London, November 2013

Transcription

1 Report from the NEAFC Working Group on Collating Information on the Distribution of All Life Stages of Blue Whiting in the North-East Atlantic and the Distribution of Catches from the Stock London, November 2013

2 Report from the NEAFC Working Group on Collating Information on the Distribution of All Life Stages of Blue Whiting in the North-East Atlantic and the Distribution of Catches from the Stock TABLE OF CONTENTS 1 INTRODUCTION METHODS Assumptions Zonal Database Catch Distributions Reported by NEAFC Contracting Parties Quality Assurance Zonal attachment problems in special zones (or grey zones) BLUE WHITING CATCHES Denmark on behalf of Faroes and Greenland EU Iceland Norway Russia Description of the fisheries BIOLOGICAL INFORMATION ON BLUE WHITING Life cycle and distribution Distribution of blue whiting in acoustic and trawl surveys CONCLUDING REMARKS REFERENCES TABLES CATCH MAPS SURVEY MAPS APPENDIX * Legend to the map on the cover page (from Payne et. al., 2012) 2

3 1 INTRODUCTION Under the Agreed Record of fisheries consultations between the European Union, the Faroe Islands, Iceland and Norway of 23 January 2013, the Coastal States noted that the NEAFC Working Group to collate information on the distribution of blue whiting in the North-East Atlantic had not yet been convened as had previously been agreed under Annex III of the Agreed Record from 22 October 2009 and endorsed by NEAFC. It was agreed by the Coastal States to recommend that this work be initiated in the first quarter of 2013 and completed by 1 October 2013 with the following Terms of Reference: TERMS OF REFERENCE FOR A NEAFC WORKING GROUP TO COLLATE INFORMATION ON THE DISTRIBUTION OF ALL LIFE STAGES OF BLUE WHITING IN THE NORTH-EAST ATLANTIC AND THE DISTRIBUTION OF CATCHES FROM THE STOCK The European Community, the Faroe Islands, Iceland, Norway and the Russian Federation agreed to recommend to NEAFC the establishment of a Working Group to collate information on the distribution of all life stages of blue whiting in the North-East Atlantic and the distribution of catches from this stock. The Working Group shall: 1. Present data on the geographical distribution of all life stages of blue whiting (biomass and abundance or their appropriate proxies versus time, where time is both age/year and quarter) by relevant s under national fisheries jurisdiction and in international waters. 2. Tabulate catch data on a monthly basis, both total and divided by country, distributed by s under national fisheries jurisdiction and beyond as precise as the data allow. Distributions shall be calculated for: a. Each of the years since fisheries started; b. Averages of the last five, ten, fifteen, twenty and thirty years both for geographic distribution (I) and fisheries (2). The Working group shall meet twice. In an initial meeting, in the first quarter of 2013, data exchange formats and working methods shall be decided. Prior to the second meeting, data shall be submitted to the Working Group by the Contracting Parties in the agreed formats. In a second meeting, data shall be compiled, cross-checked and the appropriate distributions 3

4 shall be calculated. The data compiled by the working Group shall be made available to ICES for scientific and assessment purposes. The final report shall be submitted to NEAFC by 1 October Since Norway was the host for the year s blue whiting consultations, it was decided that Norway also should chair this working group. It was also decided that this should be a meeting between relevant scientists and statisticians. Åge Høines from the Institute of Marine Research in Bergen was appointed as chair for the WG. It was impossible to hold the first meeting of the working group as planned early in the year and the first meeting was held in NEAFC headquarters in London May In this first meeting it was agreed that methodologies should remain as presented in the final report of the Tórshavn meeting in It was also agreed that the former work done in 1999 should not be revisited and that the present work should concentrate on the years after 1997, i.e. the period 1998 to present. In this first meeting it was agreed that it would not be possible to conclude the work of the Working Group by 1 October It was agreed to carry out the work on the shortest timescale considered realistic and that the next meeting of the Working Group should be held at NEAFC headquarters in London. The working group met on November 2013 with the following participants: EU Thomas Brunel Emma Hatfield Peter Hopkins Mark Payne Beatriz Roel Faroe Islands Jan Arge Jacobsen Meinhard Gaardlykke Iceland Ásta Guðmundsdóttir Norway Åge Høines (Chair) Rune Mjørlund Are Salthaug Russian Federation Evgeny Shamray 4

5 2 METHODS 2.1 Assumptions The Workshop adopted the same methodology as the Aberdeen Workshop in 1998 (Anon., 1998) and the Torshavn workshop in 1999 (Anon., 1999), and the following text is, to a large extent, copied over from the Torshavn 1999 report. However, it is amended as appropriate for the purpose of this workshop. The main changes and additions are due to the availability of advanced GIS software and the apparently higher quality of the data available. For the purpose of distributing catch to zones, catch data by ICES rectangle has been used. A database was developed at the Aberdeen and Torshavn meetings. It was assumed that input data were not available in any finer detail in spatial resolution than ICES rectangle (1 degree of longitude by half a degree of latitude), and that data were representative of the entire rectangle. Denoting a value for a landing C in the rth ICES rectangle in month m and in year y, by country i, the values tabulated were: Cˆ z, i = y= ly m lm = y= fy m= fm in which A r,z represents the proportion of the sea of rectangle r which lies within the zth EEZ, and fm, lm and fy, ly denote month and year ranges for the summation to be calculated. Then C z,i represents the total catch by country i within zone (EEZ) z. The present Working Group decided to adopt the same method as was used previously and furthermore to present the catch data in the same format as in The description of the methods to collate and present the biological data of blue whiting is presented in a separate chapter in the report (Chapter 4). r C r,y,m,i A r, z 2.2 Zonal Database For the purpose of the present workshop, a set of official national EEZs were required, as some changes in the EEZs have been made since Therefore NEAFC requested the parties to submit their official verified set of national fishery zones (EEZ) to NEAFC for the use by the present WG. When all the EEZs for the various zones were obtained, the method to allocate the proportion of a zone within each rectangle was done with GIS software. All calculations were done using Cylindrical Equal Area projection, which is assumed to produce the most correct result over a very wide geographical. The result was included in a similar database as was prepared at the Torshavn meeting to hold estimates of: The of sea in each ICES rectangle in the of interest for blue whiting; The proportion of the sea of each ICES rectangle that lies within the EEZ of each of 5

6 the contracting party, as well as in international waters outside national jurisdiction. The current method to calculate the coverage in the zonal database is considered more accurate than the estimates from the previous meetings, as some of the previous estimates (those rectangles with more than one zone in a rectangle) were done by visual inspection of charts with border lines drawn onto them. The new ZbyRect file now covers the from 35º to 84ºN and 42ºW to 69ºE. 2.3 Catch Distributions Reported by NEAFC Contracting Parties Each contracting party to NEAFC was asked to submit catch data of blue whiting by year, month and by ICES rectangle for the period 1998 to 2012 to NEAFC. Most parties reported disaggregated catch data with the exception of Poland and Estonia that gave the catch by ICES Division and year instead of ICES rectangles and month. In this case the catches were allocated to pre-agreed rectangles within each Division. This method was adopted from the previous two workshops. Hence, for most countries the data submitted were re-scaled to the official statistics by year. It was also recognized that for some countries the difference between the official figures and the figures used by the ICES-Working Group were substantial. However, official figures as a rule were used in the database. Where large discrepancies appear between the various sources of information, this is discussed below. Where official catch figures are not used, this is explained in chapter 3 about catch data for individual countries. Unallocated catches and discards (catches which cannot be attributed to individual countries) have not been considered in this analysis. 2.4 Quality Assurance Given the importance of zonal attachment to all interested parties, data need to be compiled on an equitable, fair and agreed basis using all the relevant information. Factors, which are taken into account for zonal attachment, include, inter alia, the spatial and temporal distribution of the stock and as such require that data are compiled on the most spatially and temporally resolved level. Aggregating statistical rectangle data can be used to provide a first approximation to identify catches by EEZ. However, EEZ boundaries usually bisect rectangles so that the catch by rectangle has to be apportioned across the boundary. This requires an accurate map of the EEZ (Fig ). 6

