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Ichthyoplankton and Fish Recruitment Studies in Large Marine Ecosystems

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Ichthyoplankton and Fish Recruitment Studies in Large Marine Ecosystems Ichthyoplankton and Fish Recruitment Studies in Large Marine Ecosystems KENNETH SHERMAN, REUBEN LASKER, WILLIAM RICHARDS, and ARTHUR W. KENDALL, Jr. Introduction tablished by Congress in 1976 (Fig. I). In this paper we provide an over­ This law extended U. S. jurisdiction view of the research strategies and new Resource assessment studies of the to a 322 kIn (200-mile) wide strip of studies implemented by NMFS to over­ National Marine Fisheries Service ocean off all the U. S. coasts (over 3.5 come resource assessment problems 2 (NMFS) were expanded significantly million km ). posed by the large-scale temporal and during the middle 1970's to support the spatial biological and environmental conservation and management of ma­ changes influencing the abundance rine fishery resources within the U.S. K. Sherman is with the Narragansett Laboratory, levels of U.S. fishery resources within Fishery Management Zone (FMZ) es- Northeast Fisheries Center, National Marine the FMZ. The new studies are part of Fisheries Service, NOAA, Narragansett, Rl 02882; R. Lasker is with the La Jolla Laboratory, an NMFS-NOAA initiative known as Southwest Fisheries Center, NMFS, NOAA, La the Marine Resources Monitoring As­ Jolla, CA 92038; W. Richards is with the Miami Laboratory, Southeast Fisheries Center, NMFS, sessment and Prediction (MARMAP) ABSTRACT- Within the Fishery Man­ NOAA, Miami, FL 33149; A. Kendall is with program. agement Zone of the United States, seven the Seattle Laboratory, Northwest and Alaska The MARMAP program was built Large Marine Ecosystems (LME's)-ln­ Fisheries Center, NMFS, NOAA, Seattle, WA 98112. This paper is MARMAP Contribution around a matrix of existing NMFS sular Pacific, Eastern Bering Sea, Gulf MED/NEFC 83-24. fishery resource assessment activities of Alaska, California Current, Gulf of Mexico, Southeast Atlantic Shelf, and Northeast Atlantic Shelf-support multi­ billion-dollar fisheries, operating at differ­ ent trophic levels. The LME's are charac­ terized by unique bathymetry, hydrography, productivity, and population structure. To improve abundance forecasts of recruit­ ment success ofincoming year classes, two assessment strategies are used by NMFS in the LME's: I) Fisheries independent sur­ veys offish eggs and larvae on mesoscale grids of20-100 km at frequencies of two to twelve times a year to obtain estimates of the size of the spawning adult stocks, and 2) other studies within the mesoscale survey matrix aimed at discovering the processes controlling the annual recruitment success ofnew year classes. Processes under inves­ tigation include growth and mortality of eggs and larvae under variable density­ dependent predator-prey interactions and density-independent influences of changes in circulation, water-column structure, biological production, and pollution. The sampling designs of the multispecies ich­ thyoplankton surveys in the LME's provide measures-of spatial and temporal variabil­ ity within acceptable confidence limits for estimating changes in abundance levels of spawning stock sizes offthe northeast coast and in the California Current areas. Figure 1. - The 3.5 million km 2 area of the U. S. Fishery Management Zone. Oct.-Nov.-Dec. 1983,45(10-11-12) Gloucester, Ma'isachUM'It<; ~;::lr.:l:":ll:~r~(~~~',l/'llr:l'r'~(\'~ l- l- (:) Portland,O...,gon ------_.L Columhla Rl\'(,,1 ~ I~"('n('" '; Woods Hole. Mauachusetts f)evclOpl1H'II1 "lllgr,IOJ (, Northea<:'l h ... ht:flt:'l Center (r\W Rq,{1011l NORTHWEST REGION I ~t~~~\If)l(' l...lhoTato!"\, (:'\jEFe) Tiburon. California ---...... lihllWIl l..,nor..Hon (SWF<:) Narragansett. Rhode Island Narrttgan"ell Llbor;tlon jNEFC) Mont~rey. CaJifornia ---....... AtI"tnltl En\ ITO!llll(,IlI,11 (;roup PaniK EIl\lnllllllt'nl<l1 (NFFCI Croup (S\·n·C) Milford. Conneclicut Tuminal Island. California - _=" Milford Llhor;lIorv (~EFC) SOliI hwe"l R('~um (1Idqs.) Highland!J. Ntw Jer!JeY La Jolla, California Sttn"~ 11001.. I ..tborAlon (r\EFCl Southwesl h"heflec; Ct'nl("r 1111111\ ) La.loUi! I"I bora101 \ (SWF<:) Oxford. Maryland Oxford Lahoralory (NEfC) ~:I~~:1~lf~71~~t~~I::~I~('~~t'~olumbia Sen-ice Headqu;lrtt'ro; National SV<;ICllldlics Ltborarnry (NEFC) HAWAII ISW REGION) Beaufort., North Carolina Beaufort Laboratory (SEFe) Bay St. Louis. Mississippi :"l,IIHlflttl 1'I.-.heTI('<, CharleSlon, South Carolina l-llgll1('t'"flllg 1.,tlllJl,tIOI"V CharieslOn Laboratory (SEFe) ,Sf f(.) Pribilof hlands. Alaska Honolulu. Hawaii Miami. Florid. Prih.lo' IlllalHl ... HOllollllu LlhoTal(IT\ Snutheast Fi"hencs Center PI"O~ram (NW R('~lllll) (SWfC) Pascagoula, Mississippi (f1dqs.) i.~I~af;H'la 1.