Not to be cited without prior reference to and permission from the author.
1st annual report on groundfish assemblage species composition
and diversity
Helen Fraser & Simon Greenstreet
FRS Marine Laboratory, PO Box 101, 375 Victoria Road, Aberdeen, AB11 9DB, Scotland, UK
H.Fraser@marlab.ac.uk
Work Package 5
Deliverable 6
MAFCONS Report 2004:001
Managing Fisheries to Conserve Groundfish and Benthic Invertebrate Species Diversity
(MAFCONS Project: EC project number Q5RS-2002-00856)
MAFCON S
CONTENTS
1.
INTRODUCTION .......................................................................................................................... 3
2.
METHODS...................................................................................................................................... 4
3.
RESULTS........................................................................................................................................ 8
DISTRIBUTION ....................................................................................................................................... 8
TOTAL NORTH SEA IBTS AND STOCK ASSESSMENT DERIVED BIOMASS ESTIMATES ............................ 9
FISH ASSEMBLAGES ............................................................................................................................ 10
DIVERSITY MEASURES ........................................................................................................................ 11
NORWEGIAN DATA .............................................................................................................................. 12
DUTCH 8M-BEAM TRAWL DATA........................................................................................................... 13
4.
DISCUSSION................................................................................................................................ 16
5.
REFERENCES ............................................................................................................................. 19
2
1. Introduction
Species diversity is affected by fishing, but the relationship is unclear (Greenstreet &
Hall 1996, Greenstreet et al 1999, Rogers et al 1999). The Rio Convention on
Biological Diversity (CBD) requires that ecosystems be exploited in such a way that
biological diversity is conserved. Indeed, article 8 of the CBD goes further than this in
requiring that degraded systems should actually be restored. Similar sentiments are
included in article 2 of Annex V (Protection and Conservation of the Ecosystems and
Biological Diversity of the Maritime Area) of the OSPAR (Protection of the Marine
Environment of the North-East Atlantic) Convention. The Statement of Conclusions
from the 1997 Intermediate Ministerial Meeting on the Integration of Fisheries and
Environmental Issues in Bergen, and the subsequent Ministerial Declaration following
the Bergen 2002 North Sea Ministerial Conference, makes it clear that fisheries
managers will be required to balance fisheries and environmental objectives. These
include the effects of fishing on the species diversity of fish and benthic invertebrate
communities. To do this, the relationship between fishing and species diversity needs
to be clearly defined to allow managers to predict the consequences of fisheries
management policy on species diversity in much the same way as they currently
predict the effects of particular levels of fishing mortality on future stock size.
In this first report we focus on the groundfish assemblage species composition and
diversity. MAFCONS sampling took place on the Quarter 3 ICES International
Bottom Trawl Survey (IBTS) so the full Q3 IBTS database is used to estimate the
abundance and distribution of demersal fish species. Nine demersal fish species are
considered; haddock Melanogrammus aeglefinus, whiting Merlangius merlangus, cod
Gadus morhua, Norway pout Trisopterus esmarki, grey gurnard Eutrigla gurnardus,
plaice Pleuronectes platessa, lemon sole Microstomus kitt, common dab Limanda
limanda and long rough dab Hippoglossoides platessoides.
These nine species
account for over 90% of the biomass of demersal fish assemblage in the North Sea.
3
2. Methods
The EC funded project, MAFCONS (Managing Fisheries to Conserve Groundfish and
Benthic Invertebrate Species Density) began in January 2003. The IBTS 3rd Quarter
data will be used to assess changes in groundfish density during the duration of the
project. The methods described will be used to analyse the groundfish data provided
by the German, English, Norwegian, and Scottish partners. The Dutch do not take
part in the IBTS 3rd Quarter bottom trawl survey and instead participate in the Beam
Trawl Survey (BTS) using an 8m-beam trawl. The 8m-beam trawl dataset for 2003
can be analysed using the methods described and will be compared with the results
obtained using the GOV.
Norwegian data
The Norwegian fishing data was not included in the 2003 analysis of the fishing data
as all of the 14 tows were less than 25 minutes long. The 2003 Norwegian data has
been analysed as described in the methods above but is presented separately in the
results section.
Dutch data
The Dutch 8m-beam trawl data for 2003 has been analysed as described in the
methods above but is presented separately in the results section.
