«Cortney L. ohs r. Leroy CresweLL MAtthew A. DiMAggio University of Florida/iFAs Indian River Research and Education Center 2199 South Rock Road Fort ...»
A guide to
marine baitfish and
their potential for
A guide to
marine baitfish and
Cortney L. ohs
r. Leroy CresweLL
MAtthew A. DiMAggio
University of Florida/iFAs
Indian River Research and Education Center 2199 South Rock Road Fort Pierce, Florida 34945 sgeB 69 February 2013
Despite Florida’s status as a premier fishing location, only two of the 257 baitfish farms recorded in the 2005 USDA Census of Aquaculture were located in Florida. Since 2005 about 10 new marine baitfish farms have been added, but this disparity clearly illustrates the potential for expansion and diversification of aquaculture within Florida to include marine baitfish production.
Today almost all marine baitfishes sold in stores are wild caught using nets and traps, making availability of most species seasonal despite a year-round demand. Marine baitfish produced by aquaculture could provide anglers with a consistent supply of sought-after species in desired sizes regardless of season, as well as potentially alleviate collection pressure on targeted wild populations.
Successful production and marketing of marine baitfish will require a business plan that includes production of multiple crops through controlled spawning during the off-cycle. A year-round supply would allow marketing of cultured baitfish when the wild supply is limited so that a premium price can be attained.
Substantial research to evaluate the aquaculture potential of many species of marine baitfish suggests that some species have high aquaculture potential while others, for a variety of reasons, are less promising. You can learn more by reading the research and extension publications referenced at the end of this document, and by visiting the University of Florida/IFAS Indian River Research
and Education Center’s aquaculture website:
Croaker are medium-sized, slightly elongate, moderately compressed, and silvery in color with a pinkish cast. The back and upper sides are grayish with black spots forming irregular, oblique lines above the lateral line. The dorsal fin has small black dots and a black edge; other fins are pale to yellowish. The chin has three to five pairs of barbels along the inner edge of the lower jaw. Atlantic croaker “croak” by vibrating their swim bladders with special muscles as part of their spawning ritual and when handled.
Range: The Atlantic croaker occurs in the northern and eastern parts of the Gulf of Mexico, along the Atlantic coast of the United States from south Massachusetts to Florida, in the Greater Antilles, and along the South American Atlantic coast from Surinam to Argentina. Its US fishing grounds extend from the Rio Grande to Tampa Bay in the Gulf of Mexico and from northern Florida to Cape Hatteras on the Atlantic coast. In Florida, Atlantic croaker are seldom found south of Tampa Bay in the Gulf of Mexico or the Indian River Lagoon on the Atlantic coast.
Habitat: Croaker are found over mud and sandy bottoms in coastal waters to about 3,300 feet (1,000 m) deep and in estuaries where their nursery and feeding grounds are located. Croaker can thrive in fresh water or sea water and in a wide range of temperatures 48–90°F (9–32°C); they are most abundant in waters over 75°F (24°C). Post-larval and juvenile Atlantic croaker occupy estuarine nursery areas where they feed on benthic plankton and invertebrates, such as grass shrimp and worms.
Size: Average 8 inches (20 cm), maximum 14 inches (36 cm) Bait use: Small croaker (2–3 inches, 5–7.5 cm) are used for flounder and spotted sea trout, with medium sizes (4–6 inches, 10–15 cm) appealing to redfish, snook, and piscivorous gamefish. Larger specimens (7–8 inches, 17.5–20 cm) are used offshore for grouper and snapper.
2 Aquaculture potential: Although the reproductive biology and spawning of wild-caught fish is well-documented, aquaculture methods for croaker are only partially known. Spawning occurs offshore in late summer, although they have been induced to spawn with hormones; females release 40,000–110,000 eggs.