<lllllI.lI()f\ Miami l...ahoralOry (SEFe) Jun~au. Alaska St. ~tenburg, Florida ~~~~~aB~~~I~:~:~:~~~:\N WA F< 'j Panama City, florida --__... Southeasl Rq~ioll (Hrlqs.) II;lIl,llll,1 ell\ 1.,11'll1lAl()1"\ ,'f f( I Figure 2. - The four fisheries centers and associated laboratories of the National Marine Fisheries Service, and the five regional headquarters and related offices. including studies dealing with the anal­ Fisheries Center, Seattle, Wash., is tlVlty within each of these regions yses of catch statistics, the results of responsible for studying resources in comprise coherent ecological systems fishery surveys (pelagic, demersal, the Gulf of Alaska, eastern Bering encompassing broad geographic areas ichthyoplankton), fisheries oceanog­ Sea, and off the coasts of Washington designated as Large Marine Ecosys­ raphy, and fisheries engineering. A and Oregon. The Southwest Fisheries tems (LME's). description of the early development Center, La Jolla, Calif., has responsi­ The fishery resources within the of MARMAP program elements is bility for the studies of the living re­ LME's are subject to management by given in a series of planning docu­ sources of the California Current, Regional Fishery Management Coun­ ments prepared by NMFS with the Hawaii, and the Pacific Trust Territo­ cils, and management plans must en­ assistance of the Ocean Systems Divi­ ries. The Southeast Fisheries Center, sure optimal sustained yields based on sion of TRW Company! (TRW Sys­ Miami, Fla., assesses the resources ecological, economic, and social con­ tems Group, 1973a,b, 1974.) from North Carolina to the Florida siderations. The ecological decisions The coordination and integration Keys, and in the Gulf of Mexico and are based on the best scientific infor­ of investigational components of Caribbean. The Northeast Fisheries mation available. Each fisheries center MARMAP are major research activi­ Center, Woods Hole, Mass., studies conducts ichthyoplankton studies as ties of the four NMFS fisheries centers the resources on the continental shelf an important part of the overall (Fig. 2). The Northwest and Alaska from the Gulf of Maine to Cape Hat­ MARMAP assessment to support the teras. The energetically related bio­ councils in developing management I Mention of trade names or commercial firms does not imply endorsement by the National logical communities, bathymetry, and conservation plans for regional Marine Fisheries Service, NOAA. hydrography, circulation, and produc- fishery resources. 2 Marine Fisheries Review ALL SPECIES Fisheries Studies in 1973; Parrish, 1975; Andersen and 10 Large Marine Ecosystems Ursin, 1977; Sheldon et aI., 1977; * 810MASS Beddington et aI., 1979; Grosslein et **** *** ****** 8 ** From the turn of the century through aI., 1980; Laevastu and Favorite, 1981; **** * Laevastu and Larkins, 1981; Mann, the middle 1970's, fisheries studies 6 were mainly focused on the yields of 1982; Sissenwine et aI., In press; 2 3 single species. This was not due to any Jones ; Laevastu and Favorite ; Sher­ 4 4 YIELD man et aI. ). lack of awareness of the interaction ~... and interdependence of species, but These models deal with multispecies ~ .. rather to budget constraints on fisher­ fishery interactions at different trophic ies research institutions. However, levels. They are important approxima­ (J) from a fisheries management point of tions of the consequences of predator­ C 0 .....L.,--,--.--,----r---r--,-,--,--.---, E 1960 1970 1980 view, the best and most sought data prey dynamics, based on fishery­ C imposed selective mortality, and hold .9 6 follow an accurate prediction of future ** *** HERRING stock sizes and of the effect of different promise for providing a basis for the ** .. MACKEREL levels of fishing or environmental per­ management of marine ecosystems. 4 * turbation on the continued production For example, possible species replace­ * *** BiOMASS of economically viable resource popu­ ments of heavily fished mackerel and *** ****** lations. herring stocks with smaller, fast-grow­ ~Y'ELD At present, NMFS under MARMAP ing, economically less desirable spe­ o .....L.,--,...---.---r.....,...---r--,-,---r-=.-T.~.!..., has a more holistic approach to fishery cies have been reported for the North '960 1970 1980 Sea based on a multispecies predator­ assessment studies, with a focus on 4 SPRAT BIOMASS *** whole ecosystems and the multispecies prey model simulation supported by .. SANOEELS ** *** interactions at different trophic levels yield data (Andersen and Ursin, 1978) • NORWAY * * POUT ** ** that influence the annual production of (Fig. 3). A review of the fish-stock ••• • Y'ELD fish populations. There are no shortcuts replacement concept can be found in ******* to obtain the comprehensive popula­ Daan (1980). However, if ecosystem 1960 1970 '980 tion and environmental information models are to assume an appropriate required to improve forecasts of fish role in the management of fishery
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