,,"!>< MANCCRC..ANi~::,,"',,- ~ ~ r Zjfi>~ ~ 92 DEFINING FISHERIES A User's Glossary Kenneth J. Roberts Jerald W. Horst John E. Roussel JosephA. Shephard LOUISIANA SEA GRANT COLLFGF. ['ROGRAM Louisiana State Vniversity INTRODUCTION Theharvest of fish by commercialand recreationaltishermen is regulatedby federal LOUISIANA andstate agencies that develop plans by which SEA GRANT to managefishery resources.In so doing, College Program agenciesseek advice from fishermen and others involvedwith the fishing industry, Manage- ment plans include technical words and terms thatare difficult to understand,This glossary ~ LauISIAeA givesdefinitions that should help fishermen COOPERATIVE EXTENSION SERVICE understandthe scientific basis of management. EOIIISIENESTREE UNIVERSITT EGRIClj'LTUREI CENTER Thus, their comments and advice will be more usefulin planningand management. Kenneth J. Roberts, Putting fishery managementterms in Marine ResourceEconomics Specialist Louisiana Cooperative Extension Service nonscientificwords may makesome definitions Louisiana State University toosimple, but theauthors sought to getthe main idea acrosson each term. Some terms are Jerald W. Horst, Area Agent Fisheries! referredto by scientistsas letters or groupsof Louisiana Cooperative Extension Service letters acronymsland theseare listed at the end Louisiana StateUniversity of the publicationfor quick reference.The word fish is usedthroughout, and includesfinfish and John E, Roussel, Marine Fisheries Division shellfishspecies, A mail-inform is providedto Louisiana Department of Wildlife and Fisheries identify words and terms that need to be includedin a futureprinting. JosephA, Shephard, FisheriesResearch Division Louisiana Department of Wildlife and Fisheries Amberjack on front cover courtesy of Dr. Bruce A Thompson, LSU Coastal Fisheries Institute The researchthat resulted in this publication was A Seeanrll<al mortality. supported by the Louisiana SeaGrant College ABC Seeallourable biologicai catch. Program of Louisiana State University. Louisiana SeaGrant is a part of the National SeaGrant College AP Seeadtlisory panel. Program maintained by the National Oceanic and Atmospheric Administration, U.S. Department of AbsoluteAbundance The total number of a Commerce, and is also supported by the state of kindof fishin thepopulation. This is rarely Louisiana. known, but usually estimatedfrom relative abundance,although other methods may be used, Abundance Seerelatitv abundanceand absolute abundance. AdvisoryPanel AP! A groupof people appointedby a fisheriesmanagement agency to review information and give advice. Members ! July 1991 are usually not scientists, but most are familiar Louisiana SeaGrant College Program withthe fishing industry or a particularfishery. Louisiana StateUniversity Baton Rouge, Louisiana 70803-7507 Age Frequencyor Age Structure A breakdown Billfishes The familv of fish that includes of the different agegroups of a kind of fish in a marlins,sailfish and spearfish, population or»ample. BiomassThe total weight or volume of a Allocation Distribution of the opportunity to speciesin a given area. fish amonguser groups or individual». The share a user group gets is»omc time» based on BonyFishes Fish that havea bonyskeleton and hi»toric harvc»t amounts. belongto theclass O»teichthyc». Basically, this is all fishexcept for sharks,rays, skates, hagfi»h Allowable Biological Catch ABC! A term used and lampreys, by a managementagency which ref>r» to the rangeof allowablecatch for a speciesor species Bycatch The harvest of Fish or shellfish other group. Jt i» sct eachyear by a scientificgroup thanthe species for whichthe fishing year was createdby the managementagency, Thc agency set. Examplesare blue crabs caught in shrimp then takes the ABC estimate and»ct» the annual trawlsor sharkscaught on a tunalongline. total >tllo>oaf>lccate/> TAC!. Bycatch is also often called i»cia»nta!catcl>. Somebycatch i» kept for sale. AnadromousFish that migratefrom saltwater to fresh water to spav n. Angler A person catching fish or shellfish with C no intent to sc11.This includespcopje rcl a»ing the catch. C/E Seecate/> l>cr»»it of effort. AnnualMortality A! Thepercentage of fish CPUE Seec»tel> y<'r t>»it of >.'ffnrt, dying in oneyear due to both fishing and CatadromousFish that migratefrom fresh natural causes. water to»altwaterto spawn. Aquaculture The raising of fish or shellfish CatchThe total number or poundageof fish under somecontrols, Ponds,pens, tanks, or capturedfrom an areaover someperiod of time. other containers mav be used. Feed is often Thisinc]udcs fish thatare caught but releasedor used. A hatcheryis alsoaquaculture but thc fish discardedinstead of beinglanded. Thecatch are released before harvest size is reached. may take place in an