u.s. globec newsusglobec.org/newsletter/news.pdf.files/news8.pdfu.s. globec news no. 8 -- march 1995...

U.S. GLOBEC NEWS No. 8 -- March 1995 1

March 1995

Cod Fishery Collapses and North Atlantic GLOBECby Michael Sinclair and Fred Page

Number 8

U.S. GLOBECNEWS

U.S. GLOBEC: A Component of the U.S. Global Change Research Program

The collapse of the groundfish fisheries in the northwestAtlantic has focused the attention of both management

and science on critical gaps in knowledge. Reportedlandings of Atlantic cod from 1970 to 1992 are shown inFigure 1. There are differences between the patterns for thenortheast and northwest Atlantic stocks. Off North Americathere was some rebuilding of the cod resource followingextension of jurisdiction to 200 miles in 1977, and theremoval of foreign fishing. However, cod abundance hasdeclined sharply since the late 80s in most areas of itsdistributional range. For some cod management units,spawning stock biomasses are sufficiently low that fisherieshave been closed since 1993.

The socio-economic impacts of the closures of thesegroundfish fisheries (particularly in Newfoundland, easternNova Scotia, and northern New Brunswick) are yet to befully understood. There is no doubt, however, that thecollapse of the groundfish fisheries is a crisis of historicproportions for Atlantic Canada. Perhaps comparison to theHighland Clearances of the late 1700s to early 1800s inScotland, when crofters were displaced from their rented

land to facilitate sheep farming by the property owners, isnot inappropriate. Many of the displaced crofters, undergreat hardship, emigrated to the colonies (including AtlanticCanada). The displaced fishermen and processing plantworkers of today, however, have no new frontier to move to.They are experiencing, at a very personal and emotionallevel, the tragedy associated with inadequate management ofrenewable resources.

Governments are now faced with the task of how toimprove the management of these resources. As part of this,a number of fundamental questions involving populationregulation of marine fish must be addressed. In this article,we pose several of these management questions, summarizethe relevant conceptual framework in the ecological litera-ture, and discuss how GLOBEC research in the NorthAtlantic may generate explanatory power and answers. Forthis latter part, research results from our modelling team areused to illustrate issues.

Figure 1. Trends in landings for cod from 1970 to 1992 (from FAOstatistics).

(Cont. on page 2)

In this issue...

1 Cod Collapses and GLOBEC4 MARE COGNITUM6 Technology Forum6 ATOLL Laboratory8 U.S. GLOBEC Calendar9 TASC Working Group Formed12 Southern Ocean Modeling AO13 Okhotsk Sea Workshop13 GAIM Science Conference14 U.S. GLOBEC Web Site14 PACLIM Workshop15 Carrying Capacity and Climate Change Workshop

2 U.S. GLOBEC NEWS No. 8 -- March 1995

Collapses—(Cont. from page 1)

species.Does the trawling activity of the

groundfish fishery diminish thebenthic food supply to commerciallyimportant species? Those who inferthat there is an impact of trawling onthe sustainability of the groundfishfishery assume that groundfish popula-tions are regulated by intra-specificcompetition for food, in this case at thejuvenile and adult stages of the lifecycle.

What management objectivesare practical given the degree ofenvironmental variability in theNorth Atlantic? The ecological issueincludes the role of physical oceano-graphic processes on marine fish

population regulation, and the degree towhich ecosystem regime shifts occur.The practical issue concerns the degreeto which we are able to monitor andregulate fishing in light of thesepopulation processes and shifts.

Conceptual Framework Un-derlying Regulation of MarinePopulations

Responses to these managementquestions require scientific understand-ing of population regulation. Thiscomponent of ecology was a hot area ofdebate in the 1950s and 1960s. Unfor-tunately, the debate produced little

Table 1. Hypotheses that address geographic patterns in populations, their meanabundance, and their year-class variability.

Mean Year-classHypothesis Pattern Abundance VariabilityMigration Triangle (Harden Jones 1968) XMatch-mismatch (Cushing 1973) X X XStable Ocean (Lasker 1978) XEncounter rate (Rothschild and Osborn 1988) XMember-vagrant (Sinclair and Iles 1989) X X X

POPULATIONFEATURE HYPOTHESISPHYSICALOCEANOGRAPHICPROCESS

KEYBIOLOGICALFEATURESPattern migration triangle persistent residualcurrents drift from spawningarea to nursery areaPattern member-vagrant re-circulation limitation ofdispersal fromspawning areaAbundance match-mismatch not relevant density-dependentlarval feedingAbundance member-vagrant size of re-circulationfeature density-dependentvagrancyVariability match-mismatch seasonal verticalstratification larval feedingsuccessVariability stable ocean summer wind mixing larval feedingsuccessVariability encounter rage summer turbulentmixing larval feedingsuccessVariability member-vagrant horizontal circulation vagrancy fromappropriate

Table 2. Physical oceanographic processes associated with population regulation under diverse hypotheses.

Four Management Questions

What criteria should be used todefine and open a species/areamanagement unit to fishing? Anecological issue relevant to thisquestion is an understanding of thepatterns of geographically distinct self-sustaining populations and theirrespective “minimum spawning stock”levels. Population patterns are definedby the spatial location and scale of birthsite fidelity and we need to betterunderstand the time scales of recoveryof spawning components that havebeen fished close to commercial, andperhaps biological, extinction.

Does the management strategyneed to include a multi-speciesecosystem approach in order to meetthe objectives of fisheries manage-ment? Those who argue in theaffirmative infer that the abundance ofgroundfish population is regulated byfood chain interactions, and that theimpacts of fishing on one speciesaffects predator/prey relationships ofco-occurring commercially important (Cont. on page 3)



explanatory power concerning whatfactors regulate abundance, andconsensus on the relative importance ofdensity-dependent and density-independent factors is still lacking.Eventually ecologists moved on toother issues.

The International GLOBECprogram provides an opportunity forrenewed focus on population regulationof marine species, with a particularemphasis on cod for the North AtlanticGLOBEC/ICES component. Formarine fish there is a rich conceptualliterature, including a number ofcompeting hypotheses on variousaspects of population biology (Table 1).It is helpful to consider these hypoth-eses in the context of three aspects ofpopulation regulation: pattern, abun-dance, and variability (Sinclair 1988;Sinclair and Iles 1989). The hypoth-eses and their associated physicaloceanographic processes are listed inTable 2.

The migration triangle hypothesisstates that the geographic patterns ofmarine fish populations are establishedand maintained by residual currentslinking spawning locations to juvenilenursery areas. In contrast, the member-vagrant hypothesis states that thepatterns are maintained by areas thatlimit the dispersal and advection ofeggs and larvae during the early part ofthe early life history (i.e., areas ofretention of eggs and young larvae).The competing hypotheses identifydifferent physical/biological couplingprocesses as being critical to thedefinition of spawning populations andas such are mutually exclusive.

The match-mismatch hypothesisstates that mean population abundanceis regulated in a density-dependentmanner by the plankton food availablealong the drift route. At high popula-tion levels the larvae become relativelymore food limited, and vice versa. Themember-vagrant hypothesis states thatmean abundance differences betweenpopulations of the same species aredefined by the size of the physical

oceanographic features that restrictdispersal of eggs and early stage larvae.Furthermore, it is argued that density-dependent vagrancy (i.e., an increase inloss rate at higher spawning stocklevels, and vice versa) can regulateabundance without density dependenttrophic processes. Again, the compet-ing hypotheses identify differentoceanographic processes.

Three of the four hypotheses whichaddress temporal variability in theabundance of year-classes focus onfood availability during the larval stage.The match-mismatch hypothesis statesthat the variable timing of the seasonalphytoplankton bloom in relation to afixed period of spawning generatesinterannual differences in the matchbetween the zooplankton productioncycle and the period of fish larvalfeeding. The key physical oceano-graphic process is the seasonal devel-opment of vertical stratification in thewater column that permits phytoplank-ton blooms to develop. The stableocean hypothesis states that verticallystratified (i.e., low mixing) conditionsare needed to generate high localconcentrations of food at thepycnoclines for favourable larvalsurvival rates. These concentrations,however, are broken down duringstrong wind events. Thus, the physicalprocess of importance is the frequencyand intensity of wind mixing during thelarval feeding stage, with low windsbeing considered favourable for larval

survival. The encounter rate hypothesisis almost the opposite of the stableocean hypothesis; increased turbulenceenhances the encounter rate betweenfish larvae and their prey. Thus, yearsof increased wind mixing and areas ofstrong tides should improve larvalfeeding success and generate relativelyhigher survival rates.

In the member-vagrant hypothesisboth food chain and spatial displace-ment processes contribute to variableloss rates from the appropriate geo-graphical area for the population. Thetwo categories of processes can act in adensity-dependent or a density-independent manner. If vagrancy isitself density dependent for a particularpopulation, then there is no necessityfor density dependent trophic limitationof abundance.

In sum, the five hypothesesidentified above involve differences inoceanographic processes, physical/biological coupling mechanisms, andtheir characteristic time scales. Severalof the hypotheses assume that larvalfeeding is the key process. Much of thefisheries research during the past twodecades has been on the year-classvariability aspect of populationregulation. Prediction of the impacts ofclimate change are dependent uponwhich hypothesis or hypotheses bestcapture the realistic dynamics for agiven population and time.

