Food and Agriculture Organization of the United Nations Fisheries and for a world without hunger Aquaculture Department

Cultured Aquatic Species Information Programme Morone hybrid (genus Morone, hybrids)

I. Identity V. Status And Trends a. Biological Features VI. Main Issues b. Images Gallery a. Responsible Aquaculture Practices II. Profile VII. References a. Historical Background a. Related Links b. Main Producer Countries c. Habitat And Biology III. Production a. Production Cycle b. Production Systems c. Diseases And Control Measures IV. Statistics a. Production Statistics b. Market And Trade

Identity

Morone genus Morone, hybrids [Moronidae] FAO Names: En - Striped bass, hybrid, Fr - Bar d'Amérique, hybride, Es - Lubina estriada, híbrida

Biological features

The fishes that make up the hybrids of the genus Morone are all within the Moronidae family, which is a small group of freshwater (white bass and yellow bass) and anadromous estuarine (striped bass and white perch) and marine percoids (striped bass) found naturally from the Mississippi River drainage system to the East Coast of the United States and Canada. Also included in this family are the European-North African species of Dicentrarchus represented by two species (D. labrax and D. punctatus). There is only one reported case of intentional congeneric cross hybridization between the two genera and the offspring were not viable or were triploids.

The general features of Morone include having a medium to large size; the body is either moderately deep or elongate and terete or compressed dependent on the species (in striped bass the body depth is less than of body length, and it is more than in the other species and hybrids; the mouth is moderate to large with a terminal lower jaw jutting forward of the snout; opercules have at least one well-developed spine; maxillary teeth are small and there are one to two hyoid tooth patches on the tongue; scales are ctenoid and the lateral line is complete extending into the caudal fin; there may or may not be several lateral stripes found on the fish that

FAO Fisheries and Aquaculture Department may be complete or broken in appearance; dorsal fins are separate or slightly joined with fin spines stout that vary among species but typically are 7-8 in first dorsal and one anterior in second dorsal that may be joined or separate, there are 3 spines in the anal fin of varying length that is species dependent; the caudal fin is emarginated or forked dependent on the species; and, the pelvic fin is thoracic with the pectoral fins located high on the side. The hybrids of Morone are intermediaries of the parental species and typically deeper in body than striped bass with 7-8 broken stripes laterally found on the sides.

Size differences are significant in that the white bass, white perch, and yellow bass are small; maturing in the 0.5 kg range with record fish being approximately 3 kg, 1.38 kg, and 1.36 kg, respectively. Netted striped bass, however, have been reported in the range of 54.5 kg with the record fish caught on fishing tackle being 31.8 kg for a freshwater system and 37.2 kg for saltwater: over 10 times the size of white bass. The record hybrid fish caught by angling was 12.5 kg.

Images gallery

Hybrid eggs 2.5 hours post fertilization. Larval hybrid striped bass at hatch. Photo by R. M. Harrell Photo by R. M. Harrell

First feeding larvae. Photo by R. M. Harrell

Fingerlings. Photo by R. M. Harrell (modified) Live harvested hybrid striped bass. Photo by D. W. Webster

Profile Historical background

Although one of the pure parents of hybrid Morone, striped bass, have been artificially cultured since the 1880s, Morone aquaculture really did not become established as a science until the 1960s. Prior to that time, production was essentially dependent on one hatchery system in the coastal area of the Roanoke River, North Carolina in the United States This hatchery was dependent on collecting naturally-ovulating female striped bass and spermiating males on the spawning grounds just below the hatchery location.

By 1962 hormone-induced spawning of striped bass was successful in South Carolina, and by 1965 the first Morone hybrid was artificially made by combining the eggs of striped bass with the sperm of white bass

FAO Fisheries and Aquaculture Department creating a palmetto bass. The original objective to produce the hybrid was to provide a fish that could occupy the open-water areas of these new reservoirs the same way white bass typically do, but had the potential to obtain the size of a striped bass and create an open-water fishery. Coupled to this logic was the failure of striped bass to do well in the relatively shallow, warm-water, man-made reservoirs; which is prime habitat for the white bass. Management biologists were hoping to capitalize on the anticipated increased vigor often found in hybrid crosses, and they were looking for a fish that would be more tolerant of warmer temperatures, lower oxygen concentrations, and smaller sized reservoirs (<500 ha) that had been proven to be barriers in establishing inland striped bass populations.

Ultimately, it was confirmed that hybrid Morone did indeed exhibit hybrid vigor, had excellent potential for management, and they produced an exceptional recreational fishery. Today, with the exception of Alaska and Idaho, 48 of the 50 States have natural or introduced populations of striped bass or its hybrids. These fish are a popular recreational fish and over 200 million fingerlings (40-125 mm) are produced annually in the United States for stocking.

Aquaculture for hybrid Morone food-fish production began in the United States in the 1970s when in 1973 the first commercial hybrid striped bass production facility was started. They produced about 9 000 kg but failed in 1974. In 1977 a second farm was established and produced around 13 200 kg, but it also failed within three years. By 1980 several farms were in operation and in 2000 annual production was approaching 5 000 tonnes. Production in Asia began in 1996, while production in Europe began in 2004.

Main producer countries

Many countries have produced hybrid Morone, but the United States is the most significant producer. The other main countries involved in hybrid Morone production include Mexico, Portugal, France, Germany, Italy, Israel, South Vietnam, China, Taiwan, and Russia.

According to FAO statistics (2013) the producers countries are United States, Israel and Italy, as shown in the map below.

Main producer countries of striped bass, hybrid (FAO Fishery Statistics, 2013)

Habitat and biology

The various hybrids of Morone have different requirements for larval-rearing, and are strongly linked to the female parent of the cross. Once the fish are readily accepting artificial diets the production methods are similar regardless of the parental species. Production is divided into different phases; hatchery (seed supply), fingerling production (nursery), and grow-out (ongrowing).

FAO Fisheries and Aquaculture Department Morone are eurythermic (4–30 oC). Fingerling production and grow-out to market-size fish allows for much more flexibility in biological requirements, while larval rearing is more exacting. All Morone are dioecious, group-synchronous, iteroparous, spring spawners mostly in freshwater tributaries and in coastal areas above the tidal zones. Spawning is usually initiated with increasing spring water temperature and ranges from 12–24 oC with peak spawning being around 18–20 oC. All Morone spawn in freshwater.

Traditionally, wild-caught fish from natural spawning grounds were used as broodstock for all Morone culture including making hybrids. Because the females were naturally close to spawning only administration of ovulatory hormones, such as human chorionic gonadotropin, was needed to stimulate ovulation. However, in recent years, the life cycle has been closed and using a combination of maturation hormonal implants and photoperiod manipulation, most Morone can be induced to spawn at least twice per year.

