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We sampled 0-group juvenile Atlantic cod Gadus morhua L. within fjords and off- shore in northern Norway from 1994 to 2008 using different gears for the 3 sampling depths: shore seine (0�3 m), pelagic trawl (various depths), and bottom trawl (>80 m). Frequencies of alleles at the Pan I locus (4218 fish analysed) showed highly significant differences among samples col- lected in the different habitats. The Pan I A allele showed a mean frequency of ~80% in the shore seine samples, 12% in the bottom trawl samples, and between 5 and 57% in the pelagic samples. These differences are thought to reflect the co-occurrence of different populations of cod in the area with different settling regimes. Shallow-water settlers are thought to represent the stationary Norwegian coastal cod (NCC), the deep-water settlers represent the migratory Arcto-Norwegian cod (ANC), and the non-settled individuals represent a variable mixture of the 2 populations. For designated samples, we analyzed 16 microsatellites (non-neutral and neutral) that supported a genetic divergence between shallow-water and deep-water settlers. Correlations between length and Pan I genotypes within selected samples showed that the Pan I BB homozygotes (typical of ANC) were significantly longer than the Pan I AA homozygotes (typical of NCC). This could reflect differences in spawning time and growth conditions between ANC and NCC, just as well as one genotype being superior to the others in terms of growth performance. Finally, we argue that the Pan I difference between 0-group NCC and ANC is not caused by contemporary selection but reflects adaptation on an ecological post-glacial time scale.

Recruitment ecology of cod has been an important focus within the framework of GLOBEC. A large part of this work focused on understanding the spatiotemporal component of cod populations. For the early pelagic life stages, studies based on an individual-based platform have provided highly valuable insights combining oceanographic, behavioural and modelling approaches. The spatial modelling of observational data often fails to include densitydependent covariates, which for early pelagic life stages, originate from the combination of circulation patterns and eggs coming from the spawning aggregations. We performed this task combining a hydrographical particle-tracking model with spatial statistical analyses to investigate the relative contribution of hydrographical variables on the spatial distribution of cod larvae in the Barents Sea under two short-term climatic regimes in the period 1986-1991. The cod larvae distribution is modelled using eggs drifting from the spawning aggregations in the Lofoten Islands. We found that inter-annual variability in the spatial aggregations of the spawners influenced the distribution of larvae drifted. We have also shown how the spatial distribution of passive-drifting larvae can change over the two regimes (1986-1988 and 1989- 1991), being more upstream in cold periods. Though the currents pattern is the main hydrographical factor shaping the spatial distribution of larvae, the temperature modifies such distribution by affecting larvae survival. However, our study highlights the geographic extension of the temperature effect changed between warm and cold periods, with clear ecological implications in terms of growth and survival. This approach can be useful for other fish populations to further understand the underlying processes shaping the seascape of early life stages. Keywords: Barents Sea cod, larvae, hydrographical particles-tracking models, spatial analyses.

The most important gadoid fish stocks of the Barents Sea spawn along the coast of Norway. The eggs, larvae and juveniles are transported northwards with the oceanic coastal currents from the spawning grounds towards their nursery and feeding areas in the Barents Sea. In this work, we present a conceptual model of the vertical dynamics of 0-group during the transport and settlement phase. Field observations of the vertical distribution and behaviour of 0-group fish recorded by a stationary acoustic system are compared to the conceptual model to validate critical assumptions. They also serve as an example of some critical observations needed to improve hydrodynamic modelling of the transport. We used two different vertical distribution algorithms for particles representing juvenile fish in a Lagrangian particletracking model. One is based on the behaviour described in the conceptual model and the other assumes random vertical distribution at a fixed depth range throughout the whole period. The distribution predicted from the vertical behaviour algorithms fits best to observations from surveys. Based on this experience we propose an observation program for collecting the needed observations to obtain a more realistic recruitment prediction model.

