Glossary 



ABYSSAL ZONE— Ocean bottom at depths between 

 4,000 and 6,000 m. 



AQUACULTURE— The rearing of aquatic (marine or 

 freshwater) vertebrates, invertebrates, or algae, to be 

 harvested for commercial or subsistence purposes. 

 See MARICULTURE. 



ABYSSOPELAGIC— Living in the water column at 

 depths between 4,000 and 6,000 m; the abyssopelagic 

 zone. 



ADDUCTOR MUSCLE— A muscle that pulls a part of 

 the body toward the median axis of the body. In bivalve 

 molluscs, this muscle is used to close the shell halves 

 and hold them together. 



ADHESIVE — Sticky and tending to adhere; e.g., adhe- 

 sive eggs. 



AGE-GROUP — A term used to designate year-classes 

 in fishes; a division date of January 1 is used in the 

 northern hemisphere. See YOUNG-OF-YEAR, YEAR- 

 LING, and TWO-YEAR-OLD. 



AGGREGATION — A group of individuals of the same 

 species gathered in the same place but not socially 

 organized or engaged in cooperative behavior. Com- 

 pare to SCHOOL. 



ALGAE — A collective, or general name, applied to a 

 number of primarily aquatic, photosynthetic groups 

 (taxa) of plants and plant-like protists. They range in 

 size from single cells to large, multicellular forms like 

 the giant kelps. They are the food base for almost all 

 marine animals. Important taxa are the dinoflagellates 

 (division Pyrrophyta), diatoms (div. Chrysophyta), green 

 algae (div. Chlorophyta), brown algae (div. 

 Phaeophyta), and red algae (div. Rhodophyta). 

 Cyanobacteria are often called blue-green algae, al- 

 though blue-green bacteria is a preferable term. 



AMBICOASTAL — Used in reference to enclosed bay 

 systems to denote both estuarine and marine coasts. 



AMPHIPODA— An order of laterally compressed crus- 

 taceans with thoracic gills, no carapace, and similar 

 body segments. Although most are <1 cm long, they 

 are an important component of zooplankton and benthic 

 invertebrate communities. A few species are parasitic. 



ANADROMOUS — Life cycle where an organism spends 

 most of its life in the sea, and migrates to fresh water to 

 spawn. Compare to CATADROMOUS. 



ANNULUS — Annual growth mark on a scale, bone 

 (e.g., otolith), or other hard structure. 



ANTHROPOGENIC— Refers to the effects of human 

 activities. 



AREAL — Refers to a measure of area. 



ASCIDIAN — A tunicate (class Ascidiacea) that has a 

 generalized sac-like, cellulose body and is usually 

 attached to the substratum. 



AUTOTROPH — An organism using sunlight or inor- 

 ganic chemical reactions as a source of energy to 

 synthesize organic matter. Compare with 

 PHOTOTROPH and HETEROTROPH. 



BATCH SPAWN — Discontinuous episodes of spawn- 

 ing, either of gametes or offspring. Individuals or 

 populations that release gametes or offspring with 

 greater continuity are serial or sequential spawners. 



BATHYAL— The zone of ocean bottom at depths of 

 200 to 4,000 m, primarily on the continental slope and 

 rise. 



BATHYMETRIC— Pertaining to depth measurement. 

 Also refers to a migration from waters of one depth to 

 another. 



BATHYPELAGIC— Ocean depths from 1,000 to 4,000 

 m. 



BENTHIC— Pertaining to the bottom of an ocean, lake, 

 or river. Also refers to sessile and crawling animals 

 which reside in or on the bottom. 



BIGHT— An inward bend or bow in the coastline. 



BIOMASS— The total mass of living tissues (wet or 

 dried) of an organism or collection of organisms of a 

 species ortrophic level, from a defined area or volume. 



BIVALVIA— Bilaterally symmetrical molluscs (also re- 

 ferred to as Pelecypoda) that have two lateral calcare- 

 ous shells (valves) connected by a hinge ligament. 

 They are mostly sedentary filter feeders. This class 

 includes clams, oysters, scallops, and mussels. 



BRANCHIAL — A structure or location on an organism 

 associated with the gills. 



BROADCAST SPAWNER— Planktonicreleaseof float- 

 ing or sinking (demersal) gametes (eggs, sperm) or of 

 offspring. May be continuous or periodic in duration. 

 See BATCH SPAWN. 



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