Larval rearing regimes similar to red drum have been used with relatively good success. Newly hatched larvae can be cultured in tanks with phytoplankton and fed rotifers (Brachionus spp.) 3 to 12 days post hatch. Brine shrimp (Artemia sp.) can be added during days 10 to 12, as well as micro-particulate diets (250 µm particle size). Juveniles consume high protein (45%) formulated diets and exhibit rapid growth and survival. Wild juveniles grow rapidly, reaching 6–8 inches (15–20 cm) in the first year. Wild caught juveniles reared in cages in heated effluent (86°F, 30°C) and fed 45% protein formulated feed grew 0.6 inches (1.5 cm)/month. At that growth rate, a 1-inch (2.5 cm) croaker would reach 4 inches (10 cm) total length in 5 months.
Suggested reading Creswell, R.L., C.L. Ohs, and C. L. Miller. 2010. Candidate Species for Aquaculture: Croaker, Micropogonias undulatus. University of Florida, www.edis.ifas.ufl.edu/fa148.
Pinfish are compressed and oval, olive colored above, bluish-silver along the sides with thin yellow stripes running longitudinally. A dark shoulder spot occurs near the anterior origin of the lateral line. Six broad diffuse vertical dark bars occur along each side of the body, and these are most prominent in younger individuals and in individuals experiencing stress. The anal fin and the forked caudal fin are both yellowish with broad light blue margins.
Range: Pinfish inhabit the eastern coast of the United States from New England south to Florida (most abundant south of Virginia), Bermuda, the northern Gulf of Mexico, the northern coast of Cuba, and the Yucatán Peninsula. They are absent from the Bahamas and Antilles.
Habitat: Pinfish are found throughout estuaries and nearshore waters, typically in vegetated benthic habitats such as seagrass beds. The species is also commonly encountered on bare sand or rock reefs, mangrove habitats, and off of inlet jetties. Juveniles inhabit vegetated shallow estuaries and mangroves. Adults inhabit vegetated deeper channels, jetties, and offshore reefs. Pinfish tolerate water temperatures ranging from 50–95°F (10–35°C) and salinities 0–75 g/L.
Size: Average 3–5 inches (8–10 cm), maximum 12 inches (30 cm) Bait use: Popular bait for offshore bottom fishing. Pinfish ranging from 1.5–6.0 inches (3.75–15 cm) are frequently used by both inshore and offshore anglers to target a wide range of game fish. Arguably the most popular live bait in the southeastern US.
Aquaculture potential: Pinfish are a resilient, easy-to-maintain, fast-growing fish that tolerate a wide range of environmental conditions, and as such show great potential as a new aquaculture species with the purpose of being sold as marine baitfish. They tolerate high densities, reproduce in tanks, grow rapidly, and have established high-demand markets. Hormone injections are effective for ovulation and volitional spawning in pinfish; up to 90,000 eggs per female have been collected. Fertilized pinfish eggs have a single oil globule, a spherical yolk, and are buoyant in seawater. Eggs range in diameter from 0.90–1.05 mm. Pinfish larvae should be cultured at approximately 77°F (25°C) and fed rotifers, Branchionus sp., at first feeding (3 days post hatch) because they are small enough to be consumed. Rotifers should be fed to larvae at a density of 5–15 rotifers/mL from 3 to 21 days post hatch. Early juveniles have fully formed fins and range in size from 0.47–0.55 inches (12.0–13.9 mm). Pinfish grow rapidly and can reach a marketable size of 1.97–4.9 inches (5.0–12.5 cm) midway through their first year. Pinfish can grow 0.35–0.39 g/day with a mean survival of 94 to 99% over an 82 day growth period. Average food conversion ratio ranges from 1.7 to 1.9. Further studies in recirculating aquaculture systems, inland ponds, and low-salinity culture methods are needed to define the most appropriate culture techniques and protocols.
Suggested reading Ohs, C.L., M.A. DiMaggio, and S.W. Grabe. 2011. Species Profile: Pinfish, Lagodon rhomboides.
Southern Regional Aquaculture Center Publication Number 7210. 6 pp.