Figure 2. Vertical andmeridional dependence ofparticle retention upstream of theGreat South Channel. Particlesthroughout this section werereleased every 10 m verticallyand every 500 m horizontally.Particles released within thediagonally hatched area wereretained; those within thevertically hatched area were lostfrom the Bank. Black regionindicates the Bank’s bottomtopography.

(Cont. on page 16)


MARE COGNITUM is a regional GLOBEC programnow getting underway in Norway. Like the U.S.

GLOBEC Georges Bank Program, the scientists funded toparticipate in MARE COGNITUM are from a governmentfunded laboratory and academic institutions. They also havebeen working during the past couple of years on pilotprojects and 1995 is their first major field effort. Themeeting described below was the PI meeting that is intendedto occur annually.

The meeting was held at the Solstrand Fjord Hotel,about 40 km south of Bergen, Norway. This hotel sits southfacing on the edge of Fusafjord which is a small arm of thelarger Bjornafjord. The fjord waters, together with therugged snow capped mountains rising up to the south andeast of the fjord, provided a spectacular setting for themeeting. This will almost certainly be the site for next year’sannual MARE COGNITUM meeting.

In attendance were individuals from a number ofNorwegian institutions and universities who representedgroups that were funded by the Norwegian Research Councilto participate in MARE COGNITUM. Also in attendancewere representatives from adjoining countries who will becollaborating in this International GLOBEC project. Thecountries represented were the Faroe Islands, Iceland, andRussia. In addition, Piers Chapman represented U.S. WOCEinterests in the Norwegian Sea, and I represented U.S.GLOBEC’s Georges Bank Program. The official languageof the meeting was English.

The principal objectives of the meeting were 1) toprovide a forum for collaborating investigators to presenttheir ideas and any preliminary results that they might havewith regard to the MARE COGNITUM research program,and 2) to meet together in smaller groups to refine the cruiseplans for 1995, 96 and 97, to discuss the modelling activities,and to consider what steps need to be undertaken to fosterinternational aspects of the research.

The meeting started at noon on Monday the 27th andfinished at noon on Wednesday the 29th. During the first twodays, the investigators made their presentations. The lasthalf-day was used for working group sessions.

Hein Rune Skjoldal reviewed the goal of the programand major programmatic components. The goal is to identifyand quantify the most important factors and mechanismscausing variability in the ecology of the Nordic Seas with theaim to predict fluctuations in ocean circulation, production,and fish stocks. There are three programmatic compo-nents—ocean climate, resource ecology, and carbon cy-cling—each with a specific goal and objectives.

Ocean Climate aims to describe and understand themost important mechanisms responsible for variability inocean climate. Some objectives are:

• To describe variations in the influx of Atlantic water tothe Norwegian Sea.

• Establish quantitative relationships between the variationof influx and the different branches of Greenland andNorwegian Seas.

• To establish quantitative relationships for interactionsbetween ocean and atmosphere (heat flux, wind stress).

• To identify and quantify mechanisms causing or influenc-ing periodic variations in ocean climate.

• To construct models based on fundamental knowledge ofmechanisms, which can be used to forecast the develop-ment of ocean climate on time scales from one to severalyears.Resource Ecology’s goal is to describe the structure and

function of the ecosystem in the Norwegian Sea and quantifychief mechanisms regulating the effect of climate variationon production and size of fish stocks (herring and cod).Some objectives are:

• To describe pelagic food webs of the Norwegian Sea.• To quantify new harvestable production and its spatial/

temporal variation.• To describe the structure and dynamics of key zooplank-

ton and fish (mesopelagic) and how these populationsare adapted to or influenced by the large-scale circula-tion in the Greenland and Norwegian Seas.

• To establish relationships between growth, maturation,and migration of herring as a function of stock size,predation, and ocean climate.

• To determine trophic interactions between blue whiting,herring, and mesopelagic fish and the effects of a herringstock increase on other stocks (the last herring crash,blue whiting increased).

• To determining food requirements for salmon andestablish relationships between variations in its foodconditions and its growth in the Norwegian Sea.

• To identify regulatory mechanisms and quantify effectsof variations in ocean climate and zooplankton popula-tions in the Norwegian Sea on recruitment and year-classstrength of herring and cod.

• To determine the effects of life cycle and migration ofzooplankton and fish on the distribution and feedingecology of marine mammals and sea birds.

• To construct models to capture the essence of regulatoryforces and mechanisms controlling stocks.The Carbon Cycling effort is concerned with quantify-

ing the vertical flux of carbon and pathways for the sinkingof CO

2 to depth. Objectives are:

• To specify and quantify the effects of meteorological andphysical oceanographic factors on the spring phytoplank-ton bloom and annual primary production.

Report of MARE COGNITUM Meeting in Norway27-29 February 1995

contributed by Peter Wiebe

(Cont. on page 5)


MARE COGNITUM—(Cont. from page 4)

• To specify and quantify the role of zooplankton and fishon the magnitude and variability of the sedimentation ofbiogenic matter to great depths and the sea floor.

• To specify the mechanisms regulating the interaction ofphysical and biological processes determining thedegree of new (nitrate-based) production.

• To specify the mechanisms regulating the dominance ofcertain phytoplankton taxa (e.g. diatoms, Phaeocystis,coccolithophorids) and quantify the role of algal type forthe sedimentation of biogenic material out of theeuphotic zone.

• To develop models of the biological pump based onknowledge of mechanisms and vertical structure of thewater column.Individual investigators made presentations on fish

ecology and fisheries (13 presentations), internationalcollaboration and activities (6), plankton dynamics (7), andphysical oceanography (5).

The Nordic Seas area (Norwegian Sea (2 basins),Icelandic Sea, and Greenland Seas) is substantial—about 2.5million km2. For comparison, the Georges Bank study areais about 150 thousand km2 or approximately six percent ofthe Norwegian Sea area. Thus, there is a substantial require-ment for shiptime to cover this sea area. In 1995, a numberof ships are scheduled to participate in MARE COGNITUM.Norwegian cruises will cover the late winter, spring, andsummer period (February to August) (see Box).

The top three ships will be used to conduct a mix oflarge-scale surveys of the Norwegian Sea and smaller scaleprocess work. The specific MARE COGNITUM cruises are

marked with an MC; the others represent cruises wheresamples relevant to MARE COGNITUM will be collectedand shared. The other two ships will conduct more localshelf/slope studies off northern Norway. Iceland willconduct four large-scale surveys in the waters around theisland, and will occupy several transect lines 10 times duringthe year. The Faroes will conduct 3 surveys around theirwaters with one cruise specifically directed towards herring.The Russians will conduct a survey of the southern Norwe-gian Sea in June which will focus on herring, but willinclude other pelagic fish, plankton, and hydrography.

International cooperation of both logistics and sciencewas discussed. Logistical cooperation issues that arosewere:

• Common Sampling Protocols: WOCE and JGOFS haveprotocols that should be followed wherever possible.Measurements or use of instrumentation not coveredshould have agreed upon protocols developed.

• Common data bases. Need to establish ways to exchangeinformation and data.

• Exchange of cruise personnel.Scientific cooperation issues that arose were:

• Large-scale modelling• Linking regional models with basin scale/global models.• Genetics, otoliths: need to exchange material.

What is envisioned as the next step is a series of smallmeetings or workshops attended by representatives of thecollaborating countries to focus attention on:

• Common protocols and analysis• Data management and documentation.

• The North AtlanticTeleconnections (SeeSaw -NS/EW)

• Genetics [zooplankton/fish(cod/herring)]

• Otoliths [gadids and clupeiids)• Exchange of personnel

between programs (emphasison young scientists).One point that was empha-

sized was that ICES was going toestablish a secretariat forGLOBEC (and cod and climatechange?) which is intended to helpcoordinate activities in the NorthAtlantic and foster fruitfulinteractions. (Peter Wiebe is asenior scientist at the Woods HoleOceanographic Institution and ischair of the U.S. GLOBECGeorges Bank Executive Commit-tee) ∆∆∆


Technology Forum(Editors Note: Technology Forum isintended to stimulate thought anddiscussion on diverse oceanographictechnology issues. We welcomecontributions on technological issuesrelative to ocean science, but particu-larly to U.S. GLOBEC.)

The ATOLL Laboratory and other InstrumentsDeveloped at Kiel

by Uwe Kils

The ATOLL Laboratory consists ofthree banana-shaped fiberglass hulls(Fig. 1). These 25 meter long hulls canbe connected in series for transporta-tion. At the measuring site they areswitched into a horseshoe-shapedarrangement. In this operational modethe structure surrounds 150 m3 of thesea. Although the 5 meter wide hullsoffer 75 m3 of laboratory space, 220m3 of supply- and storage-facilities and350 m3 deck area, they project only 38cm below the surface and have a 2.8 mwide flat curved cross-section. Thesmall submergence minimizes distur-bances of the natural turbulenceregime. The lagoon opening is orientedtowards the sun for natural lightregime. The hulls are not coated withantifouling paints and are constructedonly from fiberglass, stainless steel,aluminum and wood to minimizechemical interference. The maininstrumentation room (25 m3) is air-conditioned to protect the electronics.All displays and controls are central-ized in a glasshouse on deck (30 m3) togive a good overview for the operators.The lab can accommodate three

scientists easily. A small lecture room isavailable for teaching.

