Species: Bass, striped

OTHER COMMON NAMES - striped bass, striper, linesider, bass, rockfish, rock, sewer trout and Fr. bar raye

Table of Contents:
OTHER COMMON NAMES
COMMENTS ON TAXONOMY
COMMENTS ON HABITAT ASSOCIATIONS
ANIMAL/PLANT SPECIES ASSOCIATIONS
HABITAT SUITABILITY MODELS
COMMENTS ON HABITAT SUITABILITY MODELS
FOOD HABITS
COMMENTS ON JUVENILE FOOD
COMMENTS ON ENVIRONMENTAL ASSOCIATIONS
COMMENTS ON LIMITING ENVIRONMENTAL ASSOC
LIFE HISTORY 
PHYSICAL DESCRIPTION
REPRODUCTION
BEHAVIOR
AQUATIC/TERRESTRIAL ASSOCIATIONS
SPECIES INTERACTIONS
COMMENTS ON MANAGEMENT PRACTICES

COMMENTS ON TAXONOMY -
A family of medium-sized to large, perch-like fishes, inhabiting coastal marine, brackish, and fresh waters in temperate and tropical regions of the world. Some species are anadromous.    Family of temperate basses; appears in earlier literature as Roccus lineatus.  Other common names include rock, rockfish, striper, linesides, sewer trout, Fr. bar raye. The generic name Morone is applied to this species, following revision of the group. Subpopulations along the Atlantic coast have been studied, using morphometric and meristic characters. Results suggest discrete populations exist in regions such as the Hudson River, but Chesapeake Bay waters may contain as many as four populations during the overwintering period. Studies of body depth and caudal peduncle depth values suggest north-south clinal variations. The population in the St. Lawrence River, now seriously depleted, was considered distinct.  

COMMENTS ON STATUS -
Coded Status: Sport Fish, Migrant, Commercial/consumption, Commercial.
Presently, Atlantic coast stocks of striped bass appear to be at an all time low.    Striped bass supports an important commercial fishery along the Atlantic coast, especially from Massachusetts through North Carolina; over 90% of the historical harvest derives from internal waters and the Territorial Sea. In 1974, striped bass were the second most important recreationally caught species but had nearly disappeared by 1980 and 1981 when the species comprised less than 0.5% of all East Coast recreationally caught fish.  The Striped Bass Fishery Management Plan (1984) was developed jointly by the Mid-Atlantic, New England, and South Atlantic Fishery Management Councils to provide for Federal management of the striped bass fishery in the fishery conservation zone (FCZ) in order to complement State actions in the Territorial Sea and internal waters.     A Striped Bass Fishery Management Plan for the Gulf States (November 1986) was developed to be used by the [Gulf] State and Federal agencies as the basis for their individual programs and regulations. In recent years striped bass have become a focal point of public attention in issues of environmental degradation, power plant siting, and management of interjurisdictional fisheries.  Striped bass are excellent eating fish and may be prepared in many ways.

Sport Fisheries are subject to following regulations: length limits of 28inches are enforced by all Mid-Atlantic states; NJ, NY, and CT have closed seasons. In general the species evokes disagreement between sport and commercial anglers and freshwater vs saltwater management agencies.

COMMENTS ON HABITAT ASSOCIATIONS -
The striped bass is an anadromous and coastal schooling species, inhabiting mainly inshore waters. Although typically anadromous, some populations may remain permanently in fresh water; others may migrate for many miles along the coast often moving into estuaries. The available evidence suggests that some bass, weighing 1.4-4.5 kg, move northward into Canadian waters in the spring, spend the summer in brackish or fresh water, and move southward again into United States waters in the fall. Tagging studies of United States populations have shown that some striped bass move northward and eastward from Chesapeake Bay and the Hudson River to the New England states in late winter and early spring. Some enter the Bay of Fundy and spend at least part of the summer in the lower reaches and estuaries of larger rivers such as the Saint John. Fish tagged in the Saint John River in 1964 were recovered off Massachusetts, New Jersey, Delaware, and Maryland. In the Saint John River, larger fish of 9.0-18.1 kg apparently move downriver into brackish water after spawning and move back upriver in the fall.  

