Hybrid striped bass do not occur naturally in the wild. Thus their distribution in the environment is solely the result of stocking programs and rare escapees from culture ponds. The distribution of this hybrid is primarily to the Mississippi drainage where the white bass is native. The distribution of the broodstock for these fish, the striped bass (Morone saxatilis) and the white bass (Morone chrysops) are however well documented. The striped bass is an anadromous fish native to the North American Atlantic Coast from New Brunswick to Florida and along the Gulf Coast from Florida to Texas. This prized game fish has since been introduced to the Pacific Coast and populations are bountiful from British Columbia to Mexico. Landlocked striped bass in North American fresh water systems are also present. The white bass was originally distributed in the Mississippi basin and along the Gulf coast, but has since been introduced throughout the United Stated. Hybrids are also located in Israel were intensive culture is practiced.

HABITS:

These hybrids are stocked into a variety of aquatic systems including large reservoirs, slow moving streams, lakes and ponds and are usually located in the deeper pelagic zone of these systems. Seldom are they found in the littoral zone. They also tend to be crespuscular piscines feeding most actively at daybreak and nightfall. Seasonal migrations are often observed with these fish. During late winter they tend to congregate in deep areas associated with in flowing stream water. They migrate upstream during the spring to spawn.

SPAWNING:

Spawning runs of hybrid bass have been observed and successful spawnings reported. This is rather unusual because most hybrid species are infertile. Both male and female hybrid striped bass (250mm in length) are ready to spawn in the spring when water temperatures reach 15-20C. These fish are generally 2 years old, but may be as young as a year in age. Spawning in natural systems occurs over a five-week period in areas containing clear rocky shoals in water approximately 1-3 feet in depth. Males may spawn several times over the spawning season. The production of hybrid striped bass is probably of greater interest however. There are a few different "crosses" of hybrid striped bass. The "original cross" or Palmetto bass (female striped bass x male white bass) was first achieved in South Carolina during the late 1960’s. Since then the "reciprocal cross" or Sunshine bass (female white bass x male striped bass) and is desired by culturists due to the larger gape of the offspring during the early life stages. Like the hybrid offspring the parental species are both oviparous fishes. Eggs of striped bass are buoyant while the white bass eggs are heavy and adhesive. As previously mentioned these fish do not naturally spawn in the wild; therefor, propagation of offspring is accomplished by culturists using hormone injections of human chorionic gonaotropin (HCG) and strip spawning techniques. Optimal temperatures are the same for as those mentioned for the hybrids and the photo period is also often manipulated to mimic that of a typical spring if broodstock are spawned indoors or out of season. Eggs are cultured in jars and hatch about 2 days post fertilization in 65-68F water. Fry feed endogenously for approximately 5 days before reaching the swim up stage at which time they feed on phytoplankton and later zooplankton.

GROWTH:

Optimal water temperatures for hybrid striped bass growth are between 25 and 27F, and rapid growth is generally observed during the first 2 years of life (550 mm in length and 1.5kg by year two). The maximum recorded weight of a hybrid is about 10kg far less than the parental striped bass, and a typical life span of the hybrids is 5 to 6 years. Water quality, temperature, frequency of feeding, and both quantity and quality of food greatly effect the growth of these fish.

USES:

Hybrids striped bass are stocked into natural aquatic systems for recreational anglers. They are a well sought after game fish. Additionally, these fish are of great economic value in the seafood market.

CULTURE:

Hybrid striped bass are cultured in a variety of culture systems across the globe. The most lucrative and productive fingerling producers are located in Arkansas, United States and Israel. Fingerlings are also produced in California, United States. Pond grow out facilities are unquestionably more profitable, but the high economic value of this species has led to interest in producing it in land-based closed-loop systems.

REFERENCES:

Bardach, J.E, J. H. Ryther, and W.O. McLarney. 1972. Aquaculture The farming and husbandry of freshwater and marine organisms. John Wiley and Sons, New York.

Hodson, R.G. Hybrid striped bass biology and life history. SRAC publication no. 300. Arkansas cooperative extension service fact sheet 9045.

Iverson E.S. and K. K. Hale. 1992. Aquaculture sourcebook a guide to north american species. Van Norstrand Reinhold, New York.