Boreal Organisms
Boreal Organisms
marine organisms which inhabit the temperate region of the northern hemisphere.
The greatest abundance of boreal organisms is confined to the coastal zones (littoral and sublittoral). The deepest waters (the bathyal), as in other parts of the world’s ocean, are poor in life because of the constant low temperature and the lack of light. The littoral and sublittoral abound in brown and red algae, among which the most common are the fucoids, laminaria, and ahnfeltia. Particularly common among the mol-lusks are mussels, oysters, and scallops, as are shrimp and crabs among the crustaceans. The standing crop (biomass) of these organisms is very great.
Certain boreal organisms are distinguished by very high biological productivity. For example, with artificial breeding of oysters, it is possible to obtain up to 8 tons of meat per year from 1 hectare of coastal beds. The herring, cod, mackerel, salmon, tuna, flounder, and bass are fish of the greatest commercial importance. The world catch of these fishes in the boreal region is nearly 30 million tons per year. Aquatic mammals such as the cetaceans (basic game in the antarctic) and pinnipeds are of lesser significance among the boreal organisms. The limited nature of cetacean resources is to be explained by overhunting as well as by their low fecundity. (Whales produce only one offspring.)
Plankton is very abundant among the boreal organisms. Plankton production in the world ocean is around 360 billion tons per year, and of this a significant portion consists of the boreal organisms. Attempts have been made to acclimate boreal organisms in new regions in order to increase the animal and plant resources. Examples are the acclimation of the mullet in the Caspian Sea, the Baltic herring in the Aral Sea, and the Far Eastern pink salmon in the Barents and White seas.
REFERENCES
Zenkevich, L. A. Biologiia morey SSSR. Moscow, 1963.Mikhailov, S. V. Ekonomika Mirovogo okeana. Moscow, 1966.
V. A. SVESHNIKOV