ANIMAL/PLANT SPECIES ASSOCIATIONS -
Predation and Competition: Adult striped bass have few enemies. An esteemed sport fish in many areas, the chief predator is man. Water diversion and pollution in the rivers and estuaries they inhabit no doubt affect survival. Juvenile striped bass may be eaten by larger fishes such as Atlantic tomcod, Atlantic cod, silver hake, and larger striped bass.    

HABITAT SUITABILITY MODELS -
Riverine V1 Percent natural river discharge during spawning: maximum unknown; minimum habitat suitability decreases in proportion to the reduction in discharge; optimum 100%; Riverine V2 Maximum total dissolved solids (TDS) concentration during spawning: maximum 5 ppt (parts per thousand); minimum 0 ppt; optimum 0-0.18 ppt; Riverine V3 Average water temperature during the spawning season and period of egg development: maximum 22 C; minimum 13 C; optimum 17- 19 C; Riverine and estuarine V4 Minimum dissolved oxygen level during egg and larval development: maximum unknown; minimum 1 mg/l; optimum > 5 mg/l; Riverine V5 Average current velocity in water column during period of egg development: maximum unknown; minimum 29 cm/s; optimum 31-34 cm/s; Habitat Associations - 1 Estuarine V6 Percent original salt marsh in estuary: maximum 100%; minimum 0%; optimum 100%; Estuarine V7 Percent of original freshwater input (average volume) to estuary during the late winter and spring high flow period: maximum 100%; minimum 0%; optimum 100%; Estuarine V8 Average water temperature during period of larval development;maximum 23 C; minimum 12 C; optimum 18 C - 21 C; Estuarine V9 average salinity during period of larval development: maximum 15 ppt; minimum 0 ppt; optimum 3-7 ppt; Estuarine V10 Average dissolved oxygen during the growing season: maximum unknown; minimum 1 mg/l; optimum > 5 mg/l; Estuarine V11 Average water temperature during growing season: maximum 27.5 C; minimum 10 C; optimum 14-22 C  

COMMENTS ON HABITAT SUITABILITY MODELS -
Habitat suitability for adults limited primarily by water quality   ; asusmption for river discharge during spawning is that the optimal discharge is 100% of the natural river discharge for the spawning time period; discharges of greater than 100% are not thought to reduce suitability for spawning; reductions in discharge are assumed to result in proportional reductions in habitat suitability ; this model does NOT apply to marine environments.

FOOD HABITS -
As the striped bass grows, small fishes are eaten. In the sea, adults eat a wide variety of fishes such as alewives, herring, smelt, eels, flounders, mummichogs, rock gunnels, sand lance, silver hake, and silversides. They also consume invertebrates including squid, crabs, sea worms (Nereis), and amphipods and, along rocky shores, will take small lobsters. In rivers and lakes, food organisms are similar and other small fishes are taken when available. American shad is reported to be a common food item in the Chesapeake Bay region but no evidence of its consumption in Shubenacadie River, NS was found in Leim's investigation in 1924 but was found to be the  chief food during shad migrations by Davidson in 1950. Feeding ceases for a brief period before spawning and during the spawning period.  

COMMENTS ON JUVENILE FOOD -
In a CA lake, threadfin shad made up 45% vol. of diet. In OK culture ponds, bass 10-30mm standard length ate mainly copepods, bass 30mm ate more Cladocera & insects, fish not included in diet till bass reached 69mm, not impt. part of diet till bass 90mm. In VA culture ponds, Cladocerans, copepods, insects important, Cladoceran abundance in stomachs increased when bass were 30-40 mm total length. Food consumption changes when fish are juveniles to include primarily small shrimps (Gammarus and Crangon), other small crustaceans, annelid worms, and insects.    Fish become increasingly more important in the diets of juvenile striped bass larger than 100 mm, and by age II striped bass are primarily piscivorous.

