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. GLOSSARY OF TERMS Augmentation Stock - Those fish which are released for the purpose of increasing the existing fish population. Biomass - The pounds of fish which are either maintained or produced at the recovery facility. The capacity of the facility to hold and grow fish is expressed in terms of pounds of fish or total biomass. Broodstock - Fish of a particular species, represented by both sexes which are held in captivity until and during maturity for the distinct purpose of crossbreeding. The genetic history is usually known for these animals and they are usually bred according to strict protocols designed to maintain a level of genetic diversity in the progeny. For the purposes of this facility, refugia and broodstock populations are considered the same. Culture Techniques - Different methodologies which are used to hatch and produce fish. For this report, the two categories of culture techniques are intensive culture and extensive culture. . Extensive Culture - A culture methodology which emphasizes more natural rearing conditions for fish that are reared in an artificial environment. Under extensive culture conditions fish are reared at low density in outdoor ponds. Rearing is conducted at ambient temperatures and natural feed items are encouraged to grow in the pond environment. This strategy is employed to alleviate hatchery induced pressures which may work selectively on the genetic diversity of the fish being cultured. This method requires less water and more land than intensive culture. Intensive Culture. A culture methodology designed to achieve maximum productivity for fish held in artificial culture environments. The fish are held at higher densities in tanks or raceways and fed an artificial diet. Rearing temperatures are held at values which are known to achieve maximum growth rates. Water flow rate are high to maintain water quality by carrying away waste products, and excess feed. The primary goal of intensive culture is to achieve maximum fish production levels for a given rearing space while maintaining healthy stocks of fish. Refugia - Individual fish representing genetically distinct stocks of a particular species held in captive habitat. Usually held in reselVe for use as future broodstock and to provide an environment for protection and survival of declining number of endangered fish in the wild. The purpose is to maintain the genetic diversity of a species by maintaining representative examples of distinct, genetically diverse strains from specific native habitats. . 23