Ohs, C.L., S.W. Grabe, and M.A. DiMaggio. 2010. Candidate Species for Aquaculture: Pinfish, Lagodon rhomboides. University of Florida, www.edis.ifas.ufl.edu/fa168.
Killifish are stout-bodied, about one-fourth as deep as long. Their body is thickest just posterior of the pectoral fins. Both back and belly are rounded, and the top of the head is flat between the eyes and the snout. The mouth is at the tip of the snout and is so small that it does not gape back to the eye. The most striking feature of Fundulus is their very deep caudal peduncle and rounded caudal fin. Killifishes vary in shade from very pale to dark, according to the color of their surroundings. Out of breeding season the males are dark greenish or steel blue above, while the belly is white, pale yellow, or orange. The dorsal, anal, and caudal fins are dark green or dusky with pale mottling. The females are typically paler than the males and are more uniform in color.
Range: F. grandis—Florida to Vera Cruz, Mexico; F. heteroclitus—Gulf of St.
Lawrence to NE Florida; F. seminolis—throughout Florida, mostly inland areas.
Habitat: Fundulus spp. are recognized as hardy fish that tolerate a wide range of water temperatures and salinities. Found in shoals along sheltered shores where the tide flows over seagrass, tidal creeks that cut through salt marshes, on the shores of harbors, and in the brackish water at the mouths of streams and estuaries, particularly in little muddy pools, creeks, and ditches. As a group, they are very tolerant of low dissolved oxygen. Killifish are omnivorous, feeding on vegetation, plankton, and small crustaceans and mollusks, and occasionally eggs and small fish.
Size: Average 3 inches (8 cm), maximum 8 inches (20 cm) Bait use: These hardy fish are one of the most popular bait species for both marine and freshwater fishing. They are particularly popular as flounder bait.
Aquaculture potential: Considerable information is available on the technical aspects of Fundulus sp. culture. In addition, few perceived regulatory concerns or environmental impacts should limit continued development. However, economic issues appear to be a major impediment to commercial expansion.
Fundulus species are oviparous; fecundity is relatively low at 100 to 300 eggs per day over a 3 to 5 day spawning period for F. heteroclitus, depending on fish size, and lower with other Fundulus species. The timing and duration of the spawning seasons for the different species will vary based upon geographic location and water temperature parameters. Multiple spawns can be expected over the course of a spawning season. Eggs are attached to solid substrates for the incubation period of 7 to 21 days depending upon water temperature and salinity. A need exists for research on Fundulus culture in ponds and recirculating water systems, and egg incubation techniques.
Suggested reading Adams, C. and A. Lazur. 2001. Economic considerations for the prospective mudminnow culturist in Florida. University of Florida, www.edis.ifas.ufl.edu/fa309.
Anderson, J.A. and C.C. Green. 2013. Cacahoe minnow production manual. http://www.lsuagcenter.com/ en/crops_livestock/aquaculture/baitfish/minnows/Cocahoe-Minnow-Production-.htm.
DiMaggio, M.A., C.L. Ohs, S.W. Grabe, B.D. Petty, and A.L. Rhyne. 2010. Osmoregulatory evaluation of the Seminole killifish after gradual seawater acclimation. North American Journal of Aquaculture.
Pigfish have long anal fins, matching the soft dorsal fin in shape and in size.
The head is sloped and pointed, the snout almost pig-like, and the lips thin. A background color of bluish-gray is marked with brassy spots in indistinct lines that are horizontal below the lateral line but extend obliquely upward and backward above the lateral line. These oblique markings are also found on the cheeks. The head is covered with bronze spots, and the fins are yellowish bronze with dusky margins. The name pigfish was probably derived from the chattering noises they make when caught. Like other members of the grunt family, a pigfish makes a grunting sound by rubbing the teeth in their throat together. Pigfish also use these pharyngeal teeth to grind up shellfish and small bits of other food.
Range: Pigfish inhabit the Atlantic coast of the United States from New York to the northern Bahamas and Bermuda, but are less common north of Virginia.
They are also found in the Gulf of Mexico from Florida to the Yucatán peninsula.