In nature, striped bass and white perch are pelagic spawners while the other Morone spawn near shore, usually around vegetation and/or rocky substrates. Striped bass, white perch, and hybrid eggs are non-adhesive and demersal with a specific gravity greater than freshwater. White bass and yellow bass eggs are adhesive. Mature striped bass eggs are about 1.5 mm in diameter while white bass eggs are about 0.75 mm. A water flow of approximately 30 cm/sec is required for keeping the striped bass and palmetto bass eggs in suspension. Egg development is fast and usually requires about 36 hours to hatch at 20 oC.

Newly hatched larval striped bass (prolarvae) are typically 4–7 mm in total length (TL) while white bass larvae are considerably smaller (ca. 3–5 mm TL). The larvae of hybrids are closer to that of striped bass than white bass but are highly dependent on the female of the cross. Larval Morone have a yolk sac that contains a large oil globule that helps maintain buoyancy in the water column. Mouth parts are typically developed by 3–5 days post-hatch and they begin feeding on small zooplankton.

Rarely do first-feeding larval Morone accept artificial food. Therefore most the nursery production of fingerlings is usually a separate segment of the aquaculture of the species and their hybrids and is conducted in outdoor pond systems where natural zooplankton populations are manipulated and managed. Due to size differences of the larvae and exacting live food size requirements rarely are there completely closed life-cycle operations. Larval white bass, white perch, yellow bass and hybrids of these crosses with the female being the parent require very small zooplankton (i.e., rotifers) for first feeding. Larval striped bass and palmetto bass hybrids can be started on first instar nauplii of Artemia. All Morone larvae do better with their first food sources containing high levels of highly unsaturated fatty acid enrichments; especially EPA and DHA.

Preflexion larval (hatch–12 mm) Morone and hybrids quickly develop into postflexion fry (12–25 mm), then fingerlings (>25 mm), with the latter having complete fin complements, usually within 30 days post-hatch dependent on food availability and temperature. As they grow they typically have a down-stream movement, especially striped bass and white perch. In coastal areas striped bass and white perch enter the estuaries and spend most of their life there, moving upstream to spawn annually once mature. In some coastal river systems larger striped bass, especially females, move off-shore and migrate up and down the East Coast of the United States overwintering before moving back into estuaries and freshwater tributaries to spawn in Spring. There is an introduced striped bass population on the West Coast of the United States that follow a similar pattern. There are no reports of hybrid Morone being captured in near-shore coastal waters.

In broodstock hatchery operations mature fish (both striped bass and white bass for hybrid production and parental stock domestication and selection) are maintained at low densities in 3-10 ppt salinity and fed high- quality protein and fat diets. Water quality is maintained by filtration, ozonation, oxygenation, and degasification. Photoperiod and temperature is controlled and appropriately manipulated along with hormonal implants to cycle spawning. Production Production cycle

FAO Fisheries and Aquaculture Department Production cycle of striped bass, hybrid

Production systems

The production systems of hybrid Morone culture are very specialized and typically broken down into three stages: seed (hatchery production), nursery (fingerling production), and ongrowing (grow-out). The seed stage lasts days to weeks unless controlled, out-of-season production is occurring; then it can be a year-round process. The nursery stage lasts 1–10 months dependent on whether a phase I (30–75 mm) fish or an advanced phase II fingerling (100–200 mm) is required. The ongrowing stage is market driven (typically 0.75–1.5 kg) and can take 10–24 months or more depending on size required and production system (indoor vs. outdoor) used. Seed supply Because the target fish of this information sheet is a hybrid between two species of Morone the only source of seed is by artificial production from a hatchery system. The two major crosses of hybrid Morone are the palmetto bass (striped bass ♀ X white bass ♂) and its reciprocal cross,sunshine bass (white bass ♀ X striped bass ♂). These two crosses will be the example of production discussions of hybrid from this point forward.

Regardless of the cross produced, hybrids must be made by manually stripping the eggs from the female of choice and then manually fertilizing them with sperm from the male of choice as volitional tank spawning rarely occurs to make F1 hybrids. The dry method of fertilization is the preferred method because once water is added sperm motility is very short-lived (usually less than 2 minutes). Gynogenetic and triploid hybrid Morone have been created, but the process is technical and beyond the scope of this report.

Historically, these crosses were made with broodstock collected from the natural spawning grounds in the spring of the year (late February to early June dependent on location). In the past decade or so, however, many hatcheries have been developing their own lines of broodstock and are becoming less dependent on gravid, running-ripe, wild broodstock. This shift is especially true where the parental Morone are not a native species

FAO Fisheries and Aquaculture Department and not readily available. Some hatcheries are also using domesticated fish in concert with photoperiod and hormonal manipulation to conduct out-of-season spawning.

Once fertilized, the egg incubation of hybrid Morone typically occurs in MacDonald hatching jars, which minimizes space requirements. Domesticated seed suppliers producing palmetto bass have an advantage due to the size of the eggs and the fact that striped bass eggs are non-adhesive, which lend themselves to circular tank incubation options. Also palmetto bass larvae are larger at first feeding thansunshine bass (see below).

Given that white bass eggs used to makesunshine bass are adhesive there are limitations to incubation systems, which require some means to break-down the adhesive matrix surrounding the eggs (i.e., tannic acid treatment 150–300 mg/L for 7–12 minutes). This step in incubation is important because of the probability of fungi attacking dead eggs and spreading to viable eggs during incubation, which can cause catastrophic losses. There is no approved treatment for these fungi for fish in the United States. Thus, use of tanks for incubation ofsunshine bass, while possible, is more problematic. Whensunshine bass eggs are incubated in MacDonald jars and the resultant embryos hatch they swim up and out of the jar into an aquaria set-up with a standpipe and a mesh screen of appropriate size to prevent loss of larvae down the drain. Diligence must be provided to prevent the fine-mesh screen from clogging and the water overflowing the standpipe.

Regarding choice ofsunshine bass versus palmetto bass as the hybrid of choice there are several considerations. Palmetto bass have larger eggs and resultant larvae, and therefore at first feeding are able to consume first instar Artemia nauplii. Conversely,sunshine bass larvae must be started on a smaller live food supply, usually rotifers at a density >300 rotifers/L. This prey-size difference is important because rotifers are more expensive and complicated to raise than Artemia, and thussunshine bass are harder to grow in indoor tank culture. Secondly, female striped bass yield hundreds of thousands of eggs, whereas female white bass produce only tens of thousands, and therefore fewer striped bass females are needed to produce the same number of larvae of palmetto bass. Regardless of these two positive aspects of palmetto bass, thesunshine bass is the hybrid of choice for seed suppliers because female white bass mature faster (average of 2.5 years versus 4-6 for striped bass females), they are easier to handle in spawning, and their ovulation is less synchronous (once a female striped bass ovulates all the eggs are spawned completely within a very short window so timing of ovulation is crucial). Also, a majority of male striped bass are mature at 2 years of age.