COMMENTS ON ENVIRONMENTAL ASSOCIATIONS -
Striped bass populations along the South Atlantic coast of the United States are primarily endemic and riverine and apparently do not undertake the extensive coastal migrations that are typical of stocks in the Middle and North Atlantic. Striped bass require waters having suitable flows, salinities, temperatures, and other aspects of habitat quality, which make the species particularly vulnerable to river alterations. Such alterations have eliminated the native Gulf of Mexico striped bass from most of its 00160S=optimal river flow is 100% natural flow   ; 00170S=minimum velocites needed to maintain suspension of eggs is 30 cm/s   ; 00030S=dissolved oxygen less than 1.7 ppm  795 ; 00060S=optimal range of total dissolved solids 100-900 ppm.

COMMENTS ON LIMITING ENVIRONMENTAL ASSOC -
Striped bass concentrate in areas with DO of at least 6 mg/L. Subadult and adult striped bass prefer water temperatures of 20-22 C and avoid temperatures of > 25 C if cooler waters with DO > 5mg/L are available. Increased DO in the cooler, deeper waters of upper Chesapeake Bay would restore suitable summer habitat for adult and subadult striped bass.

LIFE HISTORY 

PHYSICAL DESCRIPTION: Striped bass are silver overall and dark olive green gray on the back with 7 or 8 black horizontal stripes along the sides; Teeth on base of tongue in parallel patches. Body depth less than 1/3 length; back not arched; dorsal fins separate (distinguishes from M. chrisops and M. americana, 2 sharp spines on preopercle (characteristic of genera). Young (15-20)mm FL and larger) distinguishes from M. americana by body depth (M. saxatilis more slender) 2nd anal spine thicker than 3rd (but not thicker than 1st, narrow anal fin (as M. americana). Females generally grow larger than males. Ind. > or = 13.6 kg are female.

REPRODUCTION: Females reach maturity at 3-4 years and at total lengths of 432-437 mm; males mature at 2 years and 174 - 254 mm total length; larval stage last (35-50 days); larvae begin active feeding at 8 days (6-7 days); juvenile stage lasts from 35-50 days to maturity.

Spawning always occurs in spring in fresh water, in most cases relatively far upriver but occasionally just beyond the head of tide. Potential spawners usually move upriver in the fall. In the Bay of Fundy and Gulf of St. Lawrence watersheds spawning occurs in May and June. After a fall migration up the St. Lawrence River prespawning fish moved upriver in spring and usually spawned in June. Formerly some large fish have been taken as far up the river as Lac St. Louis, at Montreal. In Belleisle Creek, Saint John River system, NB, spawning runs were noted inMay . In the Kouchibouguac river, in the Northumberland Strait region, NB, it was observed that a portion of natal spawners overwintered in the upper portion of the river, dropped down to the estuary in early April when the river was free of ice, and moved back upriver in mid-May to spawn. Water temperature at the time of spawning varied from 12.0 to 14.5 C. It was noted that maximum spawning activity in the Saint John River population took place at a water temperature of 14.5 C. Collections of striped bass eggs in the Annapolis River, NS, indicated spawning occurred there in early June and was closely related to water temperature on the spawning grounds. Spawning occurred mainly at temperatures of approximately 18 C and ceased temporarily when the temperature dropped to 15-16 C. The eggs are semibuoyant, have a large oil globule, and measure about 1.0-1.35 mm in diameter before extrusion, and about 3.6 mm a few hours after fertilization. Larger females produce more eggs. Hatching occurs in 70-74 h at 14.4-15.6 C and in about 48 hour at 17.8-19.4 C. Little information is available on juvenile striped bass in Candian waters. Spawning begins in mid-February and can extend to June or July; young females produce between 14,000-65,000 eggs; older females may produce up to 5,000,000 eggs   ; spawning activity may slow from 1 to 3 peaks; these peaks are apparently associated with increases in water temperature   ; eggs are spherical,- semi-buoyant, non-adhesive, and approximately 1.3 mm in diameter at fertilization at 22 C or about 80 hrs. after fertilization at 11 C; larval stage divided into 3 phases, yolk sac (3-9 days; 5-8 mm TL), finfold (metamorphosing stage)(11 days; 12 mm TL), and post fin-fold (20-30 days; 20 mm TL)  ; factors influencing reproduction and survival of eggs: (1) water level fluctuations, (2) wind and wave action, (3) water quality, (4) aquatic and terrestrial cover, (5) air and water temperature, (6) Life History invertebrate and fish predation, (7) human activity  ;

