TAXONOMY

NAME - Bluefish
OTHER COMMON NAMES - blue, tailor, elf, fatback, snapper, snap mackerel, skipjack, skip mackerel, horse mackerel, greenfish and chopper

Table of Contents:
COMMENTS ON TAXONOMY
STATUS
COMMENTS ON STATUS
COMMENTS ON ADULT FOOD
Food and Feeding
COMMENTS ON ENVIRONMENTAL ASSOCIATIONS
COMMENTS ON FEEDING JUVENILE ENVIRONMENTAL ASSOC
LIFE HISTORY 
Morphology/Identification
Reproductive Features
Migration
COMMENTS ON MANAGEMENT PRACTICES

COMMENTS ON TAXONOMY -
The bluefish is the only living species in the family Pomatomidae, whose closest relatives are the jacks and pompanos, family Carangidae. Several geographical races of P. saltatrix are recognized (Lund 1961).

STATUS
Coded Status: Sport Fish, Game (Consumptive Recreational), Commercial, Commercial/consumption, Migrant

COMMENTS ON STATUS -
Bluefish are a migratory, pelagic species. Bluefish comprise less than 1% of the U.S. Atlantic coast commercial fish ery landings, in terms of both weight and dollar value; but the commercial catch has tripled over the past two decades (Wild 1977; Thompson 1986), and recent trends in U.S. fish consumption indicate economic incentives for much greater catches: Per capita consumption of edible fish and shellfish in the United States during 1985 was 20% greater than during 1975, and 50% greater than during 1965. "Nutritional demands of consumers, as well as improving methods of catching, handling, and processing seafood may reasonably be expected to lead to greater consumption levels in future years" (Thompson 1986). In contrast to its commercial importance, the recreational value of this species is enormous. Bluefish comprise about 15% by numbers and nearly twice as much by weight of Atlantic coast sport fish landings. About 90% of the average 55 million kg of bluefish taken annually over the past 7 years (about 8 times more than the commercial catch) were hooked by anglers in the mid-Atlantic region (Holliday 1984, 1985a, 1985b, 1986). Because bluefish are abundant along most of the east coast, easy to catch, good to eat, and provide an unusually long fishing season, they have remained popular with sport fishermen since the 1800's. "No other species is as important to all sorts of anglers... It is unlikely that any other species could completely replace it, were it to disappear" (Wilk 1977). A bluefish Fishery Management Plan was completed in 1984 by the Mid-Atlantic Fishery Management Council in cooperation with the NMFS, New England and South Atlantic Fishery Management Councils, and the Atlantic States Marine Fisheries Commission. However, the plan was rejected by the Secretary of Commerce. Although the Plan was rejected, bluefish remained a major value to the nation and public concerns about bluefish overexploitation were not abated. Subsequently, the Fishery Management Councils and the ASMFC agreed  to proceed jointly on the development of a new bluefish management plan containing compatible management measures that could be enacted in both state and federal waters. The draft plan is dated September 1988.

COMMENTS ON ADULT FOOD -

Food and Feeding
Bluefish are voracious predators throughout their lives, relying primarily on vision to detect prey, although their olfactory sense is also well-developed (Olla et al. 1970; Wilk 1977). Food habits of larvae and early juveniles have not been well studied, but they presumably select various zooplankton, including larvae of other pelagic-spawning fishes (Norcross et al. 1974; Kendall and Walford 1979). Young-of-the-year arriving in the coastal nursery areas feed on small shrimp, anchovies, killifish, silversides, and many other available prey; those remaining at sea probably find small pelagic fishes and crustaceans as forage. As their size increases, so does the list of potential prey. A wide variety of fish and invertebrates have been recovered from bluefish stomachs, including such unlikely items as the sand dollar (Echinarachnius parma), the sea lamprey (Petromyzon marinus), various sharks and rays, and the northern puffer (Sphoeroides maculatus). More typical fare of adults includes the common squid (Loligo peali), various shrimp and crabs, alewives (Alosa pseudoharengus), and other shad and herrings, Atlantic menhaden (Brevoortia  tyrannus), silver hake (Merluccius bilinearis), pinfish (Lagodon rhomboides), spot (Leiostomus xanthurus), butterfish (Peprilus triacanthus), smaller bluefish, and many other species (Wilk 1977; Richards 1976).

Lassiter (1962) noted the elimination of invertebrates from the diet as bluefish increase in size. Among young adults the stomach contents typically include 10% to 20% invertebrates by volume, but larger fish are almost exclusively piscivorous. Young fish also chop their food into smaller pieces, making diet analysis more difficult; large adults typically swallow their prey whole. Feeding activity peaks in early morning and continues throughout daylight hours (Lund and Maltezos 1970). In studies of captive bluefish, the normally close-knit school breaks up during feeding as individuals break away to chase particular prey. The fish regroup a few minutes after the  prey have been consumed. Fish satiated on small prey resume feeding when larger prey of the same species are offered, suggesting that feeding motivation is influenced by prey size (Olla et al. 1970).