An underwater observation roomallows for a direct inspection of theinvestigated scenery and control of theinstrumentation via two 40 x 40 cmwindows located 20 cm below the watersurface. The water around these win-dows is accessible with scientificequipment via four portholes. Airpressure in the observation room can beincreased to allow opening of theunderwater portholes to change theglasses or mount equipment onto theoutside of the windows without dockingthe lab. Five balconies give access 10cm above sea level; four of these aresheltered. Underwater bubble curtainssoftly guide the fish schools into thescanned areas, or prevent their escapeduring disturbances. After the in situmeasurements are complete, the organ-isms can be captured by raising a pop-up-net from below. This provides animalsfor taxonomic identification and forestimation of condition indices, enzy-matic activity, and RNA/DNA relations.

A crane-deployed boat is availableto assist in mounting instrumentation

near the lab and for monitoring thenearby environment. The boatssystems are connected to the laboratorycomputer via a radio link. Positioningand tracking of the boat is done byRADAR or SONAR from the lab. Thelaboratory is also equipped to supportdiving. Air is supplied from a lightumbilical for extended and relativelyquiet underwater inspections.

The central processing unit (CPU)is a CMOS industry microcontroller,communicating on a private andexclusive frequency with the main-frame of the institute. Several func-tions can be remotely controlled andevaluated by telephone. The CPUsystem performs all alarm functions aswell as a “call on event” systemtriggering an EUROCALL beeper. Thelab has been working autonomously formonths with only occasional checks forretrieving tapes and disks. Processeddata and selected images are transferredby radio communication. On-line dataprocessing of the acoustics, optics andphysics is done on a UNIX workstation(NeXT cube, RAM capacity 40 Mbyte)and several MOTOROLA 680XXsubsystems. Data compression (Delta-and JPEG) is conducted on board andprocessed data are stored on rewritableoptical disks. Because data inspectionand image analysis can be completedshortly after data acquisition, smalladjustments of the scanning setups canreadily be performed. SP highband u-matik and HI8 machines are used formass storage of the raw optical andacoustical data.

Some instruments are mounteddirectly on the hulls of the lab; othersare carried by remotely operatedvehicles (ROVs). For some types ofexperiments, e.g., behavioral studies,the propulsion systems of the ROVs

Figure 1. The ATOLL floating laboratory showing tethered ROV with attached ecoSCOPE.(Cont. on page 7)


(Cont. on page 11)

cause disruption of the natural hydro-dynamic environment. We minimizethe hydrodynamic disturbances bypositioning the ROV using threenegatively buoyant thin rubber bandsand a variable buoyancy system (seeFig. 1). This operational mode allowsfor a quiet approach from belowtowards the highly evasive organismswith minimum disturbance to thenatural turbulence- and light-regime.

A scanning SONAR is used tolocate the juvenile herring schools,guide the ROV, and for quantifyingpositions, distances and speeds.Salinity, temperature and oxygen aremeasured with probes, water velocitywith acoustics and microturbulenceswith optics. Plankton-, particle- andbubble-concentrations and their sizedistributions are measured with anoptical plankton recorder (OPR) (KILS1981, 1989), with high resolutionacoustics (KILS et al. 1991), or withnet- and pump-samples. Low-lightcameras and high speed video cameraswith shuttered LASER-sheet or infraredLEDs are used for quantification ofanimal behavior and for control of theexperimental setup (STRICKLER et al.1992). The ecoSCOPE (KILS 1992),an endoscope-system for non-invasiveoptical measurements, is used to recordthe microscale dynamics and behaviorof the highly evasive herring. Thedisturbance of the microturbulences bythis sensor is relatively low, and its datamake possible evaluation of micro-structures of the flow field. TheecoSCOPE can be mounted directly tothe floating platform or can be de-ployed using an ROV.

For the evaluation and visualiza-tion of ocean- and bio-dynamics,dynIMAGE software has been devel-oped (KILS 1992). First, dynIMAGEcompensates for the swaying androlling of the optics due to low-frequency microturbulences andprepares the raw data for evaluations ofanimal-motion and high-frequencymicroturbulences. Then, video-clipsare reconstructed from the processed

images for visualization of the fastoceanographic processes.

Investigations to date have concen-trated on one of the most important foodchain transitions: the linkages betweenthe early life stages of herring (Clupeaharengus) and their principal prey(copepods). A major hypotheses offisheries ecologists is that themicrodistribution of prey, themicroturbulence of the ocean, or theretention conditions are normally notsuited to allow strong year classes offish to develop. In most years morethan 99% of herring larvae do notsurvive. Occasionally however,physical and biotic conditions arefavorable, larval survival is high, andlarge year-classes result. The aim ofour investigations using the ATOLLlaboratory and the instrumentationdescribed above is to improve ourunderstanding of the effects of small-scale dynamics on fish feeding, predatoravoidance, and year-class strength.

Scientific Questions

What are the effects of the naturallight gradient on predator-prey interac-tions? How can the predator best seethe prey without being seen? How doesthe focussing of small waves oscillatinglight regime influence camouflage andattack strategy? What are the influ-ences of the different frequencies ofmicroturbulences? How do such effectschange at the moment when herringlarvae join into schools? What roledoes the phenomenon of aggregationplay? Does ocean physics create oralter organism-aggregations? Can thedynamic of aggregations effect oceanphysics at the microscales? Are thereeffects of the surface waves? What arethe distribution and dynamics ofmicrobubbles caused by turbulencesand gas-oversaturations? How can theorganisms orientate in respect to micro-gradients of the ocean physics? How dothey survive in the direct vicinity ofundulating anoxia and hypoxia? Whyare eelpouts, sticklebacks and herringsso extremely successful in the Balticwhile cod is not? What are the effects

and functions of schooling for feedingand microscale-orientation? All thiscan best be investigated in situ.

The areas of investigation are theestuaries of the western Baltic. Thedrastic ecological shifts during the lastdecades qualify this area as an excellentexperimental site for the examination ofglobal change effects on marineecosystems. Plankton concentrations ofup to 800,000 cells Prorocentrumminimum per milliliter are a challengefor herrings searching prey under thedrastically deteriorated visibility — anda challenge for the scientists to quantifytheir strategies.

The laboratory has been in opera-tion since 1982. It was a donation fromthe ATOLL Swimming StructureDevelopment Company, München,Kaiserplatz 8. The company is basedon the ATOLL trademark and theATOLL international patents. TheBMFT Ministry of Science and Tech-nology funded the first scientificexperiments on behavioral studies inmarine aquaculture. It has been run forthe last four years under theVOLKSWAGEN Bio-Science-Awardand by inputs from SONY, NeXT,ATARI, BP, ARD, ZDF, SAT1,RTLplus, GREENPEACE, the Ministryfor Nature and Environment Schleswig-Holstein, the Kiel-Canal Administra-tion, and some private sponsors.

Summary of Optics Develop-ments at the IfM, Kiel:

Optical Ichthyoplankton Recorder(Schnack, Welsch, Wieland, Kils):Towed GULF III type net similar toOrtner et al. (1981) but with a videocamera mounted at the net end, imageand data transmission via singleconductor cable, prototype employedsince 1990 on herring and cod surveysin the North Sea and Baltic. Distribu-tion, large scale long time seriesmonitoring.

Optical Zooplankton Profiler (Lenz):Vertical towed net-system, image and

ATOLL—(Cont. from page 6)


1995

5-6 April: U.S. GLOBEC Scientific Steering Committeemeeting, Corvallis, OR, USA. Contact: H. Batchelder,Department of Integrative Biology, University of Califor-nia, Berkeley, CA 94720-3140 (Phone: 510-642-7452;FAX 510-643-6264; Internet:[email protected])

5-6 April: Understanding Earth: Retrospectives andVisions, A conference to be held at the National PressClub in celebration of the 25th anniversary of Earth Day,Washington, DC. Contact: ERIM/Global Change Confer-ence, P.O. Box 134001, Ann Arbor, MI, USA (Phone:313-994-1200 x3234; FAX: 313-994-5123; Internet:[email protected])

18-21 April: The Oceanography Society's (TOS) FourthScientific Meeting, Newport, Rhode Island, USA. Con-tact: J. Rhodes, The Oceanography Society, 4052 TimberRidge Drive, Virginia Beach, VA 23455 (Phone: 804-464-0131; FAX: 804-464-1759; Internet:[email protected])

19-20 April: U.S. GLOBEC Workshop on ClimateChange and Carrying Capacity in the North Pacific,Seattle, WA, USA. Contact: A. Hollowed, Northwest andAlaska Fisheries Science Center, 7600 Sand Point Way,Seattle, WA 98115-0070 (Phone: 206-526-4223; FAX:206-526-6723; Internet: [email protected])

2-5 May: The 12th Annual Pacific Climate (PACLIM)Workshop, Pacific Grove, CA, USA, This years themesession is "Interdecadal Climate Variability over thePacific and Western Americas". Contact: D. Gautier, U.S.Geological Survey, Box 25046, MS 934, Federal Center,Denver, CO 80255 (Phone: 303-236-5740; FAX: 303-236-8822; Internet: [email protected])

9-12 May: First International Joint Global Ocean FluxStudy Scientific Symposium, Villefranche-sur-mer,France. Contact: E. Gross, Executive Director SCOR,Dept. Earth and Planetary Sciences, The Johns HopkinsUniversity, Baltimore, MD 21218 USA (Phone: 410-516-4070; FAX: 410-516-4019; Internet:[email protected])

