based) hermit crabs must return to the sea to breed. Hermit crabs are invertebrates, animals without a backbone. They have an exoskeleton, an outer shell that provides support for their body but does not provide much protection from predators. They vary widely in colour, from red to brown to purple, with stripes, dots, and other patterns. They have ten jointed legs; the front two legs have large, grasping claws (called pincers or chelipeds) and the rear pair of legs are very small. They have a flattened body, sensory antennae, two eyes located at the ends of stalks, and a soft, twisted abdomen (which the hermit crab keeps hidden inside its shell). Diet: Hermit crabs are omnivores (eating plants and animals) and scavengers (eating dead animals that they find). They eat worms, plankton, and organic debris.
Sesarma Bidens The Red Claw Crab gets their name from their bright red claws. These crabs are usually sold as freshwater crabs. Crabs are obviously not of internet material, sad to say, there is so little online. The Red Claw Crabs eat about anything that settles to the bottom on the tank. Java Moss, Corkscrew Vallisneria, Duckweed, and Brazilian Waterweed are eagerly eaten by these crabs, but only in small amounts. They will also eat peas and snails. Crabs are crustaceans, as they grow they will moult. This is where the crab sheds its old exoskeleton, or shell. The crab will be vulnerable after his moult till his new shell hardens. Moulting is a very stressful period for crabs, and they might die under the stress. Crabs need access to air, driftwood rising above the water level is a good idea. But make sure that there is no exit route from the aquarium for the crab, Harry Houdini could well be a pseudonym! (He was an escapologist of supreme achievements) If there is room permitting, ensure that there is a suitable hiding place for the crab to retreat to when he wishes. Care Level: Moderate The size of the claws makes it very easy to tell the difference between male and female fiddler crabs. A male fiddler crab has one claw that is very large compared both to its other claw and the claws of the females. The females have two small claws.
The group of crabs known as fiddler crabs actually encompasses over 90 species and subspecies of the genus Uca that come from a variety of locations. The fiddler crabs found in pet stores are most likely semi-terrestrial brackish crabs, which means they need some salt in their water as well as access to air and dry land. Because most of these crabs are naturally from brackish waters, most experts recommend putting salt (get aquarium salt from the pet store; never use table salt) in the water. The ideal amount of salt to add is controversial, but it is probably best to get a hydrometer and add enough salt to the water to attain a specific gravity of around 1.005 - 1.010. Hydrometers are not all that expensive and can be found at pet stores and also home brewing shops. Alternatively, your package of aquarium salt may have instructions for producing brackish water conditions. It is okay to vary the salt concentration/specific gravity slightly as these crabs would naturally experience some variations in salinity. Temperature Fiddler Crabs Need Land
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Feeding Fiddler Crabs
Signs of health in fiddler crabs include growth and regular molting. Once a crab molts, their previous exoskeleton will likely be whole in the tank, looking eerily like a ghost. It is a good idea to leave the exoskeleton in the tank, at least for a week or so. Often the crabs will ingest part of the shed exoskeleton, and it serves as an excellent source of calcium (which they need to produce their new exoskeletons). Claws and legs may be lost but will regenerate over a couple of molts. Fiddler crabs may produce eggs in captivity (the female carries eggs on her belly), but successful rearing of the young in the aquarium is next to impossible due to the way their natural live cycle works (the larvae grow in deeper ocean waters and return to shore at maturity). All images were from store stock.
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