 COMMENTS ON ENVIRONMENTAL ASSOCIATIONS -
Temperature:
Temperature is probably the single most important environmental parameter determining bluefish distribution, migration, feeding, spawning, and recruitment success (Lund and Maltezos 1970). The 18 to 22 degree C temperature range for minimum cruising speed corresponds well with the majority of commercial and recreational bluefish catches, and also with conditions in the mid-Atlantic bight where summer spawning occurs (Norcross et al. 1974). The south Atlantic waters between the continental shelf and the Gulf Stream where spring spawning occurs, average slightly higher, 20 to 26 degrees C.
Salinity:
Juvenile and adult bluefish are moderately euryhaline, occasionally ascending well into estuaries where salinities may be less than 10 ppt. Eggs and larvae are probably less adaptable: salanities have been reported between 35 and 38 ppt in the south Atlantic continental slope waters where the spring spawners originate, and 30 to 32 in the mid-Atlantic summer spawning waters. Whether salinity gradients can act as barriers to migration, as thermal gradients can, has not been determined.
Oxygen:
Pelagic open-ocean fishes are usually not well adapted for low oxygen conditions. Situations where bluefish have avoided areas of low dissolved oxygen have been reported.

COMMENTS ON FEEDING JUVENILE ENVIRONMENTAL ASSOC -
Juveniles drifting north of Cape Hatteras congregate at the Gulf Stream/continental shelf interface in the mid-Atlantic while shelf waters are still much cooler. As the season advances, the shelf waters warm, and the young bluefish make their voyage across the shelf to the estuaries when shelf temperatures reach 18 to 20 degrees C. These thermal edges apparently serve as important cues to juvenile migration, insuring that the young arrive in suitably warm nursery habitats (Kendall and Walford 1979).

LIFE HISTORY 

Morphology/Identification
The adult bluefish is an oblong, laterally compressed, streamlined fish up to 1 m total length (TL), with a large compressed head, large oblique mouth, belly compressed to a blunt edge, and forked caudal fin. Coloration is bluish to greenish dorsally, fading to silver ventrally; a dark blotch at each pectoral fin base is the only distinct marking. Body, cheeks, and opercles are covered with weakly ctenoid scales, 95 along lateral line, but the top of the head and the ridge above the cheeks are unscaled. The anterior spiny dorsal fin, with 8 to 9 spines, is separate from and lower than the posterior soft dorsal, with 24 to 25 rays. The anal fin, with 2 to 3 very small spines and 26 to 28 rays, is slightly behind and about equal in length to the soft dorsal fin. Pectoral fins are rather low set, and the pelvic fins attach directly beneath them. Maxillae extend to the rear of the eyes, the premaxillae are protractile, and the lower jaw projects forward of the mouth. The jaws each have a row of long, unequal, widely spaced teeth; the vomer, tongue, and palatines have several bands of villiform teeth. Vertebrae number 24 to 26. (Compiled from Jordan and Evermann 1896-1900; Bigelow and   Schroeder 1953; Miller and Jorgenson 1973).

Reproductive Features
Bluefish are heterosexual and reach sexual maturity during their second year at about 35 cm fork length (FL). Males mature slightly earlier than females, but neither growth rate nor ultimate adult size is sexually dimorphic (Wild 1977; Wilk et al. 1978). The sexes cannot be distinguished by external features. Lassiter (1962) reported a 2-to-1 female to male ratio in North Carolina, but Wilk (1977) reported a 1-to-1 sex ratio among schools of all ages along the entire Atlantic coast. Fecundity of 3- to 4-year-old females ranged from 0.6 to 1.4 million eggs in a small sample from North Carolina (Lassiter 1962). Fertilization is external; eggs and sperm are shed into the open sea by migrating schools, without further prenatal care. Larvae drift and feed among the surface plankton until they metamorphose and begin their migrations either south or toward the coastal nursery areas (Kendall and Walford 1979).