U.S. GLOBEC Calendar

(Cont. on page 9)

May (tentative): Living Resources of the Azov-BlackSeas and their Rational Use, Kerch, Crimea, Ukraine.Contact: V. Yakovlev, Director, YugNIRO, 2 SverdlovStreet, Kerch 334500, Crimea, Ukraine (Phone: (06561)210-65; FAX: (06561) 215-72; Internet:[email protected])

1-3 June: First Open Meeting of the Human Dimensionsof Global Environmental Change Community, Durham,NC, USA Contact: Global Environmental ChangeProgram, Social Science Research Council, 605 ThirdAvenue, New York, NY 10158, USA (Phone: 212-661-0280; FAX: 212-370-7896; Internet:[email protected] or [email protected])

11-15 June: American Society of Limnology and Ocean-ography Summer Meeting, Reno, NV, USA. Contacts: R.Wharton, Jr., Desert Research Institute, P.O. Box 60220,Reno, NV 89506 (Phone: 702-673-7300; FAX: 702-673-7397; Internet: [email protected]) or D. Garrison,Institute of Marine Sciences, University of California,Santa Cruz, CA 95064 (Phone: 408-459-4789; FAX: 408-459-4882; Internet: [email protected])

12-16 June: ICES International Symposium on Fisheriesand Plankton Acoustics, Aberdeen, Scotland. Contact: E.J. Simmonds, Marine Laboratory, P.O. Box 101, VictoriaRoad, Aberdeen, Scotland AB9 8DB, United Kingdom(Phone: +44 224 876544; FAX: +44 224 295511)

19-24 June: PICES Workshop on the Okhotsk Sea andAdjacent Areas, Vladivostok, Russia. Contact: PicesSecretariat, c/o Institute of Ocean Sciences, Sidney, B.C.,Canada. V8L 4B2 (Phone: 604-363-6366; FAX: 604-363-6827; Internet: [email protected])

26 June-2 July: International Larval Fish Conference,Sydney, Australia. Contact: C. Jones, Applied ResearchLaboratory, 1034 W 45th St., Old Dominion University,Norfolk, VA 23529 USA (Phone: 804-683-4497; Internet:[email protected])

2-14 July: International Union of Geodesy and Geophys-ics, XXI General Assembly, Boulder, Colorado, USA.Contact: American Geophysical Union, 2000 FloridaAvenue NW, Washington, DC 20009 (Phone: 202-462-6900; FAX: 202-328-0566; Internet:[email protected])


meeting, Washington, DC, USA. Contact: H. Batchelder,Department of Integrative Biology, University of Califor-nia, Berkeley, CA 94720-3140 (Phone: 510-642-7452;FAX 510-643-6264; Internet:[email protected])

11-13 October: International Symposium on Biology,Management, and Economics of Crabs from High LatitudeHabitats, Anchorage, AK, USA. Contact: B. Baxter,Alaska Sea Grant College Program, University of AlaskaFairbanks, P.O. Box 755040, Fairbanks, AK 99775-5040(Phone: 907-474-6701; FAX: 907-474-6285; Internet:[email protected])

16-22 October: North Pacific Marine Science Organiza-tion (PICES) Fourth Annual Meeting, Qingdao, PeoplesRepublic of China. Contact: Pices Secretariat, c/o Instituteof Ocean Sciences, Sidney, B.C., Canada. V8L 4B2(Phone: 604-363-6366; FAX: 604-363-6827; Internet:[email protected])

31 October-2 November: California Cooperative FisheriesInvestigations (CalCOFI) Annual Meeting, Lake Arrow-head, CA, USA. Contact: G. Hemingway, Marine LifeResearch Group, Scripps Institution of Oceanography,University of California San Diego, La Jolla, CA 92093-0227 (Phone: 619-534-4236; FAX: 619-534-6500;Internet: [email protected])

the resting stage and methods for mortality estimation.Everyone received those in advance so that we arrivedprepacked with relevant information, not to mention pointsto argue with erring authors. Our first day was spentpresenting and discussing those papers, then celebrating ournew (or renewed) acquaintance in one of the world’s mostexpensive restaurants (which cluster in Oslo). Many of thepapers have been revised after the meeting and are in reviewfor publication together as an issue of Ophelia. The secondday we spent on both plenary and working party debatesabout the priorities for research on C. finmarchicus. Anamorphous mass of prose was produced which was laterhammered into a report to ICES by Kurt Tande. We dividedthe discussion and report into four themes, which I list herewith precis of the conclusions about each:

I. The Interplay between Generation Cyclesand Large-Scale Circulation Patterns in Oce-anic and Shelf Areas.

Calanus finmarchicus is a prominent component of shelf

(Cont. on page 10)

Calendar—(Cont. from page 8)

TransAtlantic Studies of Calanus (TASC) Working Groupby Charles Miller

GLOBEC International now has offspring. The baby wasborn on the 7th of April 1994 at Oslo, Norway. Its name

is the TransAtlantic Study of Calanus Working Group. InOctober it was recognized by ICES, which included TASCactivities as a function of the ICES Zooplankton ProductivityWorking Group under Heine Rune Skjoldal. Attending thebirth in Oslo were 25 scientists from Norway, Sweden,Denmark, Germany, Scotland, England, The Faroes Islands,Iceland, France, Canada and the United States. We werehosted by Stein Kaartvedt of the University of Oslo for aGLOBEC/ICES workshop designed to foster cooperation inthe study of Calanus finmarchicus all across its NorthAtlantic range from New England to Northern Norway.Convenors were Kurt Tande of the University of Tromso andmyself. Funding for the workshop came from the NorwegianResearch Council, the European Union, the U.S. GLOBECOffice, and from marine research programs of severalnations. Everyone attending is actively working on thebiology of C. finmarchicus.

In preparation for the workshop, most of the participantswrote manuscripts on a wide range of topics, includingdistribution, feeding, growth, reproductive rates, genetics,

∆∆∆

22-25 August: International Conference on Past, Present andFuture Climate, Helsinki, Finland. Contact: P. Heikinheimo,Academy of Finland, P.O. Box 57, FIN-00551, Helsinki,Finland (Phone: 358-7748-8338; FAX: 358-7748-8299;Internet: [email protected])

21-26 September: ICES Statutory Meeting: Special ThemeSession on Intermediate-Scale Physical Processes and theirInfluence on the Transport and Food Environment of Fish,Copenhagen, Denmark. Contacts: B. MacKenzie, DanishInstitute for Fisheries and Marine Research, CharlottenlundCastle, DK-2920 Charlottenlund, Denmark (Phone: +45-3396-3403; FAX: +45-3396-3434; Internet:[email protected]) OR Francisco E. Werner, University ofNorth Carolina, Chapel Hill, North Carolina 27599-3300,USA (Phone: 919-962-0269; FAX: 919-962-1254; Internet:[email protected])

24-29 September: First Global Analysis, Interpretation, andModelling (GAIM) Conference, Garmisch-Partenkirchen,Germany. Contact: D. Sahagian, GAIM Task Fore Office,Institute for the Study of Earth, Oceans, and Space, Univer-sity of New Hampshire, Durham, NH 03824 (Phone: 603-862-3875; FAX: 603-862-0188; Internet: [email protected])

5-6 October: U.S. GLOBEC Scientific Steering Committee


TASC—(Cont. from page 9)

U.S. GLOBEC NEWSU.S. GLOBEC NEWS is published by theU.S. GLOBEC Scientific Coordinating Of-fice, Department of Integrative Biology, Uni-versity of California, Berkeley, California94720-3140, telephone (510) 642-7452, FAX(510) 643-6264. Correspondence may bedirected to Hal Batchelder at the above ad-dress. Articles, contributions to the meetingcalendar, and suggestions are welcomed. Con-tributions to the meeting calendar should con-tain dates, location, contact person and tele-phone number. To subscribe to U.S. GLOBECNEWS, or to change your mailing address,please call Hal Batchelder at (510) 642-7452,or send a message to Internet [email protected], or write to theaddress above.

U.S. GLOBEC NEWS StaffHal Batchelder

Tom Powell

zooplankton during late winter andspring in sites like the Northern NorthSea and Georges Bank. However, itseems to be entirely missing from thoseregions in summer and autumn. Thus,the abundant stocks of winter-springmust be imported by advection fromoceanic areas where resting stocks atdepth maintain the species existencethrough the late summer and autumn.It was recommended as a priority thatwe work out the population budgets forseveral of these exchanges. This willallow us to distinguish between severalalternative population histories. Arethe resting stocks in oceanic sectorsstrongly dependent upon productionover the shelves? Or, are the restingstocks produced entirely in the oceanicsector and simply ‘feeding’ the shelfproduction with no strong return.

For the North Sea shelf an interac-tion between late winter inflow in theFaroes-Shetland Channel and upwardontogenetic migration of maturingCalanus have been suggested by JanBackhaus, Mike Heath, KatherineRichardson and others as a supplymechanism. That will be the subject ofan European Union Marine Science andTechnology study during early 1995.The U.S. GLOBEC Georges Bankprogram is tackling a similar problemon the west side of the Atlantic.

