GLOSSARY
Welcome to the Fisheries and Oceans Glossary for Aquaculture terms. Terms are grouped alphabetically and are researchable by clicking the corresponding letter of the desired term.
| A | B
| C | D
| E | F
| J
| L
| M | P |
R | S
| T | V | W
| Y
|
A
Adaptability: The ability of an organism to adapt to changing environmental conditions.
Age-class: The brood year (year the fish was born) or the salt-water entry year that defines a cohort of fish (same as year class).
Anadromous - Fish species that return to their spawning rivers from the ocean at certain seasons to breed in fresh water.
Aquaculture: The farming of fish, shellfish and aquatic plants in fresh or
salt water.
B
Bivalve: Shellfish species that have a hinged two-part shell. They include oysters, clams, scallops, mussels and cockles.
Broodstock: Mature salmon from which milt (sperm) and roe (eggs) are extracted to produce the next generation of cultivated fish.
Brood year: The calendar year when the fish were born.
C
Carrying capacity:
(Fish) culture: Cultivation of fish from broodstock. In salmonid enhancement and ocean ranching, the fish are released from the hatchery. In salmon farming, the fish remain in captivity through their whole life cycle.
D
Disease: A condition of the body, or some part or organ of the body, in which its functions are disturbed or deranged. In fish, indicated by discoloration, mortality, behavioural changes (fish do not swim, or remain near surface), poor growth, changes in the quality of the flesh.
E
Ecosystem: A community of organisms and their physical environment interacting as an ecological unit.
Enhancement: The augmentation of wild stocks by rearing fish in hatcheries and then releasing them at different stages in their life-cycles.
Enzootic: Disease present to a particular region, such as IHN, that is naturally occurring.
Epizootic: Disease temporarily present in a population of animals, attacking many animals in a population simultaneously (like epidemic) – also called an "outbreak."
F
Fallowing: The process of leaving an aquaculture site unused for a period of time, in order to facilitate seabed recovery and rehabilitation (cf. abandonment).
Feral: Animals belonging to or forming a wild population ultimately descended from individuals which escaped from captivity or domestication.
Fish farming: A production system of raising fish in captivity for the duration of their life-cycle until they are harvested.
Fish habitat: Spawning grounds and nursery, rearing, food supply, and migration areas on which fish depend directly or indirectly to carry out their life processes
Fish stocks or Fish populations: all fish that are the same species, but may be genetically distinct from other stocks of the same species. For instance, wild sockeye salmon populations in the North Coast of BC are slightly genetically different than the wild sockeye populations located in the South Coast of BC, but they are all same species.
Fitness: The relative ability of a genotype (an individual) in its environment to successfully contribute offspring to the next generation. In salmon, fitness is frequently equated to the number of progeny produced per spawn.
Fry: Salmon that have emerged from gravel, completed yolk absorption, remained in freshwater streams, and are less than a few months old.
J
Juveniles: Salmon in their first year(s) of life, traditionally in freshwater streams, rivers or lakes
L
Life stage: For wild salmon the life stages are: alevins emerge from eggs and reside in the gravel, fry emerge from the gravel and reside in freshwater or migrate to the sea, parr (pre-smolt) reside and grow in freshwater, smolts are a transition phase from freshwater parr to seaward migrants, adults live at sea until migrating back to their natal streams to spawn. The period of these stages differs between salmon species. (Stages from fry to smolt also known as juveniles).
M
Morbidity: The prevalence and severity of impacts of disease.
Mortalities: Farmed fish that have died prior to harvest.
Motile: Lice that are beyond the infective stage.
P
Pathogen: Agent of disease/infectious agent. Those of concern here are viruses, bacteria and parasites. While the term is often used to include only the first two of these, usage in this report includes parasites.
Pathogenicity: Whether or not the normal functioning of the fish is affected and the chances of survival of the fish are reduced; the ability to cause a disease.
Population: Group of individuals of one species occupying a defined area and sharing a common gene pool. For wild salmon, a localized spawning group of fish that is largely isolated from other such groups.
Practical recovery time or "PRT": The interval from cessation of aquaculture operations to the time when diversity cannot be distinguished reliably from the reference value.
Productive capacity: The maximum natural capability of habitats to produce healthy fish, safe for human consumption, or to support or produce aquatic organisms on which fish depend.
R
Run: Genetically similar group of fish having a shared source and destination place or time. In the wild, the group of fish that return to the same geographic area (natal watershed), or that return at the same time period. On a salmon farm, the group of fish at a farm site.
S
Salmonid: A category of fish that includes salmon, steelhead and trout.
Shellfish: Shellfish are one type of invertebrate species (animals that do not have a backbone or spinal column) that has been successfully domesticated through aquaculture practice. Bivalve shellfish – meaning the animal has two shells like mussels, clams and oysters – are the predominant type of shellfish grown by Canadian aquaculture operators.
Smolt: A juvenile salmon that has completed rearing in freshwater and migrates into the marine environment. A smolt becomes physiologically capable of balancing salt and water in the estuary and ocean waters. Smolts vary in size and age depending on the species of salmon.
Stress: A response to a situation that is beyond the scope of what the animal normally encounters, although stressors may be frequent and numerous. Health may be looked at as the capacity to deal with stress without succumbing to disease.
T
Therapeutants: Medicines used to treat and control diseases, such as antibiotics or pesticides.
Transgenic fish: Fish that have genes inserted into their genetic make-up that may come from the same organism, but have been modified to enhance a trait (weight, length) the fish would not normally possess. The genes could also come from another, unrelated, organism.
V
Virulence: The ability of a microorganism to cause disease (what are the potential factors that lead to this? Warm water temperatures, low water levels, susceptibility of the fish due to physiological changes, etc.)
W
Wild salmon: Salmon are considered "wild" if they have spent their entire life cycle in the wild and originate from parents that were also produced by natural spawning and continuously lived in the wild.
Y
Year class: The brood year (year the fish was born) or the salt-water entry year that defines a cohort of fish.
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Some glossary terms are provided with permission of the Pacific Fisheries Resource Conservation Council |