Migration:
Fisheries data suggest that most North American bluefish are migratory, spending their summers from New England to Cape Hatteras, N.C., and their winters around Florida and the Gulf Stream. Smaller bluefish generally travel close to shore during both the spring and fall migrations, except during spawning. Older fish travel near shore in their northern range, but apparently shift farther offshore in the south with periodic forays toward the coast, since they appear infrequently but in large schools south of Virginia, especially during the fall migration (Lund and Maltezos 1970; Wilk 1977). There also appear to be small non-migratory (or less migratory) populations in the south Florida and Gulf of Mexico regions (Barger et al. 1978; Kendall and Walford 1979). The degree of reproductive isolation of the various Atlantic and gulf coast populations (including those that are migratory and those that appear to be non-migratory) is unclear. Wilk (1977) and Matlezos (1970), however, recognize very small but consistent morphological differences between the two major spawning aggregations that comprise the mid-Atlantic fishery: a south Atlantic spring-spawning stock and a mid-Atlantic summer-spawning stock. The spring-spawning stock arrive at the continental slope/Gulf Stream interface between north Florida and Cape Hatteras, N.C., mainly in April and May, from their wintering areas in south Florida or offshore in the South Atlantic. Spawning occurs in pulses as the schools travel northward. North of Cape Hatteras the spent adults begin heading toward shore for the remainder of the warm season. Smaller ones generally turn west sooner and find their way into Albemarle Sound, Chesapeake Bay, and Delaware Bay, whereas larger ones follow the continental slope farther north and turn west into Long Island Sound and Narragansett Bay, or continue around Cape Cod to the north Atlantic region. As temperature and photoperiod decline in autumn, the schools orient southward again, young ones close to shore and older ones farther offshore (Wilk 1977; Kendall and Walford 1979). Summer-spawning bluefish arrive over the outer half of the continental shelf (about 50 to 150 km offshore) between Cape Cod and Cape Hatteras from June through August, probably from the same wintering areas as the spring spawners. After spawning, adults migrate toward the mid-Atlantic and north Atlantic coasts, especially Long Island Sound (Lund and Maltezos 1970). They depart in autumn along with the spring spawners.

MANAGEMENT PRACTICES

RESULT MANAGEMENT PRACTICE
Beneficial Regulating harvest - setting age limits
Beneficial Regulating harvest - setting bag/creel limits

 COMMENTS ON MANAGEMENT PRACTICES -
Recreational and commercial fishing regulations for bluefish in the mid-Atlantic exist in several states, but lack of enforcement and inconsistency from state to state limit their effectiveness (Wilk 1977). The objective of states that do regulate the fishery is generally to limit the catch of young-of-the-year bluefish, which is thought to promote successful recruitment into larger, more desirable age classes. The Magnuson Fishery Conservation Management Act of 1976 created a series of regional Fishery Management Councils to develop overall management plans for important species and to coordinate the states' management efforts. The Mid-Atlantic (New York to Virginia) Fishery Management Council completed a proposed Fishery Management Plan for bluefish in 1984 in cooperation with the New England FMC and South Atlantic FMC. The council adopted a provisional maximum sustained yield (MSY) of 95 million kg annually based  upon MSY estimates by Boreman (1983) and NMFS (1983) and upon the evidence for increasing recruitment from their trawl surveys. The plan proposed an allocation of 20% of the total U.S. bluefish catch for commercial fishermen, mostly in the mid-Atlantic region; the remainder would be allocated to recreational fishermen (Mid-Atlantic FMC 1984). But the plan was disapproved by Congress that same year because the bluefish catch in the federally regulated Fishery Conservation Zone (3 to 200 miles) is only a fraction of the catch in nearshore (less than 3 miles) state regulated waters, so Federal regulation was deemed inappropriate (David Keifer, Mid-Atlantic FMC, pers. comm.). Currently, the three Fishery Management councils are working with the Atlantic States Marine Fisheries Commission, a coalition of state agencies, to develop a coast-wide plan to be adopted by all states in lieu of a federal management plan. Periodic disease outbreaks over the past 20 years (Mahoney et al. 1973) suggest that the species is sensitive to coastal water quality degradation, and therefore coastal land use planners and developers should consider the effects of their activities upon bluefish populations. The commercial fishing season from Cape Cod, MA to Delaware Bay is  primarily May through November, with peak catches from July to September. In Maryland and Virginia, bluefish are caught year-round, with peak catches earlier in the summer. In North Carolina, the bluefish fishery is year-round, with peak catches in the winter: small fish are taken in the sounds and nearshore waters from April through December, and recently, great quantities of larger fish have been taken offshore during winter (Wilk 1977;  Mid-Atlantic FMC 1984). Fishing gear employed varies widely from state to state. Hand lines are used in New England when schools of large fish are feeding; pound nets are common in Chesapeake Bay; traps and seines are generally used in inshore waters; trawls and gill nets are used both inshore and offshore in many states. During the last decade, otter trawls, gill nets, and pound nets have yielded about three-fourths of the mid-Atlantic commercial catch, with seines and hand lines contributing most of the remainder (Mid-Atlantic FMC 1984). Spring, summer, and especially fall yield most of the recreational catch in the mid-Atlantic, but large fish are available year-round in the southernmost mid-Atlantic and the south Atlantic for anglers venturing offshore to the Gulf Stream (Wilk 1977). Spring-spawned young-of-the-year caught during the fall migration, and yearlings of both stocks caught during spring, are especially popular with novice anglers since they are plentiful in inshore waters.

Source: Woodshole Marine Biology

Revised: January 14, 2004