II. Strategies of Diapause andReproduction

The control of entry to andemergence from diapause are not wellunderstood for any species ofCalanidae. We produced severalrecommendations aimmed at producingclues about the control mechanims:

• TASC projects should select anindicator of diapause condition[gonad development, jaw facies,enzyme status] and trace itsappearance in Calanus stocks asfunction of season, temperaturehistory, depth and photoperiod.

• TASC projects should sampleresting stocks for stage composi-tion [which varies] over at leastseveral years. Basic habitat data,particularly water column tempera-ture patterns, should be recordedthrough the period prior to andduring diapause phases.

Laboratory studies were alsorecommended. Reproduction in C.finmarchicus has been a very activearea of research recently. The TASCrecommendation was that this effort besustained.

III. Population Coherence andLatitudinal Impact on GrowthPatterns

• We recommended evaluation of thediversity of the C. fimarchicusstock across its range by studies ofits molecular genetics.

• A renewed study of the growthresponse to food, temperature andother habitat factors is needed.Sophisticated data are available forrelated species, but not C.finmarchicus.

IV. Trophic Interactions andMortality

From a practical standpoint(support for our studies) we need toestablish whether interannual variabilityin fishery recruitment depends directlyupon variations of Calanus productiv-ity. It may be hard to believe that isn’testablished, but it’s not.

Mortality rates are almost alwaysunconstrained tuning variables in ourmodels of Calanus population pro-cesses. It was recommended thatTASC projects should invent and adoptstrategies for determining the partition-ing of mortality among the develop-mental stages of C. finmarchicuscohorts.

On our third and final day, wedecided to appoint ourselves as a long-term working group to continue

communication about research onCalanus finmarchicus all across itsrange. We also hope to promotecooperative studies among laboratoriesand scientists so that knowledge ofCalanus biology can increase at thefastest possible rate. We warmly inviteanyone not at the workshop to join inthis effort. We are the TransAtlanticStudies of Calanus (TASC) WorkingGroup. I am the initial chair forinterchange of information, principallythrough a newsletter. Yes, anothernewsletter. Issues No. 1 and 2 havebeen distributed to members. Copiescan be obtained by writing (use email)to me. We also have an internet maillist and internet reflector address so thatmembers can communicate rapidlywith the entire group. We hope thatwill be useful, not another source ofelectronic junk mail. (Charles Miller isProfessor of Oceanography at theCollege of Oceanic and AtmosphericSciences, Oregon State University,Corvallis, OR 97331-5503, Internet:[email protected]) ∆∆∆


ATOLL—(Cont. from page 7)

data transmission (two cameras) viafiber optics, prototype planned forOctober 1992: Distribution, large scalelong time series monitoring

ecoSCOPE (Kils): Remotely operatedor free floating vehicle, image trans-mission via fiber optics or onboardstorage, several prototypes employed inherring schools for predator preyinteraction studies. Microscalebehavior, microdistribution. See Figure2.

Optical Plankton Recorder (Kils):General purpose compact instrumentwith optional preconcentration-nets,image and data storage onboard (1-3cameras), employed since 1979 inanarctic krill studies, hand operatedfrom small working boats in schoolstudies, anchored for orientation- andecotoxicology-studies, in aquaculturefor particle-flow-studies. Mesoscalemonitoring, environmental impact onbehavior. (Until recently, Uwe Kils wasa research scientist at the Institute für

Meereskunde, Universität Kiel. Dr.Kils is now at Rutgers UniversityInstitute of Marine and CoastalSciences.)

More details of the cited instrumenta-tion are described in:

Kils U (1981) SwimmingBehaviour, Swimming Performanceand Energy Balance of Antarctic Krill,Euphausia superba. BIOMASS SciSer, 3, 1-122

Kils U (1989) On the Micro-Structure of Micro-Layers — Resultsof an in situ Zooplankton-Counter.Coun Meet Int Coun Explor Sea 1989/L15:1-4

Kils U, Ruohonen K., Mäkinen T(1991) Daily feed intake estimates forrainbow trout (Oncorhynchus mykissWahlbaum) evaluated with SONARand X-ray techniques at commercial net

cage farms. Coun Meet Int CounExplor Sea 1991/F3:1-8

Kils U (1992) The ecoSCOPE anddynIMAGE: microscale tools for insitu studies of predator prey interac-tions. Int Rev gesamten Hydrobiol (inpress)

Strickler R, Schulz P, BergstroemB, Berman M, Donoghay P, GallagerS, Haney J, Hargreaves B, Kils U,Paffenhofer G, Richman S,Vanderploeg H, Welsch W, Wethey D,Yen J (1992) Video based instrumentsfor in situ studies of zooplanktonabundance, distribution and behavior.Arch Hydrobiol (in press)

Figure 2. Image from the ecoSCOPE showing a school of juvenile herring Clupea harengus feeding in a micropatch of copepods. HerringA and B in typical s-shape shortly before attacking a copepod upwards. Herring C shortly after an attack during a u-turn. In this positionthe silvery sides produce an intense light-flash. Herring D shortly later on his downward return to his old school position. Herring Estarting a new attack upwards. Due to the deflection of light by phytoplankton and microparticles the copepods are not visible from thedistance of the optics.

∆∆∆


Introduction

As part of the U.S. Global OceanEcosystems Dynamics (U.S. GLOBEC)and the U.S. Joint Global Ocean FluxStudy (U.S. JGOFS) science programsthe National Science Foundation’s(NSF) Office of Polar Programs andDivision of Ocean Sciences announcesa call for proposals for modelingstudies related to the developingscience programs in the SouthernOcean. All proposals should besubmitted to the NSF as detailed below.

The Southern Ocean programs ofU.S. GLOBEC and U.S. JGOFS willtake place in the late 1990s. Thisannouncement is to encourage model-ing studies that will advance theunderstanding of the biogeochemistryand the interactions between marinepopulations and physical processes inSouthern Ocean ecosystems. Inparticular, modeling studies areencouraged that will advance theplanning and design ofmultidisciplinary field programs. Thegoal is to develop the capability topredict the response of oceanic bio-geochemical processes and marineanimal populations to, as well as theirinfluence upon, climatic change.

U.S. GLOBEC and U.S. JGOFShave held workshops to define scienceissues that are of importance in theSouthern Ocean. Results of theseworkshops are available in U.S.GLOBEC Report No. 5 and U.S.JGOFS Report No. 16. These docu-ments may be obtained from U.S.GLOBEC, Science Steering CommitteeCoordination Office, Department ofIntegrative Biology, University ofCalifornia, Berkeley, Berkeley, CA94720 and U.S. JGOFS Planning andCoordination Office, Woods HoleOceanographic Institution, WoodsHole, MA 02543, respectively. Inter-national plans for Southern OceanGLOBEC studies are described inGLOBEC International Report No. 5,

Announcement of Opportunity: Modeling Studies in Support of U.S.JGOFS and U.S. GLOBEC in the Southern Ocean

which is available from GLOBEC-International Secretariat, ChesapeakeBiological Laboratory, P.O. Box 38,Solomons, MD 20688. All of thesedocuments highlight modeling as animportant aspect of developingSouthern Ocean research programs anddiscuss modeling needs in light of thestated program goals.

Description

The long-range goal for the U.S.GLOBEC program is to understand theinteractions between physical processesand marine animal populations with anemphasis on predicting the effects ofglobal change on population abundanceand variability in marine ecosystems.Long-range goals for the U.S. JGOFSprogram are to evaluate and understandon a global scale the processes control-ling the fluxes of carbon and associatedbiogenic elements in the ocean and todevelop a capability to predict theresponse of oceanic biogeochemicalprocesses to climate change. TheSouthern Ocean provides an opportu-nity to combine the goals of these twoprograms to address issues of climatechange effects on biogeochemicalcycling and marine food web processesand how these interact to control andregulate biological production.

The Southern Ocean has long beenbelieved to be a region of significantbiological production globally. How-ever, it is not well understood howprimary production in the SouthernOcean is controlled. The biologicaland chemical processes suggested asregulating primary production in theSouthern Ocean range from nutrientand trace metal effects, physicalprocesses such as light and turbulentmixing, and biological interactionssuch as grazing. It’s increasinglyapparent that many of the animalpopulations in the Antarctic marinefood web have life histories that areclosely tied to the large seasonal

fluctuations in ice cover in the SouthernOcean. Hence, habitat variability ispotentially a strong control on biologi-cal production in the Southern Ocean.Full descriptions of each of these issuesand their relation to climate change aregiven in the reports listed above.

Following the recommendations ofthe national and international work-shops and those from the ScientificSteering Committees for U.S.GLOBEC and U.S. JGOFS, proposalsfor modeling studies are solicited bythis announcement in advance of fieldprograms in the Southern Ocean. It isanticipated that modeling studies willprovide guidance for the design andimplementation of the field programs,both by addressing issues of samplingstrategy, and by highlighting keyprocesses and measurements necessaryto understand the coupling amongphysical and biogeochemical processes.Modeling studies might include (butare not limited to):

• trace metal controls on primaryproduction,

• sea-ice and biological interactions,• mixed layer and biological

interactions,• biological and physical controls on

air-sea carbon exchange,• aggregation dynamics and the role

of patchiness,• top predator population dynamics

and control,• behavioral responses of predator

and prey,• paleoclimate and

paleoceanographic processes,• microbial controls on material

cycling,• coupled large and regional scale

physical-biological models, and• models as the primary tool for

historical data analysis.