BEHAVIOR: Tend to school by size rather than age. Leave bays and join coastal migrations at age 2-3, moving north in Summer and south in Winter; More than 50% of Atlantic coast catch originates from spawning grounds in Chesapeake Bay. These groups are rarely more than few miles offshore. Distance travelled appears related to size and age (the larger/older, the farther) for Chesapeake Bay fish. Feeding is not continuous and within schools is often synchronized.

SPECIES ORIGIN WITHIN STATE: native to Atlantic coast and ascendable tributaries, introduced to many reservoirs;

LIMITING FACTORS: limiting factors on larval survival include predation and water quality factors ; 

AQUATIC/TERRESTRIAL ASSOCIATIONS: predators of larvae include aquatic insects, bluegill, green sunfish, crappie, flathead minnow, mosquitofish;

POPULATION PARAMETERS: growth inversely related to population density, curvilinearly related to forage crop, food dependent at low food availability, food independent at high food availability  10 ; elements to model a bass population in a reservoir: (1) need minimum of 25 lbs. per acre of predator (bass), (2) need minimum of 75 lbs./acre of plankton feeders (i.e., shad), (3) need minimum of 100 lbs./acre of bottom feeders (i.e., catfish), production of these three factors controlled by: fertility of water, climate, water level fluctuations, shape of basin and substrate composition ; biological factors which influence early life stages: (1) size of spawning population, (2) predation and cannibalism, (3) disease and fungi--important in hatcheries, not important in wild populations, (4) starvation--important in hatcheries, not evident in wild populations; factors to estimate standing crop of bass: (1) water depth and area of watershed and area underwater, (2) fertility of water and watershed, (3) species composition of system, (4) population estimate, (5) average seasonal water temperature, (6) length of growing season; water quality is definitely limiting, cold December temperatures and spring flows very important in predicting success of following year class (cold December temperatures and freeze veg in place for spring movement stops flow moves detritus to nursery area, where stimulate zooplankton bloom.

SPECIES INTERACTIONS: Predators: bluefish and weakfish. On larvae: white perch and copepods, Likely competitors: bluefish, weakfish, white perch

OTHER: life stages: (1) egg: stage from ova fertilization to hatching (includes embryo, fluids, and chorion--shell), (2) larva (fry): hatching to dispersal from nest (includes yolk sac absorption and pigmentation formation), (3) fingerling (young-of-year): dispersal from nest to adult (first season or first year of life), (4) adult: post-fingerling stage, after first year, may or may not be reproductive  Aluminum toxity induced by pH ;No detectable effect of [ ] 200-400mg/l at pH7 at pH6, pH5 or less, Al[ ] of 25- 100 mg/l caused sign, mortality depending on lifestge. Cadmium most toxic, LC 50 of .001ppm cadmium chloride for larvae. Total residue chlorine have sublethal sign effects (larvae sign, shorter body lengths after exposure of eggs to .15ppm Extensive work has been done on toxity of pesticides and other substances to larvae.

PARASITES AND DISEASE: Information available regarding the parasitic fauna in Canadian coastal waters is limited. The prevalence and intensity of metazoan parasites from 17 specimens was investigated in anadromous striped bass from the Kouchibouguac River, NB, and reported on trematodes Homalometran pallidum, Lepocreadium setiferoides, and Stephanostomum tenue; acanthocephalans, Echinorhynchus gadi and Neoechinorhynchus rutili; and the nematode Philometra rubra. The parasites were found in most cases in over half of the specimens examined and were parasitic in the stomach, intestines, and body cavity. Homalometran pallidum and N. rutili are new host records. A northern range extension record for the copepod Ergasilus labracis to Minas Basin and Northumberland Strait has been reported.   