area different from where ArtisanalFishery Commercial fishing using the fish are landed. /Mote:Catch, harvest, and traditional or small scaleyear and boats. landings are different. Availability Describeswhether a certain kind CatchCurve A breakdownof differentage ot'fish of a certainsize can be caughtby a type groupsof fish, showingthe decreasein numbers of gear in an area. of fish caught as the fish becomeolder and fess numerous or less available. Catch curves are often usedto estimatetotal mortality, Catch Per Unit of Effort CPUE; C/E! Th» numberof fish caughtby an amountof effort, BagLimit Thenumber and/or sizeof a species Typically,effort is a combinationof geartype, thata personcan legally take in a dayor trip. gearsize, and lengthof time gearis used. Catch This may or may not be the sameas a possession pcr unit of effort is often used as a measurement limit. of relativeabundance for a particularfish. Benthic Refers to animal» and fish that live on CatchStream The catch statistics for a kind or or in the water bottom. stockof fish over a periodof time, Catchability Coefficient q! The part of a stock Management Act of 1976as amended created that is caught by a defined unit of effort. the regionalcouncils. For example,the Gulf of MexicoFishery Management Council develops Charter Boat A boat availablefor hire, normally fisherypolicies designed to managethose by a group of people for a short period of time. species most often found in Gulf federal waters. A charter boat is usually hired by anglers. CrustaceanA group of freshwater and saltwa- CoastalMigratory PelagicFishes Several ter animalshaving no backbone,with jointed speciesof fish that live in open waters near the legs and a hard shell made of chitin. Includes coast, grouped together by the Gulf of Mexico shrimp, crabs,lobsters, and crayfish. FisheryManagement Council and South Atlan- tic Fishery Management Council for manage- Cumulative FrequencyDistribution A chart ment purposes,This includesking and Spanish showing the number of animals that fall into mackerel, cobia, dolphin, and little tunny. certain categories,for example, the number of fish caughtthat are lessthan onepound, less Cohort A group of fish spawned during a given than threepounds, and more than threepounds, period, usually within a year. A cumulativefrequency distribution showsthe numberin a category,plus the numberin Cohort Analysis Seevirtual populationanalysis previous ca tegories. Commercial Fishery A term related to the whole processof catching and marketing fish and shellfish for sale. Common Property Resource A term that Demersal Describes fish and animals that live indicates a resourceowned by the public. It can near water bottoms. Examples are flounder and be fish in public waters, trees on public land, croaker. and the air. The government regulates the use of a common property resource to ensure its DirectedFishery Fishing that is directedat a future benefits. certainspecies or group of species.This applies to both sport fishing and commercialfishing. CompensatoryGrowth An increasein growth rate shownby fish when their populations fall Disappearance Z'! Measures the rate of decline below certain levels. This may be caused by less in numbersof fish caughtas fish becomeless competition for food and living space. numerousor lessavailable, Disappearanceis most often calculated from catch curves. CompensatorySurvival A decreasein the rate of natural mortality natural deaths! that some fish show when their populations fall below a certain level. This may be caused by less competition for food and living space. EEZ See exclusive economic zone. Condition A rnathernatical measurement of the EIS Seeenvironmental impact statement. degree of plumpness or general health of a fish or group of fish. ESO Seeeconomics and statistics office, ConfidenceInterval The probability, based on EconomicEfficiency In commercialfishing, statistics, that a number will be between an thepoint at whichthe addedcost of producing upper and lower limit. a unit of fish is equalto what buyerspay. Producingfewer fish wouldbring the costlower Council Indicates a regional fishery manage- than what buyersare paying. Producingmore ment group. The Fishery Conservationand fish would raise the cost higher than what Ex-vessel Refers to activities that occur when a buyers are paying. Fish harvesting at the point commercial fishing boat lands or unloads a ot economic efficiency produces the maximum catch. For example, the price received by a economic yield. See»zaxi»ru»recorrorrric yield and captain for the catch is an exvesselprice. economic rerrt. Exclusive Economic Zone EEZ! All waters Economic Overfishing A level of fish harvest- from the seaward boundary of coastal statesto ing that is higher than that of economic effi-