In addition, studies that addressissues that will advance the state of

(Cont. on page 13)


Polar Biology and Medicine ProgramOffice of Polar Programs, Room 755National Science Foundation4201 Wilson BoulevardArlington, VA 22230

For further information contact:Dr. Polly Penhale, Polar Biology andMedicine Program, (703) 306-1033,[email protected]; or Dr. BernhardLettau, Polar Ocean and ClimateSystems, (703) 306-1033,[email protected]; or Dr. Neil Andersen,Chemical Oceanography Program,(703) 306-1587, [email protected]; orDr. Phillip Taylor, Biological Oceanog-raphy Program, (703) 306-1587,[email protected].

knowledge of modeling as well asprovide understanding of the SouthernOcean system are encouraged. Suchstudies might include ecologicalmodels for data assimilation andmanagement, and modelling techniquesfor matching scales between models.

Proposal Format

Proposals should be clearlyidentified as being in response to thisSouthern Ocean program opportunityannouncement. Requirements forproposal content and format shouldconform to the guidelines given inGrant Proposal Guide (NSF 94-2).Single copies of this document are

First Open GAIM ScienceConference

The first Global Analysis, Interpreta-tion, and Modelling (GAIM) ScienceConference of the InternationalGeosphere Biosphere Program (IGBP)will be held Sept. 24-29, 1995 inGarmisch-Partenkirchen, Germany.The Science Conference will focus onpapers in the areas of global dataanalysis and assessment, modelling ofbiogeochemical systems and theirrelationship to physical climate and

hydrologic systems, and interpretationof current trends as indicated by globaldatabases and model results forextrapolation with regard to futureglobal change. The new and continuedresearch directions which arise fromthese results should eventually lead toanswers regarding the measurement,causes and consequences of natural andanthropogenic global change factors.

Abstracts are solicited from allinterested scientists conducting relevantresearch. Abstracts are due by May 1,1995; abstract format information isavailable from the GAIM Task ForceOffice. Presentations may be in oral,poster or video poster format. Oral andposter session topics will be grouped bytime periods, including “Paleo” <20kyears), “Historical” (<2000 years),“Contemporary (<20 years), and“Future”. Morning sessions willconcentrate on measurements and dataanalysis, and afternoon sessions willfocus on modelling. There will also bea special session on Global SystemsIntegration. For further informationcontact Dr. Dork Sahagian, GAIMTask Force Office, Institute for theStudy of Earth, Oceans, and Space,University of New Hampshire,Durham, NH 03824 USA (Phone: 603-862-3875; FAX: 603-862-0188;Internet: [email protected]).

will produce an overview of thefisheries of the Okhotsk Sea, especiallyon how fishing and the environmentaffect abundance trends of walleyepollock and other non-salmonidspecies. The workshop will alsoreview the distribution and survival ofPacific salmon in the Sea of Okhotskwith particular emphasis on thesurvival, abundance and stock identifi-cation of chum salmon.

For more information about theOkhotsk Sea workshop contact thePICES Secretariat c/o Institute ofOcean Sciences, P.O. Box 6000,Sidney, BC, Canada V8L 4B2 (Phone:604-363-6366; FAX: 604-363-6827;Internet: [email protected]).

Okhotsk Sea Workshop

June 19-24, 1995, Vladivostok, Russia,is the venue for a North Pacific MarineScience Organization (PICES) work-shop on the oceanography and livingmarine resources of the Okhotsk Seaand its adjacent areas. PICES isprincipally interested in the NorthPacific Ocean and adjacent seas from30°N latitude and including the Beringand Okhotsk Seas. The purpose ofPICES is to promote and coordinatemarine scientific research in order toadvance scientific knowledge of thisarea and its living resources.

The purpose of the workshop is tobring together scientists studying orhaving interest in the Okhotsk Sea,northern Japan Sea, and Kuril Islandregion of the North Pacific. Theworkshop will review current marinescience knowledge and the availabilityand exchange of data for implementingcollaborative oceanographic researchprojects in the region. Vladivostok waschosen as the venue to maximize theopportunity for interaction betweenRussian scientists and those from othercountries. The focus of the physicaloceanography portion of the workshopwill be on circulation, sea ice and watermass modification in the Okhotsk andnorthern Japan Seas. The workshop

available at no cost from the Forms andPublications Unit, National ScienceFoundation, 4201 Wilson Boulevard,Arlington VA 22230 or via the on-lineScience and Technology InformationSystem (STIS).

Proposal Submission

Twenty completed copies should bemarked “Do not open in mail room”and sent directly to the address below.Proposals must be received at NSF byMay 1, 1995. Proposals will not beforwarded to other Programs if found tobe inappropriate for this announcement.Proposals received after the deadlinewill be returned to the senderunreviewed.

Opportunity—(Cont. from page 12)

∆∆∆

∆∆∆

∆∆∆


The 12th annual PACLIM Workshopwill be held May 2-5, 1995 at the

Asilomar Conference Center in PacificGrove, California. The workshopconsiders multidisciplinary issues ofclimate variability from weather togeological time scales with a focus onthe Pacific and western Americas. Thisyear’s theme session will be“Interdecadal Climate Variability Overthe Pacific and Western Americas.”Tim Baumgartner and Dan Cayan haveput together an exciting theme sessionwith invited keynote speakers. Most ofthe first day (May 3) will be devoted tothis theme, but the rest of the workshopwill be devoted to contributed oral andposter presentations covering the manyaspects of climate that have become thehallmark of PACLIM workshops.

The theme session will highlight:

• ocean-atmosphere variability fromthe instrumental record—naturalvariability and possible anthropo-genic change

• modelling interdecadal climatevariability in the North Pacific

• hydrological and terrestrial ecosys-tem response in western NorthAmerica

• ocean ecosystem response in theeastern North Pacific

• terrestrial and marine paleorecordsfrom the eastern Pacific andwestern North America

• societal impacts of interdecadalclimate variability,

• and more.

The informal atmosphere that hasprevailed in past workshops will bemaintained. Students are encouraged toattend and present their research. Mostoral presentations will be allottedapproximately 20 minutes. Longerinvited talks will be given in the specialkeynote theme session. Because therewill not be sufficient time for everyoneto give a talk, we ask you to considerthe poster format for highlighting yourresearch. To assure that each posterreceives attention, time will be allottedfor a 1-minute introduction for eachposter.

Lodging and meals will be providedfrom funding by several sponsors.Limited travel funds may be available,but please don’t ask for travel assis-tance unless you cannot pay your owntravel. An $80 registration fee isrequired to help defray expenses for theworkshop. Due to the constraints oflodging at the Asilomar ConferenceCenter, a maximum of about 100participants will be admitted, and youwill be expected to share a room.

For further information on the themesession contact Tim Baumgartner(Phone: 619-534-2171; FAX: 619-534-7641; Internet:[email protected]) or DanCayan (Phone: 619-534-4507; FAX:619-534-8561; Internet:[email protected]), both atScripps Institution of Oceanography,La Jolla, CA. For further informationon registration contact Don Gautier,U.S. Geological Survey, Box 25046,MS 934, Federal Center, Denver, CO80225 (Phone: 303-236-5740; FAX: 303-236-8822; Internet:[email protected]).

12th Annual PACLIM Workshop

∆∆∆

After many delays, the U.S.GLOBEC WWW site at Berkeley

has been established and is on-line.Using a web client (e.g., Mosaic,Netscape[my favorite]) access thefollowing URL:

http://www.usglobec.berkeley.edu/usglobec/globec.homepage.html

Since this site is only in its infancy, itwill continue to undergo development.To begin, the site has general info onthe U.S. GLOBEC program , completehyper-text formatted versions of themost recent U.S. GLOBEC reports #8(Optics Technology), #9 (Arabian Sea),#10 (Data Policy), and #11 (CaliforniaCurrent Science Plan; complete exceptfor Tables--which are a nightmare toformat). Also online are html versionsof U.S. GLOBEC NEWS #5 and #7.Minutes of past and agenda's ofupcoming Scientific Steering Commit-tee meetings are also available. Astime permits in the coming months, wewill attempt to "backfill" the WWWsite with some of the older (but stillrelevant) reports (specifically #6(Georges Bank IP) and #7 (EBCbackground document)), and Newslet-ters, and add forthcoming reports (LongRange Plan; Secondary ProductionWorkshop; Open Ocean Workshop).Links to both the Southern OceanGLOBEC site (at ODU) and theGeorges Bank WWW site (now atWHOI--the one at MIT is out-of-date)are provided along with links to otherOceanographic Servers.

Eventually, but not in the near future,the complete U.S. GLOBEC mailinglist may be added with a front-endsearching engine, so that addresses canbe obtained from your remote site.

Please visit our WWW site andprovide comments/criticism orfeedback to Hal Batchelder at

Berkeley U.S. GLOBECWeb Site Goes Online

[email protected]. Sugges-tions for additional info that should beavailable on-line are always welcome.Since we are new to this game, there

may be times when the material isbeing updated and you cannot connectto the server—please try again an houror so later. ∆∆∆


MEETING ANNOUNCEMENT

CLIMATE CHANGE AND CARRYING CAPACITY

(CCCC) WORKSHOP

April 19 - 20, 1995Battelle Laboratory

Seattle, WA

Workshop Sponsor: U.S. GLOBEC, NSF, NOAA

Workshop Organizers: Anne B. Hollowed and Art Kendall

The Global Ocean Ecosystem Dynamics organization (GLOBEC International) and the interna-tional North Pacific Marine Science Organization (PICES) approved an initial science plan for amulti-national research effort on Climate Change and the Carrying Capacity (CCCC) of the Sub-Arctic Pacific and coastal waters of the North Pacific and its adjacent seas. The PICES-GLOBEC, CCCC program hopes to implement programs to evaluate climate change effects onliving marine systems during the next decade.

