Fiddler Crabs are inhabitants of salt marshes, mud flats, and quiet shores. They are invariably found in large congregations and may be located by their numerous burros in the mud and sand. Fiddlers feed by scooping sand into the mouthparts and filtering out organic material. The sand is then deposited back on the surface as a small ball. These balls are readily identifiable near the burrows. They have a special claw with spoon-like tips that help pick up the sand and transfer it to the mouth. The males of fiddler crabs are known for their single large claw which may be as large as the rest of the animal. This claw is used to attract a mate as well as to intimidate and fight other males. This claw often is brightly colored during the bredding season and the males wave them in characteristic patterns to advertise themselves.

Barnes, R.D., Invertebrate Zoology, 1980, Saunders College and Holt, Rinehart and Winston.