The fourth joint ecosystem survey was carried out during the period 8th of August to 5th of October 2006. Results of investigations 0-group, the acoustic survey for pelagic fish, main oceanographic were included in Vol.1 of Report. This volume include other materials of eco-survey 2006. and investigations have always formed a part of these surveys, and studies on plankton have been included for many years. In recent years, observations of sea mammals, seabirds, bottom fishes, and benthos have been included. Consequently, from 2003, these surveys were called ―ecosystem surveys‖. It is results from the investigations on plankton, bottom fishes, benthos and etc. A list of the participating vessels with their respective scientific crews is given in Survey report Vol.1. In addition to, the following specialists took part in preparing the Survey report vol.2: C. Hvingel (IMR), E. Orlova (PINRO),B. Bogstad (IMR),A. Dolgov (PINRO), A.Hoines (IMR).

The main aim of the ecosystem survey was to map the distribution and abundance of the young and adult stages of several demersal and pelagic fish species, and in addition to gather information about hydrographical features, zooplankton, benthos, seabirds and sea mammals. The water temperature in all observed areas was still higher (+0.7-+1.2 0C) than the long term mean but somewhat lower than in the same period 2006. The 2007 year-class of capelin and redfish are rich. 0-group of haddock, herring, eastern component of polar cod and sandeel are below average. 0-group of cod, Greenland halibut, saithe, long rough dab, wolffish and western component of polar cod were estimated to be poor. The total capelin stock was estimated to be 1.9 million tonnes, which is 2.4 times higher than last year. About 0.84 million tonnes were assumed to be maturing. However, the stock is still at a low level compared to the long term mean. The polar cod stock was estimated to be 1.2 million tonnes, which is less than last year but still higher than the long term mean. The abundance of juvenile Norwegian spring spawning herring was estimated to 1.22 million tonnes. Large parts of the numberous 2004 year-class migrated to the southeastern part of the Barents Sea, usually dominated by younger year-classes. Blue whiting of age groups 1 to 9, but mostly age 3 and 4, were observed in the western and southwestern parts of the surveyed area, and the biomass of this stock component was estimated to be 0.66 million tones, which is the third following year of decline since 2004, where the stock reached 1.4 mill. tonnes.

Long term bilateral Russian/Norwegian scientific co-operation as a basis for sustainable management of living marine resources in the Barents Sea. Proceeding of the 12th Norwegian/Russian Symposium Tromsø, 21-22 August 2007 Extended abstract (Full article included in special issue of Marine Biology Research (vol. 4, 2008), celebrating the 50 years of Norwegian-Russian research cooperation)

The third joint ecosystem survey was carried out during the period 1 super(st) of August to 5 super(th) of October 2005, This survey encompasses various surveys that previously have been carried out jointly or at national basis. Joint investigations include the 0-group survey, the acoustic survey for pelagic fish (previously known as the capelin survey), and the investigations on young Greenland Halibut north and east of Spitsbergen. Oceanographic investigations have always formed a part of these surveys, and studies on plankton have been included for many years. In recent years, observations of sea mammals, seabirds, bottom fishes, pollution and benthos have been included. Consequently, from 2003, these surveys were called "ecosystem surveys".

The main aim of the ecosystem survey was to map the distribution and abundance of the young and adult stages of several demersal and pelagic fish species, and in addition to gather information about hydrographical features, zooplankton, benthos, seabirds and sea mammals. The water temperature in all observed areas was higher (+0.5-1 °C) than the long term mean and somewhat higher than in the same period 2005. The 2006 year-class of capelin, haddock, herring, long rough dab and sandeel are rich. 0-group of eastern component of polar cod is near the average level. The 2006 cod and redfish year-class is below than average. 0-group of Greenland halibut, saithe, western component of polar cod, wolffishs and Gonatus were estimated as poor. The total capelin stock was estimated near 0.8 million tonnes, which is 2.4 times higher than last years estimate. About 0.44 million tonnes were assumed to be maturing. The polar cod stock was estimated to be 1.9 million tonnes, which is 0.14 million tonnes higher than last year, but by numbers it was two times lower then in 2005. Juvenile Norwegian spring spawning herring was estimated in the southern part of the Barents Sea to be 0.643 million tonnes. Blue whiting of age groups 1 to 14 were observed in the western and southwestern parts of the surveyed area, and the biomass of this stock component was estimated to be 0.770 million tonnes.

The main aim of the ecosystem survey was to map the distribution and abundance of the young and adult stages of several demersal and pelagic fish species, and in addition to gather information about hydrographical features, zooplankton, benthos, seabirds and sea mammals. The water temperature in all observed areas was higher (+0.5-1 degree C) than the long term mean but somewhat lower than in the same period 2004. The 2005 haddock year-class is very rich. The 2005 year-class of cod, herring, capelin and is near the average level. 0-group of the western component of polar cod is below the average level. 0-group of Greenland halibut, redfish, saithe and the eastern component of polar cod were estimated to be poor. The total capelin stock was estimated to be 0.3 million tonnes, which is 50% lesser than last years estimate. About 0.17 million tonnes were assumed to be maturing. The polar cod stock was estimated to be 1.8 million tonnes, which is 0.7 million tonnes higher then last year. Juvenile Norwegian spring spawning herring was estimated in the southern part of the Barents Sea to be 2.8 million tonnes. Blue whiting of age groups 1 to 9 were observed in the western and southwestern parts of the surveyed area, and the biomass of this stock component was estimated to be 1.1 million tonnes.

Apart from human harvest, recruitment dynamics is conceivably recognized as the main source of population variability of marine fish stocks. Factors affecting recruitment dynamics can change over both temporal and spatial scales. It follows that at the same time, over the entire range of distribution of a single population, different individuals may experience different level of environmental forcing and survival, which may not be well represented by average conditions throughout the entire distribution range. In this study we focus on the spatial pattern and its relative sources of variability in the survival of the Arcto-Norwegian cod (Gadus morhua L.) from the age-0 to the age-1 stage. This is a delicate phase of the cod pre-recruitment dynamics, as individuals are confronted with a suite of survival challenges, such as settlement, pre-winter body condition, growth, and predation avoidance. During the over 20 years analyzed (1980-2004), we found that on average age-0 cod experience lower survival in the areas north of the Norwegian coastline, from about 71 to 75 degree of latitude north and about 20 to 35 degree of longitude east. However, in coastal areas, immediately north of the Norwegian coastline, age-0 cod experience greater survival. Within the studied area, the average survival of age-0 cod is significantly greater during years with low adult cod and high capelin abundance, and high Arctic Oscillation. In addition, when capelin abundance is high, age-0 cod experience better survival particularly near the Norwegian coastline. Based on these results it appears that within the sampled grid the observed geographic patterns of age-0 cod survival is affected by the predation from adult cod in relation to the availability and distribution of capelin (Mallotus villosus), the alternative and preferred prey of adult cod. Climate can affect the spatial survival of age-0 cod by both affecting the distribution of their predators (e.g., adult cod) and the distribution and availability of zooplankton prey.

The main aim of the ecosystem survey was to map the distribution and abundance of the young and adult stages of several demersal and pelagic fish species, and in addition to this gather information about hydrographical features, zooplankton, benthos, seabirds and sea mammals. Depleted content of oxygen in the bottom layer of the southern Barents Sea that started in 1998 has continued in summer and autumn 2004. Phosphate content in the Barents Sea in summer was close to the long-term mean and reduced in autumn because of late termination of water blooming. Total abundance indices of 0-group fish were estimated by new Norwegian-Russian method used two ways. The new indices show the same richness of year classes as was found by traditional indices. Total cod numbers was estimated to be 1544 million individuals. Numbers of haddock was estimated near 791 million individuals. Assessments of other species biomass were estimated correspondingly: Redfish Sebastes marinus - 12 thousand sp., Sebastes mentella - 317 thousand sp., long rough dab - 3096 million individuals, Greenland halibut - 139 thousand sp. In addition, three species of catfish were also estimated.

These pages are rewritten, and therefore should not be considered as accurate as the original ICES CM Documents, which all can be found within the repository. Barents Sea and adjacent waters from September 1965 through September 1997

The 2nd joint ecosystem survey was carried out during the period 1st of August to 4th of October 2004. This survey encompasses various surveys that previously have been carried out jointly or at national basis. Joint investigations include the 0-group survey, the acoustic survey for pelagic fish (previously known as the capelin survey), and the investigations on young Greenland Halibut north and east of Spitsbergen. Oceanographic investigations have always formed a part of these surveys, and studies on plankton have been included for many years. In recent years, observations of sea mammals, seabirds, bottom fishes, and benthos have been included. Consequently, from 2003, these surveys were called "ecosystem surveys". The present report from the survey will cover many but not all the aspects of the survey. Main focus is on the hydrographical conditions of the Barents Sea, the results from the 0-group investigations and from the acoustic investigation on pelagic fish (capelin, young herring and polar cod). Materials on sea mammals and seabird observations are also presented in volume 1 of the report. Results from the investigations on plankton, bottom fishes and benthos will only be briefly mentioned, since the reporting of these investigations will have to await further working up of material in the laboratories. Those investigations will be included in volume 2. The 1st volume of the report was made during a meeting between scientists participating in the survey, in Kirkenes 5-8th October.

The joint ecosystem survey carried out during the period 27th of July to 2nd of October 2003 encompasses various surveys that previously have been carried out jointly or at national basis in previous years. Joint investigations include the IMR/PINRO 0-group survey and acoustic survey for pelagic fish (also known as the capelin survey). Oceanographic investigations have always formed a part of both these surveys, and in recent years, studies on plankton and sea mammals have been included. In addition, a herring survey in the western parts of the Barents Sea and parts of the Norwegian Sea, a survey for bottom fishes in the western Barents Sea and a survey for young Greenland halibut north and east of Spitsbergen were also included in the ecosystem survey. The present report from the survey will cover many but not all the aspects of the survey. Main focus is on the hydrographical conditions of the Barents Sea, the results from the 0-group investigations and from the acoustic investigation on pelagic fish. Results from the investigations on plankton, bottom fishes and sea mammals will only be briefly mentioned, since the reporting of these investigations will have to await further working up of material in the laboratories. The report was made during a meeting between scientists participating in the survey, in Murmansk 3-9th October.

The 38th annual international 0-group fish survey was carried out during the period 10 August-8 September 2002 in the Barents Sea and adjacent waters.

The 37th annual International 0-group Fish Survey was conducted during the period 10 August - 8 September 2001 in the Barents Sea and adjacent waters. Preliminary analyses of the survey data were made on board "G.O. Sars" and "AtlantNIRO" and the final report was finished by correspondence. Observations concerning the geographical distribution of 0-group fish and their abundance are given in this report together with a brief description of the hydrographical conditions in the survey area.

The thirty-fifth annual International 0-group Fish Survey was conducted during the period 13 August - 7 September 1999 in the Barents Sea and adjacent waters. Preliminary analysis of the survey data were made on board the "Johan Hjort", and the final report was finished by correspondence. Observations concerning the geographical distribution of 0-group fish and their abundance are given in this report together with a brief description of the hydrographical conditions in the survey area.

Each year in August-September joint Norwegian-Russian 0-group surveys are carried out in the Barents Sea and adjacent waters. Based on data from these surveys, the ambient temperature and salinity for several species were calculated for the Barents Sea and the Svalbard waters as well as the total area. Estimates of mean length were made for each interval in the environmental variables in order to study the variation in 0-group length with temperature and salinity. Differences within and between years in mean lengths were discussed in relation to spatial distribution and overall abundance.

The juvenile anchovy population,Engraulis encrasicolus, was studied using monthly length and weight frequency data (August1989-March 1991) from the central part of Adriatic SEa(Novigrad Sea and Karin Sea).Phisical-chemical characteristic as well as phytoplancton cell volume and tintinnines quantity were studied in connection with juvenile anchovy abundance and its influence on catch value. Space and time distribution of juvenile anchovy was inferred from catches of its 0-group anchovy from 60 purse-seine stations. Catch data obtained during the period from 1979 to 1993 were used as well. Growth of the juvenile anchovy was examined using modes and means of total lengths. Modes varied from 6.0 cm(August 1989) to 9.5 cm(March 1990) i.e. from 8.0 (July 1990) to 10.0 cm (March 1991). The means of total lengths varied from 6.7 cm(August 1989) to 10.3 (March 1990)i.e. from 7.3(July 1989) to 10.0(March 1991). Growth parameters were estimated as L =13.2 cm total length,K=0.82 per year and t0=-0.5.

Hvert år siden 1965 har de "Internasjonale O-gruppeundersøkelsene i Barentshavet og tilstøtende områder" frembrakt tallrikhetsindekser for O-gruppe fisk (årets yngel) av en rekke arter. I løpet av de 30 år toktet er blitt gjennomført har det skjedd store forbedringer i fartøy, redskap og utstyr. Tidsserien av indekser tyder på at forbedringene har medført økende fangsteffektivitet slik at sammenligningsgrunnlaget for indeksene er forrykket. I det foreliggende arbeidet er tallrikhetsindeksene blitt komgerte for økende fangsteffektivitet på to ulike måter: 1. Ved å anta at den midlere årlige fangsteffektivitet har øket proporsjonalt til økningen i midlere årlig trålåpning. 2. Ved å anta at trenden i den årlige summen av indekser for torsk, hyse og uer er en lineær funksjon av tiden og at den samme trenden også gjelder for gjennomsnittelig fangsteffektivitet. Begge korreksjonsmetodene førte til en vesentlig oppjustering av indeksene fra de tidlige årene i tidsserien.

Each year since 1965 "The International 0-group Survey in the Barents Sea and Adjacent Waters" has provided indices of abundance of 0-group fish. During the 30 years of operation of the survey large improvements in capture efficiency have been introduced including larger trawls, instrumentation for monitoring trawl depth and geometry and larger and better equipped vessels. The time series of survey indices indicate an increasing trend throughout the period and thus it seemed reasonable that the improvements have effected the level of the abundance indices. The present work is an attempt to correct the indices of abundance so that the comparability of indices from different parts of the time series is maintained. Corrections were made following two lines of approach: 1. Assuming that the annual average capture efficiency had increased proportional to the increase of the average area ofthe trawl mouth (opening). 2. Assuming that the main trend in the sum of indices of cod, haddock and redfish reflects the trend in overall capture efficiency. Both methods generated a substantial increase in the indices for the early part of the time series.

Contributors: R. Espelid, H. Græsdal, K.A. Hansen, A. Hylen, L. Kalvenes, H. Mjanger, E. Molvær, A. Raknes, Ø. Tangen, A. Hassel, J. Alvsvåg, T. Haugland, B. Hoffstad, A. Markussen, Ø. Nævdal, K. Strømsnes, B. Anthonypillai, J. Enrices, K. Gjertsen, K. Korsbrekke, M. Møgster, I. Svellingen, Ø. Torgersen

Precision and relevance of pre-recruit studies for fishery management related to fish stocks in the Barents Sea and adjacent waters. Proceeding of the sixth IMR-PINRO Symposium Bergen, 14-17 June 1994 Acoustic and biological data collected during the international O-group surveys in 1992 and 1993 were used to estimate the abundance of O-group fish of 4 species; cod, haddock, redfish and polar cod. The abundances of O-group cod amounted to 107*109a nd 84 -lo9s pecimens in 1992 and 1993 respectively. These estimates are considerably higher than those arrived at by the swept volume/area method when resonable values for trawl catch efficiencies were applied. Instantaneous mortality rates of 8-9 were calculated from the acoustic estimates of O-group in August and l-group in February for cod of the 1992 and 1993 year classes. The acoustic estimates of O-group haddock abundance amounted to 12.109 and 8-lo9 specimens and the ratio between cod and haddock abundances were significantly higher for the acoustic estimates than for the traditional indices of O-group abundance. For the two year classes under observation instantaneous mortality rates of 4-5 were arrived at from the acoustic estimates of O- and l-group haddock. For O-group redfish the acoustic estimates of abundance amounted to 38-lo9 and 48.109 specimens in 1992 and 1993 respectively. The estimates z,.rived at for O-group polar cod, 100.10~ and 62-lo9 specimens, were underestimates due to insufficient acoustic coverage of the O-group polar cod distribution area in both years.

Contributors: V. Anthonypillai, H. Hammer, J. Hamre, A. Hylen, L. Kalvenes, H. Larsen, E. Molvaer, A. Raknes, K. Strømsnes, A. Slotte, B.K. Berntsen, T.I. Halland, K. Korsbrekke, T. Mørk, J.E.Nygaard, J. de Lange, P. Fossum, H. Graesdal, S.A. Iversen, E. Meland, O. Nakken, Ø. Naevdal, R. Pedersen, A. Romslo

Contributors: Bjørn Bergflødt, Merete Fonn, Åge Fotland, Sigbjørn Mehl, Hildegunn Mjanger, Reidar Toresen, Marianne Holm, Arvid Hylen, Stein A. Iversen, Reidar Pettersen, Askjell Raknes

Rapporten er basert på en lang tidsserie med prøvetaking med strandnot av fisk og virvelløse dyr på grunt vann på Skagerrakkysten. Bortsett fra krigsåra 1940-1944 er undersøkelsene utført årlig siden 1919. På grunnlag av dette datamaterialet er det gitt en beskrivelse av alle arter av fisk som er blitt fanget i strandnot på grunt vann (maks. 15 m) på kyststrekningen mellom Torvefjorden vest for Kristiansand og Kragerø. For arter som har opptrådt i mer enn 10% av strandnottrekkene er de historiske svingningene i forekomstene beskrevet. I tillegg til fisk omfatter beskrivelsene svingninger i forekomsten av fire arter av evertebrater, svingninger i bunnvegetasjonens dekningsgrad på strandnotstasjonene, og sjøtemperaturen målt daglig på en meters djup i Flødevigen ved Arendal, gitt som årsgjennomsnitt, sommertemperatur og vintertemperatur. Rapporten gir også en beskrivelse av mulige ettervirkninger av den giftige algeoppblomstringen i Skagerrak i mai 1988, og av mulige sammenhenger mellom lave fisketettheter i en del områder og forurensning.

Contributors: Inger Marie Beck, Sigbjørn Mehl, Egil Ona, Ingvald Svellingen, Arvid Hylen, Odd Nakken, Askjell Raknes, Svein Wilhelmsen, Thor Ivar Halland, Knut Korsbrekke

Contributors: Bente Røttingen, Reidar Toresen, Sigbjørn Mehl, Gunnar Nyhammer, Rolf C. Sundt, Herman Bjørke, Arvid Hylen, Atle Totland

Since 1965 the International 0-group fish survey has been carried out in the Barents Sea during late August and early September. The main purpose is to determine the year-class strength of some commercial fish species at an early stage in their life history. The present contribution is a preliminary study on the growth of the 0-group during the first half year after spawning. Comparisons of lengths of cod, haddock, herring and capelin strongly indicate similar variations from year to year. Since these species inhabit partly the same water masses the first six months, it is likely that the variation in growth depends on some common factors. One of these may be the temperature of the environment. The results so far indicate a relationship between the growth of larvae and temperature.

Contributors: O.J. Gullaksen, K. Hansen, K.A. Hansen, T. Haugland, A. Hylen, H. Kismul, M. Møgster, T. Wickstrøm, J. Alvsvåg, B. Hoffstad, K. Lauvås, T. Mork, K. Nedreaas, Ø. Nævdal, J.E. Nygård, T.I. Halland, J.C. Holst, E. Molvær, T. Monstad, A. Romslo, E. Skoglund, 0. Tangen