To develop the next stage of GLOBEC research related to the CCCC program, the U.S. GLOBECprogram is sponsoring a two-day public workshop April 19-20 at Batelle Laboratory. The goal ofthis workshop will be to identify and discuss key scientific issues relevant to the CCCC programand to make recommendations for initial research activities. Interested participants are encouragedto contact the workshop organizers or Kay Goldberg of the U.S. GLOBEC Coordinating Office atthe following addresses.

Anne B. Hollowed/Art Kendall Kay GoldbergAlaska Fisheries Science Center U.S. GLOBEC SSC Coord. Office7600 Sand Point Way NE University of California, BerkeleySeattle, WA 98115 Department of Integrative BiologyPhone: 206-526-4223 Berkeley, CA 94720Internet: [email protected] Phone: 510-643-0877

Internet: [email protected]


months. Losses of deeper releases arealong shelf into the mid-Atlantic Bight,whereas surface releases are lost in thecross bank direction into slope water.The position of larvae on the southernflank of Georges Bank, both withrespect to depth in the water columnand cross-bank horizontal position,influences their subsequent fate (Figure2). With the inter-annual differences incirculation on the bank, one would

Figure 3. Distribution of stage 1 cod and haddock eggs (mean age of 2.5 days) on GeorgesBank (from the overall MARMAP data base).

_________________________________________

1 The title of the GLOBEC project is "Importance of Physical and Biological Processes to Population Regulation of Cod and Haddock onGeorges Bank: a Model-Based Study". The principal investigators are Dan Lynch (Dartmouth College), Cisco Werner (Univ. NorthCarolina), John Loder, Dave Greenberg, Peter Smith (all at the Bedford Institute of Oceanography), Greg Lough (National MarineFisheries Service (NMFS), Woods Hole), Wally Smith (NMFS, Sandy Hook), Ian Perry (Nanaimo Biological Station), and ourselves.

expect variable distributions on thesouthern flank, and thus variability inloss rate from the bank.

Simulations using the observedvertical distribution of eggs, andrealistic vertical migration behaviour oflarvae, result in considerable losses ofeggs and larvae from the bank, and arenot consistent with empirical observa-tions on larval distributions older than

(Cont. on page 17)


Georges Bank ModellingStudy

In the North Atlantic component ofU.S. GLOBEC there is an opportunityto generate consensus on whichprocesses are critical to the threeaspects of population regulation of cod,and thus to enhance our explanatorypower and predictive capability. Wewill briefly describe the approach thatour modelling team is taking and someof the results to date1. Our approach isto develop a suite of physical andbiological models using realisticgeography, forcings, and boundaryconditions for the Georges Bank codand haddock populations that capturethe processes implied under the varioushypotheses. In this way, we hope toevaluate which of the hypotheses aremore appropriate for explainingpopulation regulation processes for thisgeographic area. The results to date aredescribed in Lough et al. (1994), Lynchand Naimie (1993), Naimie et al.(1994), Lynch et al. (1992),Ridderinkhof and Loder (1994),Tremblay et al. (1994), Werner et al.(1993), and Werner et al. (1994). Herewe discuss several of the biologicalresults of significance to the conceptualliterature on marine populationregulation.

Werner et al. 1993 investigated therelative importance of circulation andbehaviour on the distribution at age ofeggs and larvae of cod and haddockthat spawn on the northeast peak ofGeorges Bank. A 3-d flow fieldcomprising the dominant M2 tidalcurrent and the seasonal-mean circula-tion associated with tidal rectification,winter-spring wind stress, and ScotianShelf inflow was used. Eggs releasedin the surface layer are rapidly advectedoff the bank, whereas a large propor-tion of eggs released at mid-depthspersist on the bank for a couple of



about 60 days. An important behav-ioral characteristic that influences on-bank retention is the depth at whichfish spawn (i.e., egg release depth).Vertical migration of the larvae doesnot influence loss rates. However, forthe model results to reflect the on-bankdisplacement of older larvae that isobserved from field studies, somehorizontal swimming behaviour isrequired. With realistic swimmingspeeds, the distribution of larvae thatswim in the on-bank direction is similarto field observations of two-month-oldlarvae.

Summary points for the first codstudy are as follows:

• During the first 60 days, circulationhas a greater influence on egg andlarval distributions than doesbehaviour.

• Vertical migration of larvae is notimportant to horizontal distribu-tion, but the mean depth of thelarvae is.

• The precise horizontal and verticallocation of older larvae on thesouthern flank is critical tosubsequent persistence on thebank.

• If the physical model is correct,some horizontal swimming isrequired for larvae to persist on thebank longer than about twomonths; or alternatively, an on-bank flow component is missingfrom the circulation model.We are presently examining the

MARMAP data on cod and haddockegg and larval distributions to betterdefine the location and time of spawn-ing, and how spawning features changeas a function of abundance. In addi-tion, we are summarizing the compositedistributions of eggs and larvae at agefor the entire eleven years of data. Theaim is to evaluate whether spawning isassociated with periods and sites ofminimal dispersal and to investigate thedegree to which density-dependentvagrancy may regulate abundance ofthese spawning populations.

The composite distribution of stage1 eggs shows interesting differences

between the location of spawning ofcod and haddock. Cod spawn morebroadly along the northern flank of thebank, whereas haddock spawning isconcentrated on the northeastern peak(Figure 3). From an analysis of thecomposite centers of mass of eggs andlarvae at, respectively, 2.5, 8, 15, 24,37, 51, and 60 days for cod andhaddock, the horizontal scales ofdisplacement with time can be summa-rized. There are differences in thecomposite distributions at age betweencod and haddock, but key similaritiesare the limited horizontal displacementover the three-month time period andthe on-bank movement of the olderlarvae (Figure 4).

Using the bimonthly circulationresults of Naimie et al. (1994), in whichseasonal baroclinic circulation isincluded with the flow components inWerner et al. (1993), the whole bankwas seeded with eggs and seasonal lossrates from different parts of the bankestimated (Figure 5). If persistence ofeggs and larvae on the bank is a “goodthing,” model results infer that theobserved time and location of spawningare about optimal. Eggs released on thenorthern flank of Georges Bank atintermediate depths during the latewinter/early spring have a highprobability of being retained on thebank for a couple of months. We arepresently modelling the loss rate ofeggs and larvae from the bank as afunction of spawning stock biomass,assuming that there is an expansion andcontraction in time and space in

spawning as a function of abundance.Lough et al. (1994) compare year-

class strengths with egg and larvaldistributions from the MARMAPdatabase. They show that some of theyears with good recruitment wereassociated with low losses of eggs andlarvae from the bank due to favourablewind conditions, and vice versa. Forexample, loss of eggs and larvae in1982 was high, there was a strong andunfavourable northeastward wind stressin April, and the year-class was weak.In contrast, in 1985 the losses wererelatively low, the winds morefavourable, and the year-class strong.Modelling work evaluated the degree towhich contrasting winds of 1982 and1985, as well as variable inflow fromthe Scotian Shelf, generated differencesin egg and larval distributions. Therewas a considerably higher loss of codeggs and larvae from Georges Bank in1982 than 1985. The results indicatethat between year differences incirculation and mixing can substantiallyimpact retention of early life-historystages on Georges Bank, and that suchprocesses contribute to variablerecruitment.

The final cod/haddock biologicalstudy completed by the team estab-lishes a modelling framework toevaluate the importance of circulationand mixing on larval feeding success(Werner et al. 1994). This study wassummarized in U.S. GLOBEC NewsNo. 7. The principal conclusions are:

• Losses of cod larvae due to

Figure 4. Center of mass of thedistribution of different egg andlarval stages of cod andhaddock on Georges Bank.Mean ages of stages 1 to 7 are2.5, 8, 15, 24, 37, 51 and 60days.

(Cont. on page 18)



starvation dominate the model atlow food densities, while at highfood concentrations the rates ofstarvation loss and advective lossare similar.

• Using estimates for late winter/early spring mean prey fields, themodel predicts insufficient foodfor larval growth on the bank. Afivefold increase in mean concen-tration of small prey is necessaryfor cod larvae to grow. Includingturbulence allows a small propor-tion of cod larvae to grow andsurvive at the initial prey concen-tration estimates.

• The region of highest retention dueto circulation processes coincideswith the region of highest growthrates, i.e., shoalward of the 60 misobath at subsurface depths of 25m or greater.These modelling results give a

flavour of one aspect of the GeorgesBank work. Overall GLOBECactivities on the bank include a broadrange of field studies on processesunderlying population regulation ofzooplankton, cod, and haddock, with anemphasis on early life-history stages.In addition, circulation is beingmonitored at key locations. Thismixture of field observations onprocesses, along with the long-termmonitoring of distributions of fish,plankton, and the oceanographicenvironment, allows the modellingactivities to focus on central problems.

