Fish Facts » Spadefish
The Atlantic spadefish is a deep-bodied, compressed disk-shaped fish with a blunt snout. The mouth is small with the maxilla extending below the nostrils in adult individuals. The head and fins are scaled and the opercle terminates in an obtuse point above the origin of the pectoral fins. The first and second dorsal fins are separated; the anterior rays of the second dorsal fin as well as the anal fin are elongated. The margin of the caudal fin is concave. This fish is silvery in color with 4-6 black vertical bands on each side of the body. These bands sometimes fade or become obscure in larger fish. The first band runs through the eye and the last band runs through the caudal peduncle. Juveniles are dark brown to black with some lighter mottling and appear similar to dark leaves in the water. The adult coloration is similar to that of the sheepshead (Archosargus probatocephalus), however the Atlantic spadefish has a shorter snout, rounder overall body shape and larger soft dorsal and anal fins than the sheepshead. Also, the black vertical bands on the sheepshead do not fade to the extent they do on the spadefish.
This schooling fish is abundant within the shallow marine and brackish waters of mangroves, beaches, harbors, and shipwrecks. It is found at depths of 3-35 m. Juvenile Atlantic spadefish reside in very shallow water, often swimming at an angle, disguising themselves as dead leaves or mangrove pods to avoid predation. Adults often school in groups of up to 500 individuals.
Benthic invertebrates including crustaceans, mollusks, annelids, sponges, and cnidarians are preyed upon by the bottom feeding Atlantic spadefish. This fish may also feed occasionally on plankton as well as nibble on jellyfish tentacles. Feeding occurs throughout the day with a peak around midday.
The Atlantic spadefish is of only minor commercial value. However, it is valued by recreational fishers due to its size and tenaciousness. The flesh of this fish is considered relatively good although they have been associated with ciguatera poisoning. Atlantic spadefish are often residents of large public aquarium facilites and they have been successfully reared in captivity. In their natural habitat, Atlantic spadefish often swim circles around scuba divers.
The Atlantic spadefish reaches a maximum total length of 35.8 inches (91.0 cm) and a maximum reported weight of 19.8 pounds (9 kg). Both sexes are mature at approximately one year of age.
The Atlantic spadefish is the only member of the family Ephippidae to reside in the western Atlantic Ocean. It is limited in range to the Atlantic Ocean from Massachusetts (US) south to southeastern Brazil, including the northern Gulf of Mexico. It is also found off Bermuda and throughout the Caribbean.
Florida Museum of Natural History
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