At hatch, bothsunshine bass and palmetto bass larvae have an endogenous source of energy in the yolk-sac and oil globule. This stage is known as prolarvae. In reality, due to size differences in overall total length, the time between endogenous and exogenous feeding is similar among the two crosses: 4–5 days post-hatch at 20 oC.

Typically, prolarval hybrid Morone are kept in hatchery systems until the mouthparts are developed and the larvae begin to feed on live food sources (4–7 days post hatch dependent on temperature). It is not unusual for prolarvae to be shipped to nursery producers such that when they arrive they are close to or ready to initiate exogenous feeding. Nursery Essentially all of the phase I stage of hybrid Morone nursery production is conducted outdoors in specialized earthen ponds. These ponds are specifically designed to drain easily into a catch-basin either located within the pond proper or at the exit of the drainage system. Supply water is almost always from natural freshwater or brackish (< 10 ppt) sources because it has a readily available source of zooplankton that is critical for larval survival success. It is essential, however, when using natural water systems (rivers, ponds, lakes, or estuaries) that the incoming water be filtered with a fine-mesh screen (200-400 µm to prevent the introduction of other fish eggs or larvae that may prey upon the hybrid Morone larvae), and that timing of stocking the nursery ponds coincides with the early successional patterns of zooplankton dynamics progressing from rotifers to cladocerans and copepods. Thus, not only does the water source need to have the right zooplankton populations as an inoculate seed source, the pond must be appropriately fertilized to manage the phytoplankton-zooplankton dynamics.

FAO Fisheries and Aquaculture Department Because Morone larvae are sensitive to light and variations in water quality, stocking is usually done at twilight when pond oxygen levels are still high. Tempering of shipping water with pond water is critical; especially with regard to temperature, salinity, and pH. Stocking densities are dependent on the size needed at harvest. For phase I production, larval stocking densities range from 125 000–1 000 000 larvae per hectare with 30–60 day harvest sizes of 25–40 mm and 450–3 500 fish/kg. The smaller densities yield larger fish but there is usually a larger size diversity of the fingerlings. Most ongrowing producers want larger fish for stocking so the lower densities yielding the larger fish at harvest are the typical approach. Each nursery producer understands what their pond systems will yield in time, size, and quantity of fish.

The major limitation on phase I production in length of time is in relating prey size and availability to growing fingerlings. Once the fish reach the 40–50 mm size (~1 g) they switch from planktivorous feeding to a piscivorous nature and begin cannibalizing each other. Here it is crucial to either train the fish to feed on artificial diets while still in the pond or harvest and grade the fish and train them to feed in indoor tanks.

Traditionally, once phase I fish are harvested, graded, and trained to feed they can be restocked for phase II production to produce larger-sized fish (75–250 mm), stocked directly into tanks for intensive production, or graded and stocked directly into grow-out ponds (avoiding phase II production) to produce market-sized fish. This latter method is known as direct stock.

Direct stock can be accomplished by selecting out the larger (~3 g) fish from phase I production that invariably results from differential growth or the smaller phase I fish are held until they reach ~3 g and are graded for uniform size and then stocked into final grow-out ponds. Once the 3 g fish are stocked into grow-out ponds they must be trained or retrained to accept artificial diets in the pond and fed until they reach market-size (18– 24 months). Direct stock avoids harvesting phase II fish, which is a costly step in labour and potential loss of fish due to additional excessive handling and stress.

The traditional method requires grading the fish and training them to accept artificial diets “in house” then restocking phase I fish (~1.5–2 g) in the same phase I ponds from which they were harvested then fed and held for up to 10 months when they are then harvested before the next phase I nursery season. Stocking densities for the traditional phase II production are in the 10 000–250 000 fish/ha range (most producers stock in the 25 000–60 000 fish/ha range) and density is related to desired size at harvest (i.e., lower densities yield larger size fish). Stocking densities in the direct stock method are approximately 9 250–10 000 larvae per ha because these fish will not be harvested until they reach market-size (ca 0.75–1.5 kg).

The traditional phase II production has an economic advantage in that it affords the use of the specialized nursery ponds year-round where the second phase of production yields smaller numbers but higher value fish owing to size. During phase II production and direct stock strategies, as long as fish are feeding (usually temperatures above 16 oC) they are fed at least once daily with a high protein (30–50 percent), high fat (10–16 percent). The goal is to get as much growth as possible within this growing the fish can “overwinter” with minimal mortalities and/or weight loss. Outdoor feeding usually ceases when water temperatures get below 6 oC.

Typical phase II harvest size initially stocked at densities in the 20 000–30 000 larvae per hectare range (stocked at a size of ~650 fish/kg) yield fish in the 125–225 g range. Obviously a trade-off exists between phase II production and the direct stock method with respect to biological maximum growth and economic maximum growth. These variables are site and operator dependent. Ongrowing techniques Over the past 10 years 70–90 percent of all ongrowing methods of hybrid Morone has occurred in earthen ponds. Regardless of whether the producer is using the direct stock method or stocking phase II fish, the goal is to reach market size before the end of the second growing season. Based on a mean survival of 80 percent, yield per production pond typically ranges between 1.6 and 1.7 tonnes.

FAO Fisheries and Aquaculture Department Because of the carrying capacity of the pond supplemental aeration is essential. Supplemental aeration can be in the form of paddlewheels, airlift pumps, bubbler systems or even adding freshwater from an external source. All these supplemental efforts impact economic yield as they either run off electricity or diesel fuel, which must be factored in production costs.

When the pond carrying capacity is being approached water quality is crucial. Shifts in unionized ammonia, pH, nitrite and even total gas saturation can lead to stress and mortality. Stressed fish tend to cease feeding and become susceptible to secondary disease infections. Constant attention must be provided at all stages of production.

Stocking densities for ongrowing techniques are similar to that for direct stock approaches (9 250–10 000 fish per ha). Second-year growth of hybrids should yield 1 kg fish by 18 months of production from larvae to market.