SPAWNING: Striped bass spawn during the spring in tidal fresh or brackish waters. The principal spawning and nursery areas of striped bass along the Atlantic Coast are found in the Chesapeake Bay and its tributaries and the Hudson and Roanoke rivers. Within the Chesapeake Bay basin, major spawning areas include: the James, Pamunkey, Mattaponi, Rappahannock, Patuxent, and Potomac rivers on the western shore; the head of the Bay with the Susquehanna Flats, Elk River, Chesapeake and Delaware (C&D) Canal; and, the Choptank and Nanticoke rivers on the Eastern Shore. Spawning activity is apparently triggered by a rise in water temperature. Spawning times may vary from year to year due to annual temperature variations. In the Chesapeake Bay, 1 to 3 peaks occur during each spawning season with the major peak occurring any time during the last half of April or the first week of May. Research has suggested that freshwater flow (both velocity and volume) is related to successful spawning. Toxicity: Water quality data from an on-site toxicity experiment on the Nanticoke River implicated that aluminum toxicity was induced by low pH. Striped bass exhibited no detectable effect from aluminum concentrations of 200 to 400 ug/l at about pH 7. However, a pH of 6.5 or less with aluminum concentrations in the range of 25 to 100 ug/l caused significant mortality dependent upon the life stage of the striped bass. Comparing the relative toxicity of copper and zinc on embryos, copper was more toxic, with a 48 hr LC50 value of 0.74 ppm. In a test of the tolerance of larval striped bass to cadmium, copper, and zinc, cadmium was the most toxic. Larval striped bass experienced 50% mortality when exposed to 0.001 ppm of cadmium chloride for 96 hr. Data indicate that levels of total residual chlorine (TRC), while not necessarily lethal, may have significant sublethal effects on striped bass. For example, striped bass larvae exhibited significantly shorter body lengths after eggs were exposed to 0.15 ppm of total residual chlorine. Striped bass eggs exhibit 50% and 100% reduction in hatch rate when exposed to 0.19 and 0.43 ppm of TRC, respectively.