7 Some EEZs have changed since 1999 and these updates are now incorporated into the data since the WG has got the latest official coordinates of the respective EEZ from each Coastal State. Some of the most important changes are agreement between Norway and Russia in the Barents Sea, removing the former Grey Zone in this, slightly eastward change in the division between Greenland and the Fisheries Protection Zone around Svalbard, and removal of the 200 nm zone around Rockall. Still one Grey Zone exists between Faroes and UK (EU). Figure Zones in the northeast Atlantic using the official coordinates made available for NEAFC. ICES rectangles are also shown. The quality of the catch data can be seen from Table (catch information quality table). Adopted from the Torshavn 1999 meeting level 1 was defined as spatially disaggregated data 7

8 on a monthly basis and derived from logbooks. Level 2 was defined as spatially disaggregated data on a monthly basis derived from sources other than log books. Level 3 was defined as catch data, usually on an annual basis or by ICES Divisions, assigned to pre-agreed arbitrary ICES rectangles. 2.5 Zonal attachment problems in special zones (or grey zones) In some s with special s (zones or grey zones) where the EEZs from two neighbouring zones overlap each other cause problems when zonal attachment calculations were performed. Given the importance of zonal attachment, data need to be compiled on an equitable, fair and agreed basis. In the case of the special zone between Faroes and EU (Fig ) both Faroese vessels (including foreign vessels fishing on Faroese licence) and EU vessels can fish in the special (overlapping) referred to in Figure In this case it is not straightforward to allocate the catches by rectangle to zones, as the Faroese and EU vessels fish in the same rectangles but the catches are reported to two different zones. Figure (grey zone) between the Faroes and EU where both parties have right to fish. One way to solve this issue for the zonal attachment calculations is to include the zone to the catch by rectangle, i.e. to give the blue whiting catch by year and by ICES rectangle and by 8

9 month and by zone. From this it would be possible to calculate the zonal attachment from the information of the zone in the catch record itself, instead from the zonal database (as was proposed above). In the present report the special zone (grey zone) is treated as a separate zone in the zonal attachment tables and the catches are distributed to zones by respective fraction of the in each ICES rectangle. 3 BLUE WHITING CATCHES 3.1 Denmark on behalf of Faroes and Greenland Faroes Official catch statistics by zones were available from the Faroese Fishery Ministry and the Faroe Island Fisheries Inspection. Reported catches by the vessels were checked against the landing reports (weight- and sales notes). Use of logbooks is mandatory for the Faroese vessels. After 2001 the VMS system has been in regular use in the Faroese fleet and the logbook data have been checked against the VMS data since. All catches were split into rectangles by use of logbook catches, except some early mixed industrial catches within the Norwegian zone in the northern North Sea, these catches were allocated to rectangles based on the logbooks from other vessels, if available, or according to the location of the traditional industrial autumn fishery in the northern North Sea from neighbouring years. The logbook catches of blue whiting were then scaled to the official catches within each zone. This was all done within each month to ensure correct spatial and temporal amount in each square. However, for the years 1998, 1999 and 2000 the official landings are from 2 to 4 thousand tonnes higher than the submitted data. The reason is missing information from the mixed industrial fisheries in those years. Table shows a comparison of the submitted data to the NEAFC working group to the official catches and "working group data" annually submitted to ICES working groups. The difference between the official catch statistics and the submitted data to the NEAFC working group is also shown. The factor is 1.0 for all years except for the years 1998, 1999 and 2000 where the official landings are from 3 to 5 thousand tonnes higher than the submitted data. In 2000 the missing catches are from the mixed fisheries in the Norwegian zone while the source to the differences in 1998 and 1999 is unknown at the present. An update to the submitted catches will be sent to the catch data coordinator by mid December

10 Table Faroese blue whiting landings as submitted to ICES working groups (working group), Official Catch reported to ICES, and the national data as submitted to the NEAFC Workshop (submitted data). The difference between the official catch and the submitted data is shown in the last column (Official-Submitted). Year ICES WGWIDE 2013 Official catch Submitted data Difference in tonnes (official submitted data) A special issue need to be addressed concerning the fishery for blue whiting in the Faroe zone. This is the spring fishery that occurs in the southern region of the Faroese EEZ, i.e. mainly in the special (grey) zone between UK (EU) and Faroes in ICES Divisions Vb and VIa (see Fig ). Both Faroese vessels (including foreign vessels fishing on Faroese licence) and EU vessels have rights to fish in the special. Thus catches of blue whiting fished in this special zone can be reported to two different national zones pending on the origin of the vessel. 3.2 EU Denmark In Denmark first hand buyers are obliged to inform the Danish AgriFish Agency on every buying of fish and shellfish. Some of this information is, e.g. information on the amount, the catch-, the ship that has landed the fish, price, quality, size-grade etc. All this information is stored in a sales-slip database. For all vessels over a certain length the skippers are obliged to carry a logbook and in this to give information on, in which rectangle the fishery has been carried out, gear and meshes used, catches by species, etc. Information is stored in a logbook database. 10

11 The logbook information is used to distribute data by rectangle and. The landings data by rectangle are subsequently adjusted by the data in the sales-slip database. Estonia Estonia only reported catches by year and by ICES division. Catches taken in ICES-division IIa were attached to an ICES-rectangle that was 100 % in international waters in ICESdivision IIa. Catches in Vb1 were assigned to an ICES-rectangle partly in Faroese waters and partly in international waters in ICES-division Vb1. All catches were assumed to take place in April in the relevant year. France No information available for the working group. Germany No information available for the working group. Ireland The landings data are extracted from declarations made into the EC logbook scheme. Logbooks must be completed by all vessels over 10m. These data are provided by the Irish Department of Agriculture, Food and the Marine through the Integrated Fisheries Information System (IFIS) database. These data were then collated by the Irish Marine Institute into the required format. It is a legal requirement for vessels to fill in the landing declaration. The declared catches are the total catches reported by trip, vessel,, quarter and gear combination.tolerances cannot be applied to the landing declaration therefore there is a lower margin of error associated with this data. The operations catches are reported on the finer scale of ICES statistical rectangle. A tolerance level is allowed in reporting operations and therefore the figures are not as accurate as the declarations. In order to obtain catch data by statistical rectangle the operations were raised to the declarations, by means of a raising factor, calculated for each ICES division by dividing the declarations by the operations. This raising factor is then applied to operations and the final figures equal the declarations. 11

12 In the majority of years during the period the data submitted to NEAFC and the data submitted annually to ICES is the same. In three of the years there are landings reported in the declarations but not in the operations. Therefore it was not possible to allocate these landings by statistical rectangle. The Netherlands Logbook information on blue whiting catches is collected by the Directory of Fisheries in the Netherlands and a copy of the database is made available to IMARES. Dutch landing data by rectangle were provided for all the years. However, some years, part of the catch was not reported by ICES rectangle. The data not allocated to any ICES rectangle was always a very small proportion (less than 2%) of the annual catch. Given that the proportion of catches not reported by rectangle is very small, these catches were simply counted as catches not allocated to any rectangle and there was not attempt to reallocate these catches to any ICES rectangles. Table The Netherlands. Catches as listed in the stock assessment working group report (WGWIDE 2013) the official Dutch catches and the sum of the monthly catches submitted to this NEAFC working group. Differences between the official catches and the data submitted are minimal. Prior to 2006, IMARES used to estimate the amount of unreported catch (based on unofficial logbooks provided by the skippers for part of the fleet). The ICES WG catches are the sum of the declared (official) catch, the unallocated catches and the discards, and may hence deviate from the official catch. Year ICES WGWIDE 2013 Official catch 12 Submitted data Difference in tonnes (official submitted data)

13 Poland Poland only reported catches by year and by ICES division. Catches taken in ICES-division IIa were attached to an ICES-rectangle that was 100 % in international waters in ICESdivision IIa. Catches in ICES-division V after 2004 were assigned to an ICES-rectangle 100 % within EU-waters. All catches were assumed to take place in April in the relevant year. Portugal No information available for the working group. Spain No information available for the working group. United Kingdom UK (England, Wales and Northern Ireland) Blue whiting data provided by UK (E, W&NI) are extracted from logbooks and checked by the Marine Management Organisation UK (MMO) and are held by the CEFAS Laboratory, Lowestoft. These data account for all UK vessel landings into England, Wales and Northern Ireland and landings of English, Welsh and Northern Irish vessels outside the UK. It does not include any landings into Scotland or Scottish vessels landing outside the UK. Data disaggregated by month and ICES rectangle in respect of UK landings into England, Wales and Northern Ireland ports and landings of English, Welsh and Northern Irish vessels abroad were available for the period These landings represented less than 10% of the total blue whiting UK landings in years prior to More recently, England, Wales and Northern Ireland landings represented a much larger fraction of the total UK landings. ICES Working Group estimates only include 2012 for UK (England, Wales and Northern Ireland). ICES WG landings for 2012 are 1,590 tonnes, while estimated landings submitted to NEAFC are 2,866 tonnes. The discrepancy will be brought to the attention of ICES for the statistics to be updated in UK (Scotland) Blue whiting data provided by UK (Scotland) comprise all landings from UK vessels into Scotland and Scottish vessels landing abroad. These landings data are extracted from declarations made into the logbook scheme. Logbook information is held by Marine Scotland 13

14 and made available through the Fisheries Information Network (FIN) database. These data are then collated by Marine Scotland Science into the required format. The table below shows the catches as listed in the stock assessment working group report (WGWIDE 2013), the official UK (Scotland) catches and the sum of the monthly catches submitted to this NEAFC working group. The ICES WG catches are the sum of the declared (official) catch, the unallocated catches and the discards, and may hence deviate from the official catch. Differences between the official and submitted catches are minimal. Table UK (Scotland). UK(Scotland) blue whiting landings as submitted to the NEAFC Workshop (submitted data), national data as submitted to ICES working groups (ICES WGWIDE 2013), and Official Catch reported to ICES. The difference between the Official Catch and the Submitted Data is shown in the last column (Official-Submitted). All figures are in tonnes. Year ICES WGWIDE 2013 Official catch Submitted data Difference in tonnes (official submitted data) Sweden No information available for the working group. 3.3 Iceland Official catch statistics by zones are available from the Icelandic Directorate of Fisheries. Use of logbooks is mandatory for the Icelandic fleet. Reported catches are crosschecked to the landing reports (weight- and sales notes). 14

15 Catches reported to logbooks are stored as kg/haul by latitude and longitude. In the years the logbook catches represent % of the official catches. The catches were raised to the official landings figure and submitted to the working group. The catches were allocated to the ICES rectangles by months based on logbook information raised to the official catches. Table shows the submitted data to the NEAFC working group, official catches and national working group data annually submitted to ICES working group (WGWIDE). The difference between the official catch statistics and the submitted data to the NEAFC working group is also given. It is 0 all years as the submitted data was raised to the official one. There is an unexplained discrepancy in the 2004 value by ICES, as the official value of t was provided to ICES in 2005 as the Icelandic catches taken in This will be looked further into. Table Iceland. Icelandic blue whiting landings as submitted to the NEAFC Workshop (submitted data), national data as submitted to ICES working groups (working group), and Official Catch reported to ICES. The difference between the Official Catch and the Submitted Data is shown in the last column (Official-Submitted). All values are in tonnes. Year ICES WGWIDE 2013 Official catch Submitted data Difference in tonnes (official submitted data) Norway In Norway both seller (fisherman) and buyer (processing industry) are responsible for filling in correct information on the sales note for each landing. Such information is i.e. fishing, date of landing, fish species, quantities, form of presentation, size groups, value. All official Norwegian catch as reported to ICES from Norwegian authorities is based on sales notes. 15

16 The first collection and processing of sales notes data is carried out by the sales organisations, and thereafter this information is electronically transmitted to the Directorate of Fisheries, where it is further examined and later presented as the official Norwegian catch statistics by the Central Bureau of Statistics. Statistics of landings of blue whiting by ICES rectangle is available for most landings in the period since The information by ICES rectangle was converted from the national Norwegian statistical system. For most of the distribution of blue whiting the smallest square in the Norwegian statistical system corresponds exactly to the ICES rectangle system. However, in some parts of the s north of 62 N the size of the squares in the Norwegian system is either larger or smaller than the ICES rectangle. The lines defining the smallest squares, however, follow the same longitude and latitude as that of the ICES rectangle system. In the instances where the smallest square in the Norwegian statistical system consists of two or more ICES-rectangles and the corresponding ICES-rectangles are in different economic zones, information of the economic zone from the sales note is used to determine which ICES-rectangle the catch should be distributed to. The "Submitted data" and the "Official Catch" as officially reported to ICES are both based on sales notes, hence the factor is 1,0. The official data for 2012 as of November 2013 has been through a quality assurance, while the data submitted was sent before this quality assurance had taken place. This explains the difference between official data and submitted data for The catch data covers the period , i.e. the Norwegian catch data includes the last completed calendar year to provide a material as updated as possible. 16

17 Table Norway. Norwegian blue whiting landings as submitted to the NEAFC Workshop (submitted data), national data as submitted to ICES working groups (ICES WGWIDE 2013), and Official Catch reported to ICES. The difference between the Official Catch and the Submitted Data is shown in the last column (Official-Submitted). All figures are in tonnes. Year ICES WGWIDE 2013 Official catch Submitted data Difference in tonnes (official submitted data) , , , , , , , , , , , , , , ,0 3.5 Russia The Russian catch data are available by rectangle by month for the period The Submitted data are calculated from the daily reports from the Russian vessels that have been stored in a central database. Some missing information about catch positions has been dealt with by allocating the catch to specific ICES rectangles from knowledge about the fisheries in the relevant s and periods. The Official figures are from the Federal Agency on the Fisheries of the Russian Federation. The Data Submitted and the Official catches are the same for the whole reference period (see Table ). However, the ICES data in some years are not the same with Official and Submitted data because sometime official data are not available during ICES Working Group meetings. 17

18 Table Russia. Comparison of the total landings as submitted to the meeting (Submitted data), national data as submitted to ICES Working groups (Working group), and Official Catch. The difference between the Official Catch and the Submitted Data is shown in the last column (Official- Submitted). All figures are in tonnes. Year ICES WGWIDE 2013 Official catch Submitted data Difference in tonnes (official submitted data) Description of the fisheries Since 1998, 17 national fleets have been involved in the blue whiting fisheries. The highest landings have been reported by Norway, followed by the Russia, Iceland and the Faroes. Fifteen to sixteen national fleets have reported catches annually in the last decade. The distribution of catches over the whole period is shown in Figure M.1. The distribution clearly covers a wide geographic. The catches during this period can be split into two groups, a high and a low one. In the period the average catches were 1.7 million tonnes (range: million tonnes) (Table 3.6.1). Then the distribution pattern (Fig. M.2) is the same as for the whole period (Fig. M.1). In the average catches were around 0.4 million tonnes (range: million tonnes). During this period of low catches the distribution is much narrower (Fig. M.3). Figures M.19-M.30 shows the distribution by month over the whole period They mirror the migration of the fish during the year to some extent. During the first quarter the catches are taken in the west of the British Isles, on the Rockall and Hatton Banks and around the Faroe Islands. In these s generally the fishing fleet is catching on the spawning aggregations and the largest quantity is taken on these locations. In the following quarters catches are taken further north in the Norwegian Sea, the North Sea and Icelandic waters. 18

19 Minor seasonal difference is seen in the catches from the southern off Spain and Portugal. Catches from this are taken at a relatively stable level during the whole year (Figs. M.1 M.30). Most of the catches are taken in the directed pelagic trawl fishery in the spawning and post spawning s (Divisions Vb, VIa, b, XII and VIIb, c (Figs , M.1 M.30)). Catches are also taken in the directed and mixed fishery in Sub IV and Division IIIa, and in the pelagic trawl fishery in the Subs I and II and in Divisions Va and XIVb. These fisheries in the northern s have taken between t per year in the last decade, while catches in the southern s (Sub VIII, IX, X, Divisions VIId, e and g k) have been in the range of t. The proportion of landings originating from the Norwegian Sea fluctuates greatly, having increased from 5% of the total in the mid-1990s to around 30% in , after which it decreased again to below 10%. These fluctuations are thought to be linked, among other things, to fluctuations in recruitment. In Division IXa blue whiting is mainly taken as bycatch in mixed trawl fisheries (ICES, 2008a). The proportions of landings originating in each are mapped and presented in the annual ICES working group reports. Figure ICES Statistical s. 19

20 The seasonal distributions of catches have changed consistently during the whole period, (Fig , Figs. M.19 M.30). In the start of the period the majority of the catches were taken in April-May, but the peak catch time has gradually moved towards the start of the year. In recent years the main fishery has been conducted in March-April. Another trend is a gradual decrease in the proportion taken in the latter half of the year; in the earlier years this proportion was much larger. However, the period is an exception when a high proportion of the catch was taken in quarters 3 and Relative catch (%) Month Figure Relative catch by month of blue whiting in the period In Tables the annual catches of blue whiting are given, in tonnes and by percentages by zones. The distribution of catches by zones was based on information on catches by ICES rectangles. In cases where ICES rectangles bisected economic zones the allocation of catches to different zones was calculated on the basis of the proportion of each rectangle within the zones. This may cause some bias in the zonal catches but is considered to be small. It should be noted that the catch in the various zones may have been influenced by factors like setting a management plan, agreement on sharing the TAC and various agreements between nations of mutual access for fishing in each other s national zones. However, by far the highest proportion of the catches is taken within the EEZ of EU through the years (Table 3.6.3). Next in line are the Faroes and the International West. 20

21 Figure Relative distribution of catch by zone (left axis) and total catch (right axis) in the period BIOLOGICAL INFORMATION ON BLUE WHITING 4.1 Life cycle and distribution Blue whiting (Micromesistius poutassou) is widely distributed in the Northeast Atlantic, from the Gulf of Cadiz to Svalbard and into the Barents Sea, between southeast Greenland and the Kola Peninsula (Bailey, 1982; Zilanov, 1984; Monstad, 1990). The vast majority of the spawning takes place between March and April, along the shelf edge and the banks west of the British Isles. Spawning is also found to take place in several local s, such as the Norwegian coast, in the Faroese and Icelandic waters, in the Bay of Biscay and further south along the Iberian shelf edge. Spawning takes place at depths between 300 and 600 m and the spawning period is from January to June, starting in the south and ending in the north. The eggs and larvae spawned on the Porcupine Bank (west of Ireland) can drift both towards the south and towards the north, depending on the spawning location, oceanographic conditions and the effects from wind force, while the spawning products from the northern spawning west of the Hebrides always drift northwards. The northward drift spreads the major part of the juvenile blue whiting to the Norwegian Sea and adjacent s from Iceland, the Faroes and North Sea to the Barents Sea. The larvae usually settle on the deeper of the various shelf-edges in the autumn and stay more or less associated with the bottom the first winter or more, gradually becoming part of the mature stock after 2 or 3 years. The southwards drifting larvae end up as juveniles in the Bay of Biscay and along the Iberian Peninsula. 21

22 Juveniles are distributed widely, from the Iberian Peninsula in the south, north to the Barents Sea and west to the Irminger Sea. In times of high abundance the Norwegian Sea is considered to be an important nursery. Then they are also found in great amount in the adjacent waters, like the Barents Sea and the Icelandic waters. Adult blue whiting carry out active feeding and spawning migrations. Late autumn/early winter mature blue whiting congregates in the slope north and east of the Faroes. From here they start the spawning migrations southwards to the bank and shelf edge west of the British Isles. After spawning the feeding migrations start, either to the north or the south. Morphological, physiological, and genetic research has suggested that there may be several components of the stock which mix in the spawning west of the British Isles. However, in the assessments, blue whiting is treated as a single stock. Due to the large population size, its considerable migratory capabilities and wide spatial distribution, the stock composition and dynamics require continued monitoring. The migration routes of blue whiting in the north Atlantic are shown in Figure

23 Figure Migration routes for the blue whiting in the Northern Atlantic. (Source: Worsoe Clausen, et al., 2005) 4.2 Distribution of blue whiting in acoustic and trawl surveys The geographical distribution of the blue whiting stock is wide, ranging from Gibraltar to the Svalbard islands. There are no surveys that cover the entire population at the same time, but many surveys that cover parts of the stock. However, there are two important international acoustic surveys carried out that target different components of the blue whiting stock. One is the blue whiting spawning stock survey (IBWSS) carried out in March-April on the spawning grounds west of the British Isles and covers the main spawning of the stock. The other one is the ecosystem survey in the Nordic Seas (IESNS). This survey was designed to target the feeding migration of the NSSH but also targets other pelagic species such as blue whiting and mackerel. This survey covers important nursery s of blue whiting in the Norwegian 23

24 Sea but is too early to adequately cover the blue whiting post-spawning migration. Estimates of biomass proportions in the different zones are only made for these two surveys. It should, however, again be noted that blue whiting occurs in significant quantities outside these survey s, for example along the south-western European shelf edge. There are many other surveys not targeting blue whiting but where the species is caught incidentally, making it possible to obtain (local) abundance estimates. A description of the two main surveys (IBWSS and IESNS) and other surveys is given below Main surveys Blue whiting spawning stock survey (IBWSS) Acoustic surveys have been carried out in March-April on the main spawning grounds west of the British Isles since the early 1980s. From 2004 onwards the spawning stock survey has been internationally coordinated (International blue whiting spawning stock survey, IBWSS). Before 2004, Norway and Russia conducted such spawning stock surveys independently. Estimates of blue whiting biomass per rectangles of 1º latitude 2º longitude are available from the Norwegian survey in the period and from the international survey after The latter biomass estimates are also used in the ICES stock assessment of blue whiting. In order to obtain biomass estimates per ICES rectangle (0.5º latitude 1º longitude) it was assumed that the biomass was evenly distributed within the larger squares. The resulting spatial biomass distributions are shown in Figures M.31 M.46. Percentage of estimated blue whiting biomass and average proportions per EEZ are shown in Table and respectively. Due to these tables then by far the most of the spawning stock is within EU waters 70-90%, in Faroes waters 5-21% and in the International west zone 0-21% at spawning time. In the proportion of biomass in the Faroes and in the International west zone was swapped compared to earlier years. After 2008 the proportion in the International west zone decreased substantially and this is congruent with the strong decreasing trend in the total stock biomass. It should be pointed out, however, that there is very limited or no coverage of other s where blue whiting is known to spawn. This includes partially the Faroese-, Icelandic and Norwegian EEZs. Also, judging from the distribution figures, it may be questionable whether the zero-line of the blue whiting distribution was obtained in all years. International ecosystem survey in the Nordic Seas (IESNS) An internationally coordinated acoustic survey has been carried out in the Norwegian Sea in April-May since Prior to 2004 only s in the Norwegian Sea outside the Icelandic EEZ were covered. In 2004 and 2005 the Icelandic zone off East- and southeast Iceland was partly covered and in 2006 and later years the Icelandic surveys included the shelf s off west- and south Iceland as well as s in the western and southwestern Norwegian Sea in the Icelandic. In the years Iceland conducted summer surveys targeting herring and blue whiting in July-August off West-, South-, and East Iceland which were discontinued after the IESNS surveys in Icelandic waters were extended to include s to 24

25 the west and south of Iceland (see below). Blue whiting has been one of the target species in the IESNS survey since The eastern part of the Norwegian Sea is assumed to be an important nursery for blue whiting and the samples are dominated by immature fish, especially in years when strong recruitment occurs. Estimates of blue whiting biomass per rectangles of 1º latitude 2º longitude are available from 2000 onwards, given the shortcomings of the coverage. In order to obtain biomass estimates per ICES rectangle (0.5º latitude 1º longitude) it was assumed that the biomass was evenly distributed within the larger squares. The resulting spatial biomass distributions are shown in Figures M.47 M.60. Percentage of estimated blue whiting biomass and average proportions per EEZ are shown in Table and respectively. These tables show that most of the biomass is inside the EEZ of Norway (29-66%), Faroes (7-48%) and Iceland (5-25%) and less in other EEZs. The main disadvantage of this survey series is the coverage Other surveys Blue whiting acoustic surveys in Icelandic waters in July-August Iceland conducted targeted surveys for blue whiting in Icelandic waters in July-August in the period Estimates of blue whiting biomass per ICES rectangle are available from this survey (Figs. M.61 M.67). The surveyed varied somewhat between years and the total distribution of blue whiting in this was not covered. Areas off West- and Northeast-Iceland received poorer coverage in general than South- and Southeast Iceland but in all years the off the slope of Southeast - and East Iceland was covered. Despite these shortcomings the conclusion can be drawn that the stock has a wider distribution in s to the west, south, east and north-east of Iceland in years of high abundance. In general young fish are distributed off and along the slope at SE-, S- and SW-Iceland. The older age groups in general are more common off the slope of E-Iceland and with a distribution extending further north as well as further offshore in that. Norwegian bottom trawl survey in the Barents Sea Norway has conducted a bottom trawl survey in January-March targeting cod and other demersal fish in the Barents Sea since late 1970s. Blue whiting are regularly caught as a bycatch species in this survey. Swept estimates of blue whiting biomass per ICES rectangle are available from 1998 onwards (Figs. M.68 M.83). Joint Norwegian/Russian ecosystem survey in the Barents Sea Russia and Norway have carried out a joint ecosystem survey in August-September since Acoustic estimates of blue whiting biomass per rectangles of 1º latitude 2º longitude are available from 2005 onwards. In order to obtain biomass estimates per ICES rectangle (0.5º latitude 1º longitude) it was assumed that the biomass was evenly distributed within the larger squares. The resulting spatial biomass distributions are shown in Figures M.84 M

26 Russian trawl-acoustic survey of main demersal fish species in the Barents Sea In October-December PINRO carried out a trawl-acoustic survey of main demersal fish species in the Barents Sea. Standard trawl positions during the survey are shown in Figure Blue whiting distribution in the Barents Sea, their abundance and biomass were also estimated acoustically. Estimates of blue whiting biomass per ICES rectangle are available from this survey (Figs. M.94 M.107). Icelandic bottom trawl surveys (SMB and SMH) The Icelandic bottom trawl surveys in spring (SMB) and autumn (SMH), targeting cod and other demersal species, have been conducted since 1985 and 1995 respectively. The trawl stations are fixed. Blue whiting is caught as a bycatch in these surveys. All age-groups are represented in the catches. In autumn the catch rate of blue whiting is much higher than in spring. This is in accordance with the observed northwards feeding migrations of the blue whiting stock after spawning earlier in the year and a return spawning migration in October- February. The topography of the survey makes sensible stratification difficult. As the trawl stations are fixed an index based on catch rate alone is considered more representative than a swept index. Faroes bottom trawl surveys On the Faroe plateau two annual demersal bottom trawl surveys are carried out by the Faroese Marine Research Institute (FAMRI), one during spring (FO-GFS-Q1) from March 1996 to present and one during late summer/early autumn (FO-GFS-Q3) from August 1994 to present. The surveys have not been used in the blue whiting assessments. The surveys are aimed at cod, haddock and saithe, but varying amounts of blue whiting are caught as by-catch especially in the deeper regions of the shelf. The size of the blue whiting ranges from cm. After the spawning in early spring the larvae drift northwards with the currents and young of the year are found in the deeper regions of the shelf in the autumn. Also 1-group blue whiting are found on the shelf in the same regions and are caught in the spring ground fish survey. The average catches of blue whiting per unit effort (kg/hour) by ICES rectangle for the spring (Fig. M.108) and summer (Fig. M.109) bottom trawl surveys are available from 1998 and onwards. Norwegian shrimp survey in Skagerrak - Norwegian Deep Norway has carried out a bottom trawl survey targeting shrimp (Pandalus borealis) since Before 2005 the survey was conducted in October-November, during it was carried out in May and from 2007 onwards it was conducted in January-February. Swept estimates of blue whiting biomass are available from 1998 onwards (Figs. M.110 M.125). Scottish IBTS surveys Scotland (Marine Scotland Science) conducts five bottom trawl surveys each year (Table 4.2.5), most of which are part of the co-ordinated ICES International Bottom Trawl Survey series (the exception is the Rockall survey). 26

27 All five surveys use the GOV net (Grande Ouverture Verticale). The ground gear differs. The west coast and Rockall surveys use one type of ground gear, to deal with the rough ground in those s. The North Sea surveys use a less robust ground gear. Figures M.126 to M.130 show values of mean numbers of blue whiting caught per 1 hour tow (including zero values) per ICES statistical rectangle in the Scottish surveys. Celtic Sea and Western approaches groundfish survey (WCGFS) An autumn West Coast groundfish bottom trawl survey was carried out annually by MAFF/Defra since 1979 until The fishing gear used was a modified Portuguese High- Headline trawl (PHHT). Since 1993, a standard survey covering the whole of ICES Divisions VIIa and f has been undertaken, with additional tows in the north-east of ICES Division VIIg surveyed when time allowed. Catch data of blue whiting per hour tow (including zero values) per ICES rectangle are available from 1998, and the averages of these over the period are shown in Figure M.131. Surveys for this period were conducted in the 1 st quarter. International Bottom Trawl survey in the North Sea The International bottom trawl survey (IBTS) series in quarter 3 is co-ordinated by the International Council for the Exploration of the Sea (ICES). The gear used is the GOV. Catch per unit effort for blue whiting by ICES rectangle are plotted in Figure M.132 based on the data collected by Centre for Environment, Fisheries and Aquaculture Science (Cefas). Data were averaged for the period 1998 to date; tows with zero values were included. 27

28 Table List of surveys for which abundance estimates of blue whiting are available per ICES rectangle. Acronym Name Period Time of year Method used IBWSS International blue whiting March-April Acoustic spawning stock survey 2013 IESNS International ecosystem April-June Acoustic survey in the Nordic Seas 2013 ICEAC Blue whiting acoustic surveys July-August Acoustic in Icelandic waters 2004 BARWINS Norwegian bottom trawl survey in the Barents Sea January-March Bottom trawl BARAUTA Joint Norwegian/Russian August- Acoustic ecosystem survey in the 2013 September Barents Sea BARRUS SHRIMPS WCGFS IBTSQ1 IBTSQ3 FO-GFS-Q3 Russian trawl-acoustic survey of main demersal fish species in the Barents Sea Norwegian shrimp survey in Skagerrak - Norwegian Deep Celtic Sea and Western approaches groundfish survey International Bottom Trawl Survey in the North Sea International Bottom Trawl Survey in the North Sea West of Scotland bottom trawl survey West of Scotland bottom trawl survey October- December Variable 1st quarter February-March Rockall bottom trawl survey National bottom trawl survey on the Faroe Plateau 2013 National bottom trawl survey on the Faroe Plateau 2013 January- February Autumn UK-SCO-Q1- SWC UK-SCO-Q4- SWC UK-SCO-Q3- Rock FO-GFS-Q1 November- December September Spring Summer Bottom trawl/acoustic Bottom trawl Bottom trawl Bottom trawl Bottom trawl Bottom trawl Bottom trawl Bottom trawl Bottom trawl Bottom trawl 28

29 Core or peripheral s? Identifying regions that are core to a distribution of a stock and those that are peripheral can provide valuable information. An attempt was made to identify such s by using data from the surveys in Table These results clearly identify the Barents Sea as a peripheral region for the blue whiting stock in the North Atlantic. Both the autumn and winter surveys, performed in August and February respectively, show increases in the relative proportion of the stock as the abundance of the stock increases. This suggests a density-dependent distribution effect in this region. However, other mechanisms may also be at play: Heino et al. (2008) also highlight the effect of warming and the inflow of Atlantic waters in this region. However, these authors did not explicitly test for density-dependent effects. Competition from other species (e.g. herring) could also be important. Larval distribution The NEAFC working group also considered the distribution of the earliest stages of blue whiting. Appropriate data regarding the distribution of these life stages is generally difficult to obtain, particularly as blue whiting spawn over a large spatial domain. Data regarding the distribution of eggs is essentially absent. However, blue whiting larvae are one of the most commonly captured forms of ichthyoplankton (Corten and Lindley, 2003) in the Continuous Plankton Recorder (CPR) survey (Richardson et al., 2006). Analysis of the data on CPR blue whiting larval distribution covering the to the west of the British Isles show two centres of high spawning density. One centre occurs over the Rockall trough whilst the other appears in the Porcupine Seabight. The northern centre is in good agreement with the distribution of the spawning aggregations as observed during the IBWSS. However, the high density centre in the Porcupine Seabight has not been independently observed before, as it is to the south the region typically covered by the IBWSS. 29

30 Figure Annually integrated spatial larval density from the CPR. Isobaths are draw at 200 m (thin line) and 1000 m (thicker line) depths for reference. 5 CONCLUDING REMARKS The proportion of the total stock that occurs in a given at a given time of the year is expected to vary between years. Changes in the absolute abundance of the stock can lead to expansion and/or contraction of its spatial distribution, both in relative and absolute terms. The spawning stock of blue whiting has displayed substantial changes in its abundance during the 30 years that it has been assessed, ranging between 2 and 7 million tonnes, and the effect of population density on spatial distribution can also be expected to have changed substantially during this time. Additionally, both climate variability (e.g. sub-polar gyre dynamics) and directional climate change have had substantial impacts on the marine environment in the North Atlantic in the last few decades: the relative quality of the habitats occupied by blue whiting are therefore expected to have varied, and could also potentially drive distributional changes. Furthermore, competition from other species (e.g. herring, mackerel) can also be potentially important, and may also drive changes in distribution: the abundance of these species in the North Atlantic has also changed dramatically during the last decades. Given these multiple mechanisms that can drive expansion and contraction, and as changes in distribution have been observed in other pelagic fish stocks in this region (e.g. mackerel, Norwegian spring-spawning herring), it therefore seems unlikely that the distribution of blue whiting would remain constant. In this report catches in the years have been compiled by years, months, ICES squares and EEZs. Spatial distribution maps have been made by using these data. It is clear that these maps cannot be directly used as evidence for blue whiting biomass distribution as 30

31 catch data depend on a number of factors that influence fleets behavior such as agreements for quota allocation, access to national EEZs, market prices, availability of other pelagic stocks, etc. The results from a range of different surveys have also been collated and analyzed in this report. The blue whiting stock is distributed over a vast and there are no surveys that cover the whole population at the same time. There are however many surveys that cover parts of the stock, but the equipment and methods used in each survey often differs making it impossible to add them to a total biomass distribution result. The surveys show only the distribution of the stock at the time they are conducted and results from each survey can only be compared to its earlier year s result. Unfortunately no survey information from the southern (Bay of Biscay and the Iberian Peninsula) was available for the working group. Due to these problems it was impossible for the working group to address fully the ToR 1 (concerning fisheries independent data) and tabulate proportions of blue whiting biomass at all life stages on zones. It could only be done for the spawning stock as the surveys on the spawning grounds in March-April (IBWSS) are considered to cover the bulk of the spawning stock at the spawning time. Based on the IBWSS results around 80% of the blue whiting spawning stock is within EU waters and 12% within Faroes EEZ at that time. However, it should still be noted that spawning also occurs in coastal s and fiords which are not covered by the survey (Anon, 1999). One solution for answering questions like this (i.e. dividing biomass by zones), for a stock with this very wide distribution, is to standardize the survey methodology on each geographical survey or initiate a huge international survey effort covering the whole known distribution (e.g. effort in line with the mackerel egg survey covering the full distribution using the same methodology as in the IESNS). The working group has compiled and systematized the available data from different surveys on the distribution of the blue whiting stock and the catch statistics from the fishery. Although much of the survey data is not designed to cover the total stock, and the catch data often are results of quota and access agreement, the working group is of the opinion that overall the report gives a relevant general picture of the temporal and spatial (zonal) distribution of the blue whiting stock in the period , even though it can t be quantified in proportion of biomass per zone. 31

32 REFERENCES Anon Report of the NEAFC workshop on mackerel and blue whiting Aberdeen, June pp. Anon Report of the NEAFC workshop on mackerel and blue whiting Tórshavn, February pp. Bailey, R.S., (1982). The population biology of blue whiting in the North Atlantic. Advances in Marine Biology, 19: pp Corten, A, and Lindley, J The use of CPR data in fisheries research. Progress in Oceanography, 58: Heino, M., Engelhard, G. H., and Godø, O. R Migrations and hydrography determine the abundance fluctuations of blue whiting (Micromesistius poutassou) in the Barents Sea. Fisheries Oceanography, 17: Monstad, T Distribution and growth of blue whiting in the north-east Atlantic. ICES CM. 1990/H14, 47 pp. Payne, M.R., Egan, A., Fässler,S.M.M., Hátún, H., Holst, J.C., Jacobsen, J.A., Slotte, A. and Loeng, H The rise and fall of the NE Atlantic blue whiting (Micromesistius poutassou), Marine Biology Research, 8:5-6, , DOI: / Richardson, A.J., Walne, A.W., John, A.W.G., Jonas, T.D., Lindley, J.A., Sims, D.W., Stevens, D., Witt, M Using continuous plankton recorder data. Progress In Oceanography, 68: Worsøe Clausen, L., Power, G., Timoshenko, N. and Tangen, O. (2005) Report of the Blue Whiting Otolith Ageing Workshop. ICES Planning Group on Commercial Catch, Discards and Biological Sampling (PGCCDBS). Co-sponsored by the Commission Regulation (EC) No 1639/2001 Zilanov, V.K., Biology and fishery of blue whiting in the Northeast Atlantic (in Russian). Pischevaya promyshlennost, Moscov

33 TABLES 33

34 Table Blue whiting catches - data availability and quality as used in the present Workshop report and in the database file Year DEU DNK ESP EST FRA FRO GRL IRL ISL NLD NOR POL PRT RUS SWE UKS UK (E, W, NI) = spatially disaggregated data (rectangles) on a monthly basis and derived from logbooks spatially disaggregated data (rectangles) on a monthly basis and derived from sources other 2= than logbooks 3= catch data, usually on an annual basis, assigned to arbitrary ICES rectangles NA= no data available, but fishery - = data on fishery in relevant year, no information about data quality 34

35 Table Catches (tonnes) of blue whiting by zones for each year Year EU Norway Iceland Svalbard Jan Mayen Green-land Faroes 35 EU/FO west Bar. Sea Norw. Sea Russia Bar.Sea Total

36 Table Catches (percentages) of blue whiting by zones for each year Year EU Norway Iceland Svalbard Jan Mayen Green-land Faroes 36 EU/FO west Bar. Sea Norw. Sea Russia Bar.Sea Total

37 Table Average percentage of catches by zone for the last 5, 10, 15, 20 and 30 years EU Norway Iceland Svalbard Jan Mayen Faroes EU/FO west Bar. Sea Norw. Sea Average Average Average Average Average Russia Bar.Sea Table Average percentage of catches by zone in and EU Norway Iceland Svalbard Jan Mayen Greenland Greenland Faroes EU/FO west Bar. Sea Norw. Sea Average Average These two periods are before and after the coastal states came to a quota agreement Russia Bar.Sea 37

38 Table Percentages of blue whiting biomass by zones (IBWSS) Not covered Table Average percentage of blue whiting biomass by zones (IBWSS) for the last 5, 10 and 16 years Jan Mayen Year EU Norway Iceland* Svalbard Jan Mayen Greenland Faroes EU/FO west Bar. Sea Norw. Sea Russia Bar.Sea Total Greenland EU/FO west Bar. Sea EU Norway Iceland Svalbard Faroes Russia Average Average Average Norw. Sea Bar.Sea 38

39 Table Percentages of blue whiting biomass by zones (IESNS) Not covered Table Average percentage of blue whiting biomass by zones (IESNS) for the last 5, 10 and 14 years Jan Mayen Year EU Norway Iceland Svalbard Jan Mayen Greenland Faroes EU/FO west Bar. Sea Norw. Sea Russia Bar.Sea Total Greenland EU/FO west Bar. Sea EU Norway Iceland Svalbard Faroes Russia Average Average Average Norw. Sea Bar.Sea 39

40 CATCH MAPS Figure M.1. Summarized total catch by ICES rectangle over the period

41 Figure M.2. Summarized total catch by ICES rectangle over the period

42 Figure M.3. Summarized total catch by ICES rectangle over the period

43 Figure M.4. Summarized total catch by ICES rectangle in Figure M.5. Summarized total catch by ICES rectangle in

44 Figure M.6. Summarized total catch by ICES rectangle in Figure M.7. Summarized total catch by ICES rectangle in

45 Figure M.8. Summarized total catch by ICES rectangle in Figure M.9. Summarized total catch by ICES rectangle in

46 Figure M.10. Summarized total catch by ICES rectangle in Figure M.11. Summarized total catch by ICES rectangle in

47 Figure M.12. Summarized total catch by ICES rectangle in Figure M.13. Summarized total catch by ICES rectangle in

48 Figure M.14. Summarized total catch by ICES rectangle in Figure M.15. Summarized total catch by ICES rectangle in

49 Figure M.16. Summarized total catch by ICES rectangle in Figure M.17. Summarized total catch by ICES rectangle in

50 Figure M.18. Summarized total catch by ICES rectangle in

51 Figure M.19. Summarized total catch by ICES rectangle in January. Figure M.20. Summarized total catch by ICES rectangle in February. 51

52 Figure M.21. Summarized total catch by ICES rectangle in March. Figure M.22. Summarized total catch by ICES rectangle in April. 52

53 Figure M.23. Summarized total catch by ICES rectangle in May. Figure M.24. Summarized total catch by ICES rectangle in June. 53

54 Figure M.25. Summarized total catch by ICES rectangle in July. Figure M.26. Summarized total catch by ICES rectangle in August. 54

55 Figure M.27. Summarized total catch by ICES rectangle in September. Figure M.28. Summarized total catch by ICES rectangle in October. 55

56 Figure M.29. Summarized total catch by ICES rectangle in November. Figure M.30. Summarized total catch by ICES rectangle in December. 56

57 SURVEY MAPS International Blue Whiting Spawning Stock Survey, March April (IBWSS) (survey tracks in red, only visible if no fish were recorded) Figure M.31. IBWSS. Estimated total biomass by ICES rectangle in Figure M.32. IBWSS. Estimated total biomass by ICES rectangle in

58 Figure M.33. IBWSS. Estimated total biomass by ICES rectangle in Figure M.34. IBWSS. Estimated total biomass by ICES rectangle in

59 Figure M.35. IBWSS. Estimated total biomass by ICES rectangle in Figure M.36. IBWSS. Estimated total biomass by ICES rectangle in

60 Figure M.37. IBWSS. Estimated total biomass by ICES rectangle in Figure M.38. IBWSS. Estimated total biomass by ICES rectangle in

61 Figure M.39. IBWSS. Estimated total biomass by ICES rectangle in Figure M.40. IBWSS. Estimated total biomass by ICES rectangle in

62 Figure M.41. IBWSS. Estimated total biomass by ICES rectangle in Figure M.42. IBWSS. Estimated total biomass by ICES rectangle in

63 Figure M.43. IBWSS. Estimated total biomass by ICES rectangle in Figure M.44. IBWSS. Estimated total biomass by ICES rectangle in

64 Figure M.45. IBWSS. Estimated total biomass by ICES rectangle in Figure M.46. IBWSS. Estimated total biomass by ICES rectangle in

65 International Ecosystem Survey in the Nordic Seas, May (IESNS) (survey tracks in red (available only from 2007), only visible if no fish were recorded) Figure M.47. IESNS. Estimated total biomass by ICES rectangle in Figure M.48. IESNS. Estimated total biomass by ICES rectangle in

66 Figure M.49. IESNS. Estimated total biomass by ICES rectangle in Figure M.50. IESNS. Estimated total biomass by ICES rectangle in

67 Figure M.51. IESNS. Estimated total biomass by ICES rectangle in Figure M.52. IESNS. Estimated total biomass by ICES rectangle in

68 Figure M.53. IESNS. Estimated total biomass by ICES rectangle in Figure M.54. IESNS. Estimated total biomass by ICES rectangle in

69 Figure M.55. IESNS. Estimated total biomass by ICES rectangle in Figure M.56. IESNS. Estimated total biomass by ICES rectangle in

70 Figure M.57. IESNS. Estimated total biomass by ICES rectangle in Figure M.58. IESNS. Estimated total biomass by ICES rectangle in

71 Figure M.59. IESNS. Estimated total biomass by ICES rectangle in Figure M.60. IESNS. Estimated total biomass by ICES rectangle in

72 Icelandic Acoustic Survey, July August (ICEAC) (survey tracks in red, only visible if no fish were recorded) Figure M.61. ICEAC. Estimated total biomass by ICES rectangle in Figure M.62. ICEAC. Estimated total biomass by ICES rectangle in

73 Figure M.63. ICEAC. Estimated total biomass by ICES rectangle in Figure M.64. ICEAC. Estimated total biomass by ICES rectangle in

74 Figure M.65. ICEAC. Estimated total biomass by ICES rectangle in Figure M.66. ICEAC. Estimated total biomass by ICES rectangle in

75 Figure M.67. ICEAC. Estimated total biomass by ICES rectangle in

76 Norwegian bottom trawl survey in the Barents Sea in January March (BARWINS) (trawl stations in red, only visible if no fish were recorded) Figure M.68. BARWINS. Swept estimate, total biomass by ICES rectangle in Figure M.69. BARWINS. Swept estimate, total biomass by ICES rectangle in

77 Figure M.70. BARWINS. Swept estimate, total biomass by ICES rectangle in Figure M.71. BARWINS. Swept estimate, total biomass by ICES rectangle in

78 Figure M.72. BARWINS. Swept estimate, total biomass by ICES rectangle in Figure M.73. BARWINS. Swept estimate, total biomass by ICES rectangle in

79 Figure M.74. BARWINS. Swept estimate, total biomass by ICES rectangle in Figure M.75. BARWINS. Swept estimate, total biomass by ICES rectangle in

80 Figure M.76. BARWINS. Swept estimate, total biomass by ICES rectangle in Figure M.77. BARWINS. Swept estimate, total biomass by ICES rectangle in

81 Figure M.78. BARWINS. Swept estimate, total biomass by ICES rectangle in Figure M.79. BARWINS. Swept estimate, total biomass by ICES rectangle in

82 Figure M.80. BARWINS. Swept estimate, total biomass by ICES rectangle in Figure M.81. BARWINS. Swept estimate, total biomass by ICES rectangle in

83 Figure M.82. BARWINS. Swept estimate, total biomass by ICES rectangle in Figure M.83. BARWINS. Swept estimate, total biomass by ICES rectangle in

84 Joint Norwegian/Russian ecosystem survey in the Barents Sea August September (BARAUTA) (survey tracks in red, only visible if no fish were recorded) Figure M.84. BARAUTA. Estimated total biomass by ICES rectangle in Figure M.85. BARAUTA. Estimated total biomass by ICES rectangle in

85 Figure M.86. BARAUTA. Estimated total biomass by ICES rectangle in Figure M.87. BARAUTA. Estimated total biomass by ICES rectangle in

86 Figure M.88. BARAUTA. Estimated total biomass by ICES rectangle in Figure M.89. BARAUTA. Estimated total biomass by ICES rectangle in

87 Figure M.90. BARAUTA. Estimated total biomass by ICES rectangle in Figure M.91. BARAUTA. Estimated total biomass by ICES rectangle in

88 Figure M.92. BARAUTA. Estimated total biomass by ICES rectangle in Figure M.93. BARAUTA. Estimated total biomass by ICES rectangle in

89 Russian trawl-acoustic survey in the Barents Sea, October- December (BARRUS) (survey tracks not available) Figure M.94. BARRUS. Estimated total biomass by ICES rectangle in Figure M.95. BARRUS. Estimated total biomass by ICES rectangle in

90 Figure M.96. BARRUS. Estimated total biomass by ICES rectangle in Figure M.97. BARRUS. Estimated total biomass by ICES rectangle in

91 Figure M.98. BARRUS. Estimated total biomass by ICES rectangle in Figure M.99. BARRUS. Estimated total biomass by ICES rectangle in

92 Figure M.100. BARRUS. Estimated total biomass by ICES rectangle in Figure M.101. BARRUS. Estimated total biomass by ICES rectangle in

93 Figure M.102. BARRUS. Estimated total biomass by ICES rectangle in Figure M.103. BARRUS. Estimated total biomass by ICES rectangle in

94 Figure M.104. BARRUS. Estimated total biomass by ICES rectangle in Figure M.105. BARRUS. Estimated total biomass by ICES rectangle in

95 Figure M.106. BARRUS. Estimated total biomass by ICES rectangle in Figure M.107. BARRUS. Estimated total biomass by ICES rectangle in

96 Faroese bottom trawl survey, March (FO-GFS-Q1) Figure M.108. FO-GFS-Q1. Average catch-pr-unit-effort (kg/hour) by ICES rectangle. Faroese bottom trawl survey, August (FO-GFS-Q3) Figure M.109. FO-GFS-Q3. Average catch-pr-unit-effort (kg/hour) by ICES rectangle. 96

97 Norwegian shrimp survey in Skagerrak Norwegian Deep (SHRIMPS) (trawl stations in red, only visible if no fish were recorded) Figure M.110. SHRIMPS. Swept estimate, total biomass by ICES rectangle in Figure M.111. SHRIMPS. Swept estimate, total biomass by ICES rectangle in

98 Figure M.112. SHRIMPS. Swept estimate, total biomass by ICES rectangle in Figure M.113. SHRIMPS. Swept estimate, total biomass by ICES rectangle in

99 Figure M.114. SHRIMPS. Swept estimate, total biomass by ICES rectangle in Figure M.115. SHRIMPS. Swept estimate, total biomass by ICES rectangle in

100 Figure M.116. SHRIMPS. Swept estimate, total biomass by ICES rectangle in Figure M.117. SHRIMPS. Swept estimate, total biomass by ICES rectangle in

101 Figure M.118. SHRIMPS. Swept estimate, total biomass by ICES rectangle in Figure M.119. SHRIMPS. Swept estimate, total biomass by ICES rectangle in

102 Figure M.120. SHRIMPS. Swept estimate, total biomass by ICES rectangle in Figure M.121. SHRIMPS. Swept estimate, total biomass by ICES rectangle in

103 Figure M.122. SHRIMPS. Swept estimate, total biomass by ICES rectangle in Figure M.123. SHRIMPS. Swept estimate, total biomass by ICES rectangle in

104 Figure M.124. SHRIMPS. Swept estimate, total biomass by ICES rectangle in Figure M.125. SHRIMPS. Swept estimate, total biomass by ICES rectangle in

105 Scottish IBTS surveys Figure M.126. North Sea Quarter 1. Mean number pr trawl hour Figure M.127. North Sea Quarter 3. Mean number pr trawl hour

106 Figure M.128. Scotland West Coast Quarter 1. Mean number pr trawl hour Figure M.129. Scotland West Coast Quarter 4. Mean number pr trawl hour

107 Figure M.130. Rockall Quarter 3. Mean number pr trawl hour

108 English surveys Figure M.131. Celtic Sea and Western approaches groundfish survey (WCGFS). Average catch-pr-unit-effort (kg/hour) Figure M.132. IBTS in the North Sea Q3. Average catch-pr-unit-effort (kg/hour)