Links Between GLOBEC andManagement Questions

How are the above results, and theNorth Atlantic GLOBEC program oncod, relevant to the four managementquestions posed above? In Tables 1and 2, the theoretical frameworkunderlying population regulation ofmarine species is outlined. There are anumber of competing hypotheses forthe three characteristics of populations.Reaching consensus on which of thehypotheses are more appropriate for

Figure 5. Residence time of particles on theBank from releases during 5 bi-monthlyperiods (January/February, March/April,May/June, July/August and September/October). The contours indicate the releaseareas for which particles are still on the Bankfor a specified number of days (20, 40, 60,and 80 days, respectively).

particular areas and populations is aprerequisite to providing answers thatare broadly accepted by the scientificcommunity. The circulation andmixing models are becoming suffi-ciently realistic that they can be used tohelp generate consensus.

To answer the first questionrequires a better understanding of theoceanographic processes that sustainspawning components. If the member-vagrant interpretation of pattern is morerealistic than the migration triangleinterpretation, then a different approachis needed to define geographic manage-ment units and protect individual

spawning components. The drift routeconcept involving large scale residualcurrents infers that birth site fidelity isdefined at the scale of the currentslinking spawning areas to juvenilenursery areas. In contrast, the retentionconcept infers that fidelity is defined atsmaller scales, such as re-circulationfeatures on banks, and within bays andinlets.

The approach to defining mini-mum spawning stock biomass and itsgeographical distribution variesaccording to our understanding of the

(Cont. on page 19)


control of population pattern. Thus, themodelling results indicating why codspawn in particular areas on GeorgesBank are of importance to the broaderconceptual issue of maintenance ofgeographic patterns of spawning.Practical measures such as the locationof spawning closures, the minimumspawning biomass needed for eachcomponent prior to the opening offisheries, and the time scale of recoveryof extinct components, depend onunderstanding how population patternsare regulated. Perhaps some codfisheries collapses have been due togradual elimination of spawningcomponents within a regulatoryapproach that does not consider thislevel of complexity in the biology andphysics.

Under GLOBEC, a comparativemodelling approach throughout thedistributional range of cod in the NorthAtlantic is envisioned. The increasedunderstanding of the physical/biologi-cal coupling processes that establishand maintain geographic patterns incod spawning will aid managers indealing with the first question and toimplement measures to protect thereproductive potential of the species.

The second and third questions(need for ecosystem management andimpacts of dragging) require animproved understanding on theregulation of abundance. The manage-ment implications of the two competinghypotheses for regulating abundance(Tables 1 and 2) are quite different.The match-mismatch hypothesis infersa tightly coupled community withdensity dependence operating throughfood chain interactions. Thus, onewould infer linkages between commer-cial species, and multispecies orecosystem management would beneeded. In contrast, the member-vagrant hypothesis infers relativelyuncoupled marine food chains witheach population abundance beingprimarily controlled by physicaloceanographic processes in a density-dependent manner. The populations, inessence, are interpreted to be respond-

ing independently to the physics; thus,an ecosystem management approach isnot warranted. A caveat, however,should be added for species with morecollapsed life histories such as marinemammals. Under the member-vagranthypothesis, abundance of whales, seals,and porpoises should be more influ-enced by food chain interactions than isthe case for the commercially importantfinfish.

All of the hypotheses in Table 1assume that the regulation of popula-tion features occurs in the pelagicdomain, predominantly during the earlylife-history stages. If correct, onewould not expect dramatic impacts ofdragging, which might impact foodresources for juveniles, on the abun-dance of groundfish. GLOBECresearch may clarify whether mostmanagement objectives can beachieved without taking an ecosystemapproach, and the degree to whichbenthos impacts of dragging can beignored.

There is good evidence that largescale inter-decadal climate change hasan impact on ocean productivity (seeBeamish 1994 for a North Pacificsynthesis) and on the relative abun-dance of commercially importantspecies (see Baumgartner et al. 1992for an analysis of sardine/anchovyfluctuations off California). In theNorth Atlantic, however, there isconsiderable evidence of resilience inthe biological distributions at both thecommunity and population level. Forexample, since systematic monitoringof fisheries began off northern Europein the late 19th century, some popula-tions of cod have been spawning at thesame time and locations. However,there is also evidence for dramaticchanges in dispersal and migration(Greenland, Iceland cod, Scotia Shelfhaddock, northern cod), and codavailability (eastern Scotian Shelf cod).

The GLOBEC studies on cod inthe North Atlantic should provide anunderstanding of which oceanographicprocesses contribute to the establish-ment and maintenance of populationpattern, as well as the relative abun-

dance of the different populations.From knowledge of key physicalfeatures, modelling studies will allowsome predictability of the degree towhich environmental variability limitsthe attainment of fisheries managementobjectives. To accomplish this willalso require accurate estimates ofabundance and distribution of commer-cially exploited resources.

In sum, the focus of the NorthAtlantic component of GLOBEC onpopulation regulation of cod shouldgenerate answers to some of the keyquestions that fisheries managers areasking. There is a need for increasedconsensus by the scientific communityon which of the hypotheses best capturethe critical mechanisms. The mix ofhistorical data analysis, field experi-ments, and modelling studies inGLOBEC provides us with a uniqueopportunity to make progress in acomponent of ecology that has re-mained contentious for several decades.Ecology now needs a culling ofcompeting interpretations, with aconcomitant increase in explanatorypower. (Mike Sinclair is the director ofthe Biological Sciences Branch at theBedford Institute of Oceanography inHalifax, Nova Scotia, and Fred Page isa research scientist at the Departmentof Fisheries and Oceans at the StAndrews Biological Station in NewBrunswick)

References

Baumgartner, T.R., A. Santon, and V.Ferreira-Bartrina. 1992. Reconstruction ofthe history of Pacific sardine and Northernanchovy populations over the past twomillenia from sediments of the SantaBarbara Basin, California. CalCOFI Rep.,33, 24-40.

Beamish, R.A. 1994. Climate changeand northern fish populations. Victoria,October 1992.

Cushing, D.H. 1973. The naturalregulation of fish populations. In SeaFisheries Research, p. 389-412. ed. F.R.Harden Jones, Elek Science, London.

Harden-Jones, F.R. 1968. FishMigration. Edward Arnold Ltd., London,

(Cont. on page 20)




NON-PROFIT ORGANIZATIONU.S. POSTAGE PAID

UNIVERSITY OF CALIFORNIA

University of CaliforniaU.S. GLOBEC Scientific Steering Coordinating OfficeDepartment of Integrative BiologyBerkeley, CA 94720-3140

ADDRESS CORRECTION REQUESTED

375 pp.Lasker, R. 1975. Field criteria for

survival of anchovy larvae: The relationbetween inshore chlorophyll maximumlayers and successful first feeding. Fish.Bull., 73, 453-462.

Lough, R.G., W.G. Smith, F.E.Werner, J.W. Loder, F.H. Page. C.G.Hannah, C.E. Naimie, R.I. Perry, M.M.Sinclair, and D.R. Lynch. 1994. Theinfluence of wind-driven advection on theinterannual variability in cod egg and larvaldistributions on Georges Bank: 1982 vs.1985. Int. Counc. Explor. Sea. Mar. Sci.Symp., 198, 356-378.

Lynch, D.R., and C.E. Naimie. 1993.The M

2 tide and its residual on the outer

banks of the Gulf of Maine. J. Phys.Oceanogr., 23, 2222-2253.

Lynch, D.R., F.E. Werner, D.A.Greenberg, and J.W. Loder. 1992.

Diagnostic model for baroclinic, wind-driven and tidal circulation in shallow seas.Continental Shelf Res., 12, 37-64.

Naimie, C.E., J.W. Loder, and D.R.Lynch. 1994. Seasonal variation of thethree-dimensional residual circulation onGeorges Bank. J. Geophys. Res., 99,15967-15989.

Ridderinkhof, H., and J.W. Loder.1994. Lagrangian characterization ofcirculation over submarine banks withapplication to the outer Gulf of Maine. J.Phys. Oceanogr., 24, 1184-1200.

Rothschild, B.J. and T.R. Osborn.1988. Small-scale turbulence and planktoncontact rates. J. Plankton Res., 10, 465-474.

Sinclair, M. 1988. Marine Popula-tions: an Essay on Population Regulationand Speciation. University of WashingtonPress, Seattle, 252 pp.

Sinclair, M. and T.D. Iles. 1989.

Population regulation and speciation in theoceans. J. Cons. int. Explor. Mer, 45, 165-175.

Tremblay, J.M., J.W. Loder, F.E.Werner, C.E. Naimie, F.H. Page and M.M.Sinclair. 1994. Drift of sea scallop larvaePlacopecten magellanicus on GeorgesBank: A model study of the roles of meanadvection, larval behavior and larval origin.Deep Sea Res., Part II, 41, 7-49.

Werner, F.E., F.H. Page, D.R. Lynch,J.W. Loder, R.G. Lough, R.I. Perry, D.A.Greenberg, and M.M. Sinclair. 1993.Influences of mean advection and simplebehaviour on the distribution of cod andhaddock early life stages on Georges Bank.Fish. Oceanogr., 2, 43-64.

Werner, F.E., R.I. Perry, R.G. Lough,C.E. Naimie. 1994. Trophodynamic andadvective influences on Georges Banklarval cod and haddock. Deep SeaResearch. ∆∆∆

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