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Fiddler Crab

Jan 18, 2005
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Greece and USA (dual citizenship)
Common Name(s) Fiddler crab, Calling Crab, Deaf Ear Crab, Fever Crab, and many others.
Scientific Name: Uca Pugnax
Family: Ocypodoidea
Origin: Not completly clear, but most likely Florida marsh lands. (United States)
Maximum Size: Up to 2 inches.
Care: Brackish water (1.005-1.010 specific gravity), ideal tempature between 75-81 degrees. CAN NOT LIVE IN A COMPLETE WATER FILLED AQUARIUM. This crab is semi terrestial, meaning it lives on both land and water. To acheive this, a covered mangrove tank is ideal. Sand is the only subtrate suitable. Sand is ideally about 7 inches deep but can be put with about 2.5 inches. Minimum of ten gallon tank. There should be roots, wood, rocks, mangrove plants, caves and many other hiding and climbing places. Some sand should be above water's surface.
Feeding: This crab is a scavenger and will eat just about anything but the ideal diet should include ocean plankton, hermit crab food, algae disks, shrimp pellets, crab pellets, and occasionally catfish wafers. Note that the food should not be placed in the water, but in a shallow contanier small enough for the crabs to get in and out easily.
Sexing and Breeding: Males have one huge claw (almost as big as themselves) while females have 2 small claws. Breeding may occur in the males sand burrows, but it is impossible to take care of the hatched eggs as they spend their first part of thier lives as plankton.
Comments:Not a tropical fish but are commonly sold in many lfs and many people in the hobby own them so I decided to make a profile on them. Awesome creature and habitat to have. The most common question about them is can i keep other fish in the mangrove tank with them? In short no, but many cases have been found succesful, so look it up and test it out. Another common question is: how many can I house in my mangrove tank? This is difficult to answer as every situation is different. My guideline is 4 females to 1 male and about 1 crab per 3 gallons of tank. This is my own guideline that Ive found to be succesful, but like i said every situation is different. Be careful when netting them for any reason, as they are very fast and will scurry out of the net before you can blink. More active at night time, but highly active during the day. Life expectancy is about 2 and a half years. Is commonly abused as people dont know how to care for them, Ive even seen them in bowls! If you plan on buying some check this page and many others sources of information to properly care for them.


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