Striped Bass - Tange & Habitat
The striped bass (Morone saxatilis) is found in coastal waters along the North American Atlantic coast, from St. Lawrence River, Canada to St. Johns River, Florida, USA, although this species is most prevalent from Maine to North Carolina. In addition to coastal waters, striped bass is also found in rivers and lakes. The striped bass is a migratory fish that travels from saltwater to freshwater to spawn, but landlocked population do exist.
In the ocean, striped bass is normally not encountered more than 10 km offshore. The fish typically move north to nearshore waters of the New England coast during the summer, and south to the North Carolina/Virginia Capes during the winter.
The east coast populations are composed of three major stocks: Hudson, Chesapeake and Roanoke. There are also landlocked populations.
The striped bass is a popular game fish and has been introduced by man to many parts of the world, including plenty of areas of the United States outside its native range. As early as 1879 and 1882, striped bass was transported from the Navesink River in New Jersey to California's San Joaquin River Delta, and the striped bass is today well established in San Francisco Bay and along the Oregon coast.
Other parts of the world where striped bass can be found due to human introduction are South Africa, Turkey, Iran, Latvia, Mexico and Ecuador.
Stripped bass inhabit coastal waters up to 10 kilometers from shore and are often found in bays. In spring, they migrate to freshwater rivers and lakes to spawn. There are also landlocked populations that populations of striped bass that live, grow and reproduce in freshwater and never migrates to the sea.
Striped bass can live in both saltwater and freshwater, and the range of this fish is therefore limited chiefly by other factors than salinity. Such limiting factors can for instance be temperature, oxygen content and access to food. In some habitats, the conditions are only suitable during part of the year and the striped bass is therefore forced to move on a regular basis.
Landlocked populations of striped bass can not move if conditions changes and they are therefore only found in habitats where conditions are sufficiently good year round.
The main reason why striped bass move to the ocean from the freshwater habitat in which they hatch is believed to be access to food. The ocean provides the striped bass with larger feeding grounds and can support a larger population than what would be possible in a lake or stream.
Essential fish habitat (EFH) and the law
In the United States, essential fish habitat (EFH) is protected by law under the Magnuson Stevens Act, passed by US Congress in 1996. Essential fish habitat includes all types of habitat where fish spawn, breed, feed or grow to maturity.
In order to best protect essential fish habitat for striped bass, we need to understand more about where this fish spend their time – during the day, during the night and throughout the year. It is also important to know why certain locales are sought out when they are. In the Stripped Bass Project, the researchers are not only trying to find out how the fish moves; they also want to understand why it moves (or does not move) between different habitats.
Researching a habitat
The scientists involved in the Striped Bass Project do not only track fish; they investigate the environment as well in order to pin down factors that attract striped bass to certain habitats during certain parts of the year.
Scientists in the Jacques Cousteau National Estuarine Research Reserve (JCNERR) currently use series of methods to investigate this habitat. They have a REMUS (Remote Environment Monitoring UnitS) vehicle that maps water currents and measures salinity, temperature, fluorescence and pH-value. This torpedo-shaped submarine is also fitted with a side scan sonar that creates a 3D-picture of the underwater world.
Other examples of factors that may be relevant for the striped bass are light levels, oxygen content and wave height.