ICES International Bottom Trawl Survey (IBTS) data for quarter 3 (Q3) for the period
1998 to 2003 were collated into two databases, Haul Summary Information and
Species Abundance at length data. Only hauls of exactly 30 minutes duration were
analysed to keep the effects of effort variation to a minimum.
To calculate fish density, estimates of the area sampled were required. Gear geometry
data i.e. door-spread, wing-spread, headline height (Figure 2.1), were obtained using
SCANMAR© recording units. Two measures of the area swept by the trawl gear were
determined. Firstly the area swept by the whole gear i.e. between the otter boards, is
given by:
Gear Swept Area (GSA) m2 = Mean Door Spread (m) x Distance Towed (m)
4
Secondly the area swept by the net, i.e. between the wing ends of the trawl, is given
by:
Net Swept Area (NSA) m2 = Mean Wing Spread (m) x Distance Towed (m)
Data on door and wing-spread were not available for a substantial number of the hauls
included in the analysis. Scottish SCANMAR© data for the years 1998, 2001, 2002
and 2003 were therefore analysed to determine the relationships between the two
parameters and depth. The relationships in all four years were similar so the
regression analysis was performed on the combined data (Figure 2.2). For samples
where net geometry information was missing, mean door- and wing-spread could then
be estimated from the depth information using the following equations:
Mean Door Spread = 33.251 x log Depth + 15.744
Mean Wing Spread = 6.8515 x log Depth + 5.8931
Where no depth data were available for a trawl sample, the average depth recorded on
other occasions that the station was fished was applied. The distance towed for each
haul is not a mandatory value in the ICES database. Where this information was
missing the average distance towed for all trawls in that particular year was used.
Data in the ICES database are stored as the number of fish caught in each length class
raised to one hour’s fishing effort. In order to estimate densities in the original 30min
tows all numbers at length were divided by 2. Fish density was calculated using the
following formula:
Fish Density (nos. m-2) = Total Number of Fish per ½ hour tow / Swept Area Measure (m2)
In most years some statistical rectangles were fished more than once. In these cases
the total number of fish caught in all samples in the rectangle was divided by the total
area swept by all trawls in the rectangle combined to give the fish density estimate for
that particular statistical rectangle.
5
To estimate biomass density, weight-at-length data are necessary. Since such data are
not available in the ICES database, weight-at-length relationships maintained by FRS
Marine Laboratory, Scotland, were used (e.g. Coull et al 1989). These relationships
were used to convert numbers at length in the database to weight at length. Biomass
density was then determined as:
Fish Biomass Density (Kg.m-2) = Total Weight of Fish per ½ hour tow / Swept Area Measure (m2)
In order to determine the IBTS derived biomass estimate of fish present in each entire
statistical rectangle, these density estimates need to be multiplied by the “sea area” of
the rectangle. As you move further north, the width of each statistical rectangle
decreases due to the curvature of the earth. Taking this into account, the area of each
rectangle was determined and then multiplied by the proportion that was sea to give
the “sea area” in each ICES rectangle. The IBTS derived biomass estimate of each
species present in each ICES statistical rectangle could then be estimated by
multiplying species density by the sea area of each rectangle. Total species IBTS
derived biomass estimates for each year were determined by summing the rectangle
biomass estimates over all rectangles.
In each of the six years there were at least two statistical rectangles where no fishing
took place. For these missing rectangles an IBTS derived biomass estimate value was
interpolated based on the mean of the IBTS derived biomass estimates in the
surrounding statistical rectangles.
Figure 2.3 shows the full extent of ICES area IV. The rectangles shaded light blue
were included in the IBTS in at least one of the six years and were therefore included
in the analysis. Areas shown in white were not included in the analysis so the total
biomass stock estimates determined from the IBTS for the whole North Sea are for an
area slightly smaller than the full ICES area IV. In order to compare these IBTS
derived biomass estimates with biomass estimates derived for the full ICES area IV
by the ICES Working Group on the Assessment of Demersal Stocks in the North Sea
and Skagerrak (WGNSSK) (ICES 2003), the IBTS derived biomass estimates were
adjusted by a raising factor determined by the ratio:
6
Raising Factor = ICES Area IV area (m2) / Area covered by the IBTS survey (m2)
To take account of the fact that fish were not evenly distributed across the North Sea,
raising factors were determined for the five separate sub-areas indicated in Figