To help the public gain a deeper understanding about crab species and to promote conservation of their natural habitat, Chunghwa Post is issuing  a set of four stamps featuring fiddler crabs, which live in estuary mud flats, entitled Taiwanese Crabs Postage Stmaps (Issue of 2004.)   Fiddler crabs are representative of the crabs inhabiting tropical and subtropical seashore mud flats. Currently, around 80 species have been identified globally, among which 10 are found in Taiwan. Fiddler crabs are representative of the crabs inhabiting tropical and subtropical seashore mud flats. Currently, around 80 species have been identified globally, among which 10 are found in Taiwan. Fiddler crabs have slender matchstick-like eyestalks attached to their eyes. Male fiddlers have one claw that is much larger than the other. These claws look like pairs of large scissors and increase in size with the size of their bodies. Female fiddlers, on the other hand, have equal-sized small claws. Most fiddler crabs are brilliant in color and live in groups of single-crab burrows that they excavate in tidal mud flats in estuaries and mangrove forests. They only come out of their burrows to forage for food, mate or mend their burrows when the tide is out.   The designs of the stamps follow:   (1)         Formosan Fiddler Crab (Uca formosensis) (NT$3.50)—Burrow Construction: Largely dark brown in color, the male Formosan Fiddler Crab’s enlarged fiddler claw resembles a pair of white scissors. It is the only endemic species in Taiwan. The chimney-like constructions it builds around the entrances of its burrows are mostly over 10 centimeters in high, and some even reach over 20 centimeters. (2)         Yellow-clawed Fiddler Crab (Uca borealis) (NT$3.50) —Male Combat: Over 90% of the males are right “clawed.” The males often fight over their territories or females. During these fierce battles, both crabs will pinch each other with their fiddles, and sometimes one of them will even throw the other into the air. (3)          Orange-clawed Fiddler Crab (Uca arcuata) (NT$5)—Plugging up the Burrow: Orange-clawed Fiddler Crab is nicknamed the “net pattern fiddler” in Chinese because it has a net pattern on its shell. It is one of the most common fiddler crabs in Taiwan. When it finishes its outside activities, or when the tide is coming in, it will roll up a small amount of mud to plug up the opening of its burrow. (4)         White Fiddler Crab (Uca lacteal) (NT$25)—Foraging in Mud Flats: When frightened, its coloration will rapidly change from pure white to dark gray. White Fiddler Crab feeds on organic matter in mud or sand. It uses its smaller claw to scoop up mud or sand and then pass it to its mouth. After the nutrients are removed, it then redeposits onto the ground the non-edible matter, which is usually mistaken for feces.