Atlantic Spadefish (Chaetodipterus Faber)

Documented life stages: Egg, larvae, juvenile, and adult stages

Size: Up to 36 inches (91 cm)

Color: White with black vertical bands; juveniles are dark black

Coastal distribution: Massachusetts to Brazil Natural habitat: Offshore, estuaries, coral reefs, shipwrecks, channels, vegetation beds, wharves, jetties, inlets, and rocky areas

Local range: Lower Chesapeake Bay; summer and fall

Availability: Occasional to common

Natural salinity range: Above 12 ppt

Salinity zone preference: Mesohaline and polyhaline

Natural diet: Sponges, algae, gorgonians, polychaetes, tunicates, cnidarians, mollusks, crustaceans, and zoanthurians

Aquarium diet: Flake food, live and frozen zooplankton, and chopped seafood

Juvenile aquarium: 20 gallons (76 liters); mild currents; open, rocky habitat; 30–35 ppt salinity; 70–80 °F (21–27 °C)

Aquarium adaptation: Fair to good; disease problems

Compatibility: Good

Biology: The spadefish appears in its northern range beginning in the spring. Its schooling and solitary movements are both described as sluggish and are usually confined to a general area. Offshore and estuarine spawning occurs during the spring and summer. The spadefish utilizes the Chesapeake Bay ecosystem for spawning and nursery purposes. Spawning season runs from May through September on the inner shelf off the coast of the United States. One account of spawning activity noted that it consisted of schools near the water surface with pairs engaged in mouth pushing. A male would follow a female to the surface where they would swim along the surface with dorsal fins exposed and the male parallel or slightly behind the female. The pair would vibrate vigorously during the spawning act. A ripe female is capable of producing up to one million pelagic eggs. The eggs are small and buoyant, hatching after approximately 24 hours. The newly hatched larvae feed on a yolk sac for the first two days of life, after which they begin to actively feed. Approximately 28 hours after hatching, the pectoral rays are well developed and the caudal rays are present. The young migrate to the inshore waters to occupy channels and vegetation beds to continue development before returning to the offshore environment. The young have odd swimming habits that allow them to sway or lean sideways while moving or remaining in a stationary position. This behavior, combined with their darkened coloration, provides protection from predators because they can blend in floating detritus or vegetation commonly found in coastal waters. Along calm beaches, they allow themselves to be tossed or carried by wave action. Offshore migrations occur during the winter. Their life span ranges up to eight years.

Remarks: Juveniles are occasionally available through the tropical aquarium fish market. They are commonly seen in public and home aquariums. Seining, trawling, minnow traps, and baited hooks are the best collection methods for live juvenile specimens. The collection of juvenile species requires keen observations as their body color will be camouflaged against vegetation backgrounds, giving the appearance of dead leaves, when landed in seine nets or when observed in shallow surface waters. Scuba diving in the presence of spadefishes indicates they are docile and approachable. They will often circle divers and can sometimes be coaxed into being hand-fed. Spadefish schools are a pleasing, slow-moving sight to observe. They are a sport fisheries resource.