COMMENTS ON MANAGEMENT PRACTICES -
Striped bass stocks have declined drastically in the past decade. This decline is generaly associated with reduced recruitment. The causes for the recruitment decline presently have not been determined but can be considered primarily to be overfishing, pollution, habitat loss, and/or natural causes. Maintenance of adequate spawning areas with good water quality is the most critical necessity for continued survival of striped bass according to some.    Reasons for the decline of native striped bass along the northern Gulf coast are speculative. Environmental alterations in the form of water control structures and extensive channelization may have prevented successful reproduction. Industrial and agricultural pollution have also been implicated as probable causes of the drastic decline of striped bass. The Fishery Management Councils are deeply concerned about the effects of marine habitat degradation on fishery resources as well as freshwater/estuarine habitats used by diadromous fishes such as striped bass. The following recommendations are made:
1. All available or potential natural habitat for anadromous striped bass should be preserved by encouraging management of conflicting uses to assure access by the fish to essential habitat and maintenance of high water quality standards to protect striped bass migration, spawning, nursery, overwintering, and feeding areas. Spawning and nursery areas are targeted as the most critical areas.
2. Filling of wetlands should not be permitted in or near spawning and nursery areas. Mitigating or compensating measures should be employed where filling is unavoidable. Project proponents must demonstrate that project implementation will not negatively affect striped bass, its habitat, or its food sources.
3. Best engineering and management practices (e.g., seasonal restrictions, dredging methods, disposal options, etc.) should be employed for all dredging and in-water construction projects.
4. Further blockage of rivers (either physical or chemical) preventing striped bass from reaching their historical spawning grounds should not be allowed. Adequate two way fish passage facilities must be employed where dams are constructed. Restoration should be attempted in the areas where blockage now occurs.
5. The combinations of man induced contamination which result in oxygen levels less than an average daily value of 6.0 mg/l or to a level below a minimum of 5.0 mg/l at any time should not be allowed in striped bass spawning and principal nursery areas.
6. The disposal of sewage sludge, industrial waste, and contaminated dredged material in striped bass habitat including the New York Bight should not be allowed.
7. The siting of industries requiring water diversion and large-volume water withdrawals should be avoided in striped bass spawning and nursery areas.
8. Except in designated mixing zones, heated effluent should not be discharged which would cause temperatures to exceed 85 F, or which would cause the temperature to be raised by more than 4 F during September through May, or to be raised by more than 1.5 during June through August. Facilities should not be located in striped bass spawning or principal nursery areas. Heated effluent dischargers should not intentionally shut down operations during Novermber through March and, if shut downs must occur, they should be gradual in order to avoid reverse thermal shock to striped bass.
9. Dechlorination facilities or lagoon effluent holding facilities should be used to destroy chlorine at sewage treatment plants and power plants.
10. No toxic substances in concentrations harmful to humans, fish, wildlife, and aquatic life should be discharged.
11. The EPA and States should review their water quality standards relative to striped bass spawning and nursery areas and make changes as needed.
12. The EPA and States should establish water quality standards for the coastal zone specifically with respect to the habitat requirements of striped bass migratory passage and overwintering.
13. The EPA should establish water quality standards for the FCZ sufficient to maintain edible striped bass.
14. Water quality standards in spawning, nursery, overwintering, and areas of migratory passage should be enforced rigidly by State or local water quality management agencies, whose actions should be carefully monitored by the EPA.
15. Appropriate measures must be taken as soon as possible to reduce acid precipitation and runoff.
16. EPA must establish and approve criteria for vegetated buffer strips in agricultural areas adjacent to striped bass spawning and nursery areas to minimize pesticide, fertilizer, and sediment loads to these areas critical for striped bass survival.
17. It is necessary that scientific investigations be conducted on striped bass to emphasize the long-term, synergistic effects of combinations of environmental variables on, for example, reproductive capability, genetic changes, and suitability for human consumption.
18. For recommendations for future investigations,  Stocking - are stocked in Missouri as a contribution to the fishery & to utilize gizzard shad. Popular forstocking since they grow rapidly, attain large size, & utilize abundant shad. In the southeastern U.S., stocking fingerlings is generally the most satisfactory method . Must have suitable spawning areas if pop. is to be self-sustaining  Hybridization - in a TX res., white bass X striped bass hybrids grew rapidly & had high survival, the recreational benefits of stocking hybrids surpassed the costs. White bass X striped bass hybrids had faster early growth and higher survival than striped bass  Culture - an OK pond culture recommended 1. Provide abundance of copepods early in season, and Cladocerans & insect larvae late in season, 2. Delay adding forage fish till striped bass are 4-5 long, 3 soft-rayed fish of fusiform body shape are best forage. In AL, striped bass culture in continuously aerated ponds produced 2.4X the no. of fingerlings produced by conventional methods. In OK, plankton was used as food in the hatchery prior to release into culture ponds. In AL, best response to feeding obtained when surface water temp. 10 deg. C. Avg. survival, mean production & food conversion of fingerlings were best at the following feeding rates 10% of body wt. July 7-31, 7% body wt. Aug. 1-31, 6% body wt. Sept. 1-30, 5% body wt. Oct. 1-31  4923  In OK, striped bass preyed on trout after trout stocking. An IL study concluded that striped bass are well-suited to be a pond-reared food fish. One study recommended managing only dominant year-classes to optimize yields.  Sport fisheries are subject to the following regulations: length limits ranging from 12 to 18 inches (minimum) are enforced by all mid-Atlantic states; NJ, NY, & CT have closed seasons. MD requires all 15 pound + caught in spawning season be released. In general, the species evokes disagreement between sport & commercial anglers and between saltwater and freshwater management agencies.

A list of recommendations in the Chesapeake Bay include:
1. Increase dissolved oxygen
2. Improve water quality in spawning areas
3. Determine hatchery contributions to spawning stocks
4. Quantify estimates of young-of-the-year recruitment
5. Protect spawning stocks

Source: Woodshole Marine Biology, Date 27 AUG 96

 Revised: 07/10/2002