In the United States in 2014 about 17 percent of the fish were produced in closed or semi-closed recirculating aquaculture systems where water quality, temperature, oxygen, and feeding was carefully controlled. Under these conditions fish typically reach market-sized fish in 10–12 months because the fish are still growing during winter months where fish in ponds essentially cease growth. Stocking densities are system and redundancy back-up systems dependent and are too specific to be covered here. Likewise in 2014 about 2 percent of the market-size hybrid Morone production occurred in cage culture. Because fish in cages are exposed to the same weather conditions as those in ponds their typical grow-out times are similar. Stocking densities are also site, cage or net-pen size, and back-up aeration capacity dependent and is not covered here. Harvesting techniques Harvesting phase II fish is accomplished in the same manner as phase I fish. The pond is dewatered and the fish are collected in a catch basin with nets, graded, and placed on transport trucks to be taken to the grow-out producers or to a holding facility for later shipping. If the pond is too large and expensive to dewater other options to harvest include using large haul seines. Haul seines can be size selective and, dependent on the mesh size used, a population can be “thinned” periodically to maintain uniform size. This technique is useful with hybrid Morone owing to their hybrid vigor and faster growth rates. In using haul seines, boom-loaded baskets dip the concentrated fish out of the nets and then loaded on a transport trucks, or the fish are crowded into a fish pump or fish.

Ongrowing fish harvest is often carried out over several months. In tank and cage-culture systems harvest is simple wherein fish are crowded by screens and netted out for thinning or complete harvest, grading, and, ultimately, processing. In pond systems fish are harvested by use of a 4 cm or larger, soft-mesh, knotless seine. Using the smaller mesh size all market-sized fish will be captured and smaller than market-size fish will escape through the mesh. Market-sizes range from small (0.5–0.7 kg), medium (0.7–1.0 kg), and large (>1 kg) fish. Using larger mesh seines affords the opportunity to be size selective and respond to market demand. Partial harvest affords the smaller fish the opportunity to continue to grow without undue competition from the larger fish. Partial harvest also provides fish availability over a longer period.

On-grown fish can also be harvested a fish elevator system. This system is simply a mechanically operated "Archimedes Screw" contained within a fiberglass or PVC pipe wherein the fish are lifted from the pond and off-loaded on a truck or tank system. It can have a built-in grader distribution system that sorts fish by size and distributes them to separate holding tanks or hauling trucks. This system minimizes tissue damage, prevents unsightly wounds, abrasions, and/or scale losses that may impact the quality of the fish at market. Handling and processing Hybrid striped bass are marketed and processed in two primary fashions: live market and fresh, whole-fish on ice. There is a growing trend in the Individual Quick Freezing (IQF) flash-frozen, fillet market, but it is secondary to the two primary methods. Regardless, because of the hybrid Morone’s high metabolic rate and susceptibility to handling stress care must be taken to avoid product quality and shelf-life problems. Thus, harvested fish should be handled as gently as possible with minimal physical contact as they will “bruise”

FAO Fisheries and Aquaculture Department easily and develop stress-related reddened areas on the flesh due to petechial hemorrhaging.

If fish are live hauled, particularly in warm weather, they should be placed in a cooled, salt-water system (isosmotic ~7–10 ppt) with pure oxygen supplied to the tank to minimize stress. Live haul trucks typically have 2 500–4 500 kg capacities but density should be considered in proportion to distance to market or processing facility and the amount of ice needed to keep temperatures down and oxygen needed to keep dissolved oxygen at saturation or higher level.

Alternatively, fish can be packed on ice in boxes at the harvest site and loaded onto a refrigerated truck for transport. In this case immediately “chill-killing” the fish at harvest by placing them in an ice brine may be advantageous. First, it quickly calms the fish down and prevents further injury to itself or other fish. Second, it quickly lowers body temperature, which helps maintain ice levels in packing boxes and prolongs the freshness of the fish tissue.

The amount of ice needed for transport is dependent on the initial temperature of the fish, the adequacy of the insulation in the transport unit, and the amount of time the fish need to be on ice. In general, with good fish-ice contact, 0.33 kg of ice will reduce the temperature of a 1 kg fish from 27 oC to 2 oC over a 4-6 hour period. If longer periods of time are needed to keep the fish iced (e.g., 12 h) then a 1:1 ratio of ice to fish weight is recommended. Fresh fish that have been adequately chilled and iced immediately can be held on ice for 8–9 days and still maintain high quality of the flesh. Ideally flesh should be maintained as close to 0 C as possible.

In processing, the fish should be bled as soon as possible. After exsanguination, fish are washed and eviscerated. The head may or may not be retained dependent on market choice (e.g., fish is marketed “in the round”). For fish that are not to be skinned, scaling should be done; even before filleting. The filleting can be done manually or mechanically, but mechanical filleting usually produces a lower yield. With hybrid Morone fillets yields are about 29–50 percent of the whole fish. Other processing yields can be seen in the table below.

Processing yields fromsunshine bass (from Coale et al., 1993) Product Form Percent Yield Whole fish 100 Dressed, with gills 90.5 Dressed, without gills 85.4 Fillet, with rib bones 45.4 Fillet, with skin 41.9 Fillet, without rib bone, skinless 32 Fillet, without rib bone, skinless, trimmed 29.5 Solid waste: Frame 48.8 Skin 19.8 Viscera 9.5 Production costs Fixed costs for production systems are dependent on the production segment(s) with which the producer is involved (e.g., land purchase or water column leases for pond, cage or net-pen, intensive tank culture); water supply (e.g., wells or pumps for surface water systems); loan costs; and permitting requirements listed by the country in which the producer is located and who owns the land and water supply systems. Variable costs include electricity, feed, seed supply (contingent upon production segment), production labour, other labour needs, packaging, processing, distribution, maintenance, supplies, medicines (where available), chemicals, and insurance. In recent years feed has seen the biggest increase in annual costs with shifts as high as 17 percent. The second highest increase in variable costs, at least within the United States, has been crop and liability insurance with annual increases approaching 12 percent. Transportation costs from the farm to the processing

FAO Fisheries and Aquaculture Department facility or market are also a considerable variable cost.

Other limiting factors that need consideration are diseases and approved disease treatment; proper food storage to prevent the establishment of mould or infestation of insects; the presence of fish eating birds and a means to control them; snakes, alligators, and turtles; and back-up generator systems in case of power failures when supplemental oxygenation and/or water flow systems are needed.

Diseases and control measures

Good husbandry techniques can help avoid most hybrid Morone diseases. Many of these diseases are as a response to some external stressor that has made the fish more susceptible to infection with a disease agent. Thus, the key to disease management is stress avoidance.

In some cases antibiotics and other pharmaceuticals have been used in treatment but their inclusion in this table does not imply an FAO recommendation.

DISEASE AGENT TYPE SYNDROME MEASURES Quarantine affected fish to prevent Depending on the virus there may be spread to small, nodular, transparent, lesions on other fish. the fins and skin, which slough off Disinfect Viral Diseases: releasing the virus that can infect other (200 mg/L) Lymphocystis, Iridovirus; fish. Infected fish may exhibit darting with chlorine Infectious Birnavidae family; random swimming behavior with Virus. and dry Pancreatic Aquareovirus sp. or darkened pigmentation. Or, there may rearing Necrosis, striped Aquarotavirus sp. be hemorrhagic lesions of skin along the facilities after bass Aquareovirus. dorso-lateral portions of the body where outbreak. scales are missing. Hemorrhages are also Treat found in the swimbladder and the liver incoming becomes pale and enlarged. water with UV radiation or ozone. Avoid Hemorrhaging lesions and necrosis of stressing the skin, fins, and internal organs, animals in including the brain. Fish will stop or captivity and Freshwater slow down feeding becoming moribund; Aeromonas spp.; maintain good Bacterial Diseases: fins have frayed margins and may be Pseudomonas spp.; water quality Motile Aeromonad white or darker in color; scales may Flavobacterium at proper Septicemia, protrude (lepidorthosis) as a result of spp.; Enteroccocus stocking Columnaris, edema and scale pockets; fluids in or faecium; densities. May Bacterial Gill behind the eyes causes exophthalmia; Edwardsiella Bacteria. be seasonal Disease, gills are often pale and necrotic or may tarda; and related to Entroccocosis, become enlarged; and often bloody fluid Streptococcus optimal Edwarsiella appears in body cavity with numerous iniae; temperature Septicemia, abscesses in kidney that expands to Corynebacerium for growth. Streptococcosis, nearby muscle tissue. May possess a aquaticum. Avoid high Corynebacteriosis. foul odour. Streptococcus iniae may concentrations become a zoonotic, and of organic Corynebacerium aquaticum has been matter in known to infect homothermic animals. water. Avoid FAO Fisheries and Aquaculture Department Avoid Generally found in brackish or marine stressing environments with clinical signs of animals in lethargy, hyperemia of fins and skin captivity and developing into hemorrhagic, ulcerative maintain good lesions on the skin, fins, gill, eyes, and water quality organs. Petechial hemorrhaging may be at proper Estuarine or Marine Vibrio spp.; present at base of fins. Gills are often stocking Bacterial Diseases: Mycobacterium pale and eyes may be hemorrhagic and densities. May Vibriosis, spp.; Bacteria. exophthalmic. Abdominal cavity can be seasonal Mycobacteriosis, Photobacterium become filled with bloody fluid and the and related to Pseudotuberculosis, damsel piscicida. liver appear pale and mottled and be optimal Pasteruellosis. enlarged with white granulomas or temperature military lesions. Spleen is usually for growth. swollen and dark red and kidney is Avoid high swollen and soft – Vibrio and concentrations Mycobacterium disease can be a of organic zoonotic dependent on the species. matter in water. The fungus is most commonly Saprophytic organisms become found in pathogenic when fish are stressed, water injured, or in poor nutritional state. It can temperatures be terminal. Fungal colonies appear as o tufts of cotton on the body and may be above 20 C Saprolegnia white, grey, or turn brown as the that are high parasitica; mycelium trap mud and/or silt. It does in organic Fungal Diseases: Aphanomyces sp.; not usually produce large deep lesions in content. Saprolegniosis, Gill Fungus. Achlya sp.; the muscle. Iinfected fish swim Control is Rot. Branchiomyces lethargically and may linger in a difficult so the sanquinis. moribund state for days before death. best approach Gill Rot grows within the branchial is through blood vessels, but hyphae may protrude husbandry. from necrotic tissues. Gills become Formalin may necrotic and hyperplastic. Saprolegniosis be used on can be devastating on developing eggs. eggs at about 600 mg/L for 15 minute flush. Introduced by carrier fish or the free living stage coming from natural Velvet Disease is a primarily brackish or water marine that infects larvae, fry, and supplies. fingerlings held at high densities. Lower Clinical signs are visible white spots on densities and fin and skin. Fish will congregate at the maintain good surface "gasping for air" or the sink to water quality. the bottom and lose equilibrium. Heavy Rarely a Parasites: infestations lead to gill necrosis and may problem in Flagellated result in 80% mortality. Icthyobodiasis is open-water Amyloodinium FAO Fisheries and Aquaculture Department Amyloodinium Protozoans Velvet Protozoan present on gills and skin and is a tear- cages, net- ocellatum; Disease or Flagellates. shaped flagellate about the size of a red pens or flow- Ichthyobodo sp. Amyloodiniasis; blood cell with a pair of flagella, one of through Icthyobodiasis. which modifies to attach to the gills or systems skin. Both organisms are obligate because parasites and infected fish go off feed parasite and become lethargic with heavy cannot mucous development. Young fish are complete life more susceptible. Infected fish also cycle. Avoid flash, "scratching" their sides on the tank stressing the walls. animals and maintain good water quality, nutrition, and stocking densities. Whitespot disease is the most devastating protozoan found in fish and can cause high mortality rates. An obligate parasite they typically become embedded in the epithelium where they form characteristic white spots (trophozoites), which is a clinical sign. Low to moderate infestations often lead to heavy infestations that can cause devastating mortalities particularly in intensive culture systems. Chilodonella Icthyophthirius Avoid Parasites: are flat, spoon-shaped, motile multifiliis stressing the Ciliated Protozoans protozoans approximately 30- (freshwater) and animals and Ichyopthiriasis or 70 microns in size, and are found on Cryptocaryon Protozoan maintain good Whitespot Disease; gills or skin. Epistylis infects skin, fins, irritans (saltwater); Ciliates. water quality, Slime Disease; and gills and is an urn-shaped organisms Chilodonella spp.; nutrition and Epistylis; with a ring of cilia on the distal end. The Epistylis spp.; stocking Trichodinosis. organism by a disk to spines, scales, or Trichodina sp. densities. opercula. The parasite causes irritations and inflammation of the epithelium at the point or attachment and will eventually erode scales or spines. Trichodina are round and saucer or bell shaped with a ring of cilia on the margins. They move over the surface like a saucer and found in low numbers on gills, fins, or skin of most fish but can become very numerous and extremely injurious. No approved treatment, but external infections of monogenetic trematodes can be Occur on the gills, skin, and fins where removed by

FAO Fisheries and Aquaculture Department they browse on dermal or gill debris. 15-25 mg/L Attach to the host by the haptor, a hook- formalin in like or sucker-like valve that can cause ponds or Diplectanum sp.; Metazoan - epithelia damage. Often the density of 167 mg/L in a Parasites: Gyrodactylus sp.; Monogenetic these flukes can become large enough to flow-through Gill Flukes. Microcotyle sp.; Trematodes. cause host tissue damage. Infected fish or Urocleidus sp. become lethargic, swimming near the recirculating surface and going off-feed. Death is tank (make infrequent. Gills may be hyperplasic and sure you do necrotic with heavy mucous production. not sent the treated water through biofilters and watch dissolved oxygen levels). Yellow grub infested fish have visible 1- Best control 2 mm yellow cysts in the muscle. When for digenetic large are present the fish appearance is trematodes is unsightly and may prevent marketability. breaking the White grubs infests the heart, liver, life cycle of spleen, kidney, and muscle of fish. the parasite by Encysted larvae appear as small white Clinostomum eliminating spots and may be numerous. If present complanatum; C. snails and behind the eye they can cause Parasites: marginatum; blocking exophthalmia. Infestations can lead to Yellow and White Posthodiplostomum Metazoan - access of fish hemorrhaging, severe edema of the Grubs; Black Spot minimum; Uvulifer Digenetic eating birds to musculature and very pale internal Disease; Eye sp.; Neasus sp. Trematodes. culture ponds organs. Black spot disease is so named Flukes . Diplstomum or tanks. because the grub infects the skin and flexicaudum; D. Avoid flesh of the hosts. If densities are high spathaceum. stressing the they can make the fish unmarketable animals and unless the skin is removed completely, maintain good which will remove the grub as they are water quality, primarily superficial. Eye flukes infest nutrition and the eyes where the larval concentration stocking causes the eye lens form (cataracts) densities. leading to blindness. Cestodes live in the intestine of piscivorous fish, where the larval stages infect the visceral organs. Fish are intermediate hosts. They are unsightly and cause concern for the consumer. Nematodes infect the visceral organs or Best control the larvae encysts in the eye. May be in for tape the messentaries where the blood-red worms is Parasites: worm resembles blood vessels. Cause Tapeworms; breaking the Tapeworms – little harm unless it infects the eye Philometra sp.; life cycle of Cestodes; wherein the eye can be destroyed. Cucullanis sp.; the parasite by Roundworms – Metazoan – Goezia is primarily found in marine fish Goezia sp.; eliminating Nematodes; Worms. and can be problematic if raw infected Spinitectus sp.; snails and Spinyhead Worms fish are fed directly to Morone in grow- Pomphorhynchus blocking FAO Fisheries and Aquaculture Department Pomphorhynchus blocking – out situations. Spinyhead worms possess laeve. access of fish Acanthocephalans. an anterior proboscis covered with many eating birds to hooks with which they attach to the culture ponds epithelium of the intestines. Where the or tanks. proboscis is embedded in the epithelium of the host’s gastrointestinal tract there may be necrosis, ulceration, and peritonitis. If infections are heavy death may occur. Encysted larvae are found in the viscera of Morone. Use of These blood-sucking annelid worms are Masoten transient and usually cause no health (Dylox) for Parasite: Leeches. Annelids. problem unless the fish are small 0.5-1.0 mg/L Leech. wherein large infestations can be for a one hour problematic. bath. Destroy leech habitat. Avoid Female Lernaea attach to the skin where stressing the their modified head is imbedded into the animals and flesh. They develop two egg sacs at the maintain good distal end. After hatch, they migrate to water quality, the gills. After molting through several nutrition and stages they mate (after which the male stocking dies) and the females move back to the densities. flesh of the fish where the cycle starts Increase water again. The gill stages however can cause flow in Parasite: extensive injury to gill filaments. intensive Crustaceans Lernaea spp.; Ergasilus attach to the gills of fish and culture Anchor Worms; Ergasilus spp.; Crustaceans. follows a similar life pattern as Lernaea, facilities to Gill Maggots Fish Argulus spp. but they are smaller and not visible flush out free- Lice. without microscopy. They can damage swimming the gill epithelia causing gill hyperplasia stages. and necrosis. Argulus is a large parasite Masoten that moves and feeds freely on the skin, (Dylox) fins, and gills. The parasite leaves the treatment at host to lay eggs on vegetation and at 0.25 mg/L in hatch the napuli free-swim to find a new ponds may host. Unless large numbers exist they help control cause little damage but they are crustacean unsightly. parasites. Note:

1. For all measures no chemicals can be used in the United States for control of infectious diseased fish for human consumption. Thus, health maintenance, disease prevention, quarantine, and maintaining husbandry practices with good water quality is essential to good fish health. 2. In all cases with bacterial infections avoid stressing animals in captivity and maintain good water quality at proper stocking densities. Disinfecting water in recirculating systems with UV or Ozone helps. In freshwater systems prophylactic treatments with Na Cl (0.5-2 percent) or Potassium Permanganate (2-5 ppm) for differing periods of time may be helpful. Check to see which medicated feeds and/or vaccinations are allowed for systemic infections. 3. Because protozoans are ubiquitous and are most problematic during stressful conditions such as handling or poor water quality, utilization of best management practices in husbandry and water quality FAO Fisheries and Aquaculture Department management is important. Insure good water quality, moderate stocking densities, good nutrition, and proper handling will mitigate the probability of protozoan infections.

Suppliers of pathology expertise

Most federal, provincial, and state agencies responsible for managing the natural resource of the country of interest will have some disease-diagnostic services. In academia, most veterinary colleges and universities will be a source of assistance. There are limited numbers of private practices that deal with fish diseases so it is important to work with the state or provincial licensing authorities to locate a certified disease specialist.

Within the United States primary contacts would be through the U.S. Department of Agriculture Animal Health and Plant Inspection Service and their regional Fisheries Research Centers; the U.S. Department of Interior Fish and Wildlife Service and the U.S. Geological Survey fishery research units; and the Department of Commerce National Oceanic and Atmospheric Administration Aquaculture Division. Statistics Production statistics

Global Aquaculture Production for species (tonnes) Source: FAO FishStat 7.5k

5k

2.5k

0k 1950 1960 1970 1980 1990 2000 2010

Morone chrysops x M. saxatilis

Market and trade

In the United States, 2014 pricing of hybrid Morone for live fish was USD 4.37/kg, which was down from 2013 FOB (Free On Board) prices of USD 4.43/kg. In contrast whole fish on ice in 2013 brought an average retail price of USD 3.60/kg while it increased in 2014 to USD 5.25/kg. Overall in the United States FOB pricing for whole fish (on ice) had increased 2.4 percent/year since 1996.

In 2014 the United States, industry total farm-gate market segment exceeded USD 33.2 million. Individual farm-gate market segment values were as follows: On-ice (whole) – USD 21.9 million; Live – USD 8.7 million; Seed stock – USD 323.5 thousand; Nursery fingerlings – USD 6.8 thousand. Thus, the largest market share value-wise is with whole fish in the round on ice. On a global basis there was a significant jump in market value that exceeded USD 50 million while previously the highest global value was around USD 37 million. Status and trends With the exception of 2013, hybrid Morone culture production has seen a decline to steady rate production in

FAO Fisheries and Aquaculture Department the past decade, but production in Europe and Asia is expected to continue into the near future as more domesticated broodstock are developed, and they become less dependent on United States seed suppliers. Within the United States the per capita consumption of cultured seafood is expected to reach 55 percent in 2015 and projected to grow. Hybrid Morone is able to compete well with other marine species and within the United States its largest competitor is the striped bass from wild-caught fisheries, which is seasonal and imports of marine species such as European seabass (Dicentrarchus labrax) and spotted seabass (D. punctatus), barramundi (Lates calcarifer) and other Lates spp., Patagonian toothfish (Dissostichus eleginoides), and fish such as common dolphinfish (Coryphaena hippurus). There appears to be strong pricing growth expectations; especially as hybrid Morone begin to be exported more to Europe and Southeast Asia. Overall on a global basis there is an expectation in production growth and competitive pricing. European and Asian production appears to be all consumed locally with little to no export. There is limited export of hybrid Morone of market- sized fish.

With regard to needed areas of research the six identified priority areas by the hybrid Morone industry are as follows: 1) understand and improve the nutritional needs of the different hybrid and parents being cultured; 2) improved survival and growth of larval fish; especially in indoor tank systems; 3) improvements in controlled reproduction; 4) better understanding of genetic variability across natural geographical ranges of broodstock; 5) detailed information on parental strains; and, 6) development of DNA markers and genetic maps that affords better selection efforts (to date over 500 microsatellite markers have been identified).

Strain evaluations of parental crosses are still on-going at several United States academic institutions. There are on-going efforts in the United States to domesticate a marine strain of striped bass that will be more suited to off-shore net-pen operations that, when successful, will be a year-round competitor for hybrid Morone production capacity.

Within the United States there is little effort to domesticate white bass males or females because they are so readily able to be captured as gravid and running-ripe individuals from the wild. Some effort is ongoing to domesticate both striped bass and white bass in Europe and Asia. Hormonal maturation and ovulation control research is still on-going but current technology, along with photoperiod-thermal manipulation to extend spawning seasons and provide out-of-season spawning, appear to be adequate.

Diet and nutrition research are critical to continued success and improvement in the industry. It appears proper balance of the dietary amino acid profiles, supplements with high omega-3 fatty acid, and substitutes for fish meal and oils are high priorities. Research with striped bass diets has demonstrated squid substitutes for fish meal and oils up to 25 percent is successful. Some efforts have been undertaken to genetically select for white bass that produce a larger mouth gape to remove the need for the rotifer batch culture approach and increase opportunities to fully close the life cycle of broodstock to indoor systems.

Male gamete storage has become more successful with both cold-banking and long-term cryopreservation. This fact will aid in the growth of the hybrid industry because often it is difficult to synchronize spawning of the two parents required to produce hybrids due to slight temporal spawning differences between species. Having cryopreserved semen alleviates that concern.

From an economic perspective sustained growth will be dependent on improved success of closed, high- density production systems, improved access and affordability to and of crop insurance to protect against catastrophic losses, and reasonable access to both public and private funding as incentives for construction and reasonable consideration to loan repayments. Main issues The main concerns associated with hybrid Morone culture are similar to those of any predatory fish species. These include ecological, environmental, and genetic. From an ecological perspective because hybrid Morone can disrupt the natural ecology if they escape into the environment, especially outside of their natural range.

FAO Fisheries and Aquaculture Department Environmental concerns relate to use of antibiotics, waste discharges, and processing by-products. The use of antibiotics and some prophylactic chemicals to treat the water source can release non-metabolized antibiotics into the environment raising the concern of antibiotic resistant strains of bacteria. Likewise, there are concerns about the potential of bioaccumulation of prophylactic chemicals in sediments and other areas associated with aquaculture site locations. Similarly, because the diets are high in protein and fish digestibility levels generally are inefficient, there is a constant concern of organic waste and nitrogen and phosphorous build-up in effluents or underneath open-water net pens or cages. Processing waste disposal is another important environmental consideration. Most operations are constantly looking for waste utilization options and some innovative approaches are now being tested.

Last are genetic concerns. Hybrid Morone are not sterile and several generations and backcrosses have been found under both artificial production settings and in natural environments where hybrids have been stocked with sympatric parental species. Thus, while not common, backcrosses and putative F2s have been collected from the spawning grounds of other Morone. So the potential of outcrossing with pure parents is real and should be considered before large-scale operations are put into place – precautions in design and redundancy to prevent escape are therefore important.

Recognition of the risks associated with any form of aquaculture should be integral to any planning and development considerations. Precautionary steps, if appropriately taken, should mitigate any major concern responsible agencies may have in permitting and approving aquaculture operations regardless of the target species being considered. Responsible aquaculture practices

Aquaculture is a growing global food production sector and has strong links to natural resource management and concerns for environmental protection. Because hybrid Morone are a vertebrate and their culture is usually in concentrated intensive husbandry conditions there are growing concerns for animal welfare. Production operations should proactively take steps to minimize any undue stress to the animals and minimize what might be perceived as animal cruelty. Such considerations as hunger, discomfort, pain, injury, or disease are all listed in the arena of animal cruelty. This concern is especially prevalent in Europe and is growing annually within the United States Therefore, ethical production of all phases of the aquaculture operation is important. Proper steps taken to ensure animal welfare can also be an excellent marketing tool and aquaculture associations that police themselves and certify that operations take critical steps to ensure animal welfare may well be a branding opportunity that adds value to the final product.

Certain market segments such as European countries will not accept genetically modified organism. Thus, as research continues to move forward we must find other means to improve performance and examine ways to produce fish that grow faster, are more disease resistant, and have better food conversion ratios. At the moment interspecific hybrids are not shunned by consumers, but there are regulatory issues that must be considered and permission to produce procured before operations are initiated. References Bibliography

Blazer, Vicki S., and S.E. LaPatra. 2002. Pathogens of culture fishes: Potential risks to wild fish populations. Pages 197-224, In J.R. Tomasso, Editor. Aquaculture and the Environment in the US. U.S. Aquaculture Society, A Chapter of the World Aquaculture Society, Baton Rouge, Louisiana, USA. Coale, C.W., J.P. Anthony, G.J. Flick, G.S. Libey, G.-P. Hong, G.D. Spittle, and N.A. Valley. 1993. Marketing aquaculture products: A retail market case study for sunshine bass. Virginia Aquaculture Experiment Station Bulletin 93-3, Virginia Polytechnical and State University, Blacksburg, Virginia, USA. D’Abramo, L.R. and M.O. Frinsko. 2008. Hybrid striped bass: Pond production of food fish. Southern Regional Aquaculture Center, SRAC Publication Number 303, Mississippi State University, Stoneville, Mississippi, USA.

FAO Fisheries and Aquaculture Department FAO 2014. Striped bass and hybrid striped bass production. FAO - Fisheries and Aquaculture Information and Statistics Service. Gupta, M.V., and B.O. Acosta, Editors. 2001. Fish genetics research in member countries and institutions of the International Network on Genetics in Aquaculture. ICLARM Conference Proceedings 64, 179 pp. Harrell, R.M., Editor, 1997. Striped bass and Other Morone Culture. Elsevier Science, Oxford, England. Harrell, R.M. 1997. Morone pond production. Pages 75-97, In R.M. Harrell, Editor, striped bass and Other Morone Culture. Elsevier Science, Oxford, England. Harrell, R.M. 2002. Genetic implications of escaped and intentionally-stocked cultured fishes. Pages 167-196, In J.R. Tomasso, Editor. Aquaculture and the Environment in the US. U.S. Aquaculture Society, A Chapter of the World Aquaculture Society, Baton Rouge, Louisiana, USA. Harrell, R.M. 2013. Releasing hybrid Morone in natural waters with congeneric species: Implications and ethics. Pages 531-549, In J.S. Bulak, C.C. Coutant, and J.A. Rice, Editors. Biology and Management of Inland striped bass and Hybrid striped bass. American Fisheries Society Symposium 80. America Fisheries Society, Bethesda, Maryland, USA. Harrell, R.M., J.H. Kerby, and R.V. Minton, Editors. 1990. Culture and Propagation of striped bass and its Hybrids. Striped bass Committee, Southern Division, American Fisheries Society, Bethesda, Maryland, USA. Harrell, R.M., and J.M. Dean. 1988. Identification of juvenile hybrids of Morone based on meristics and morphometrics. Transactions of the American Fisheries Society 117:529-535. Halbrendt, C.K, R.Aull-Hyde, and D.W. Dunkers. 1994. Expert opinions on critical production factors for sustained growth of the hybrid striped bass industry. Transactions of the American Fisheries Society 123:94- 100 Hochheimer, J.N., and F.W. Wheaton. 1997. Intensive Culture of Striped bass. Pages 127-168, In R.M. Harrell, Editor, striped bass and Other Morone Culture. Elsevier Science, Oxford, England. Hughes, J.S., T.L. Wellborn, and A.J. Mitchell. 1990. Parasites and diseases of striped bass and hybrids. Pages 217-238, In R.M. Harrell, J.H. Kerby, and R.V. Minton, Editors. Culture and Propagation of striped bass and its Hybrids. Striped bass Committee, Southern Division, American Fisheries Society, Bethesda, Maryland, USA. Jenkins, R.E., and N.M. Burkhead. 1994. Freshwater Fishes of Virginia. American Fisheries Society: Bethesda, Maryland, USA. Kelly, A.M. 2015. U.S. Hybrid striped bass Industry Update (presentation, Aquaculture America ’15, New Orleans, Louisiana, USA, Feb 19-22, 2015). Kohler, C.C. 1997. White bass production and broodstock development. Pages 169-184, In R.M. Harrell, Editor, striped bass and Other Morone Culture. Elsevier Science, Oxford, England. Lougheed, M., and B. Nelson. ND. Hybrid striped bass production, markets and marketing. North Central Regional Aquaculture Center Publication, Michigan State University, East Lansing, Michigan, U.S.A. Ludwig, G.M. 2004. Hybrid striped bass: Fingerling production in ponds. Southern Regional Aquaculture Center, SRAC Publication Number 302, Mississippi State University, Stoneville, Mississippi, USA. McGinty, A.S., and R.G. Hodson. 2008. Hybrid striped bass: Hatchery phase. Southern Regional Aquaculture Center, SRAC Publication Number 301, Mississippi State University, Stoneville, Mississippi, USA. Mullis, A.W., and J.M. Smith. 1990. Design considerations for striped bass and striped bass hybrid hatching facilities. Pages 7-27, In R.M. Harrell, J.H. Kerby, and R.V. Minton, Editors. Culture and Propagation of striped bass and its Hybrids. Striped bass Committee, Southern Division, American Fisheries Society, Bethesda, Maryland, USA. Plumb, J.A. 1997. Infectious disease of striped bass. Pages 271-313, In R.M. Harrell, Editor, striped bass and

FAO Fisheries and Aquaculture Department Other Morone Culture. Elsevier Science, Oxford, England. Rawles, D.D., C.F. Fernandes, G.J. Flick, and G.R. Ammerman. 1997. Processing and food safety. Pages 329-356, In R.M. Harrell, Editor, striped bass and Other Morone Culture. Elsevier Science, Oxford, England. Small, B.C., and L. Curry Woods, III. 2013. Current state and prospects for hybrid striped bass production in the US. Powerpoint Presentation made at the 2013 China-US Forum on the Innovation for Mandarin-Fish and Bass-Perch production and personal communication. Southern Illinois University, Carbondale, Illinois, USA. Smith, S.A., and D. Pasnick. 2010. Common diseases of cultured striped bass, Morone saxatilis, and its hybrid (M. saxitilis [sic] x M. chrysops). Virginia Cooperative Extension Publication 600-800, Blacksburg, Virginia, USA. Smith, T.I.J., W.E. Jenkins, J.M. Whetstone, and A.D. Stokes. 1990. A Guide to Pond Culture of Hybrid striped bass. South Carolina Sea Grant Extension Program. South Carolina Sea Grant Consortium, Charleston, South Carolina. Sullivan, C.V., D.L. Berlinsky, and R.G. Hodson. 1997. Reproduction. Pages 11-73, In R.M. Harrell, Editor, striped bass and Other Morone Culture. Elsevier Science, Oxford, England. Tomasso, J.R. 1997. Environmental requirements and noninfectious diseases. Pages 253-270, In R.M. Harrell, Editor, striped bass and Other Morone Culture. Elsevier Science, Oxford, England. Related links

Aquafind Aquatic Network Database on Introductions of Aquatic Species - DIAS European Aquaculture Society - EAS FishBase FAO FishStatJ – Universal software for fishery statistical time series GLOBEFISH Network of Aquaculture Centres in Asia-Pacific - NACA World Aquaculture Society - WAS

FAO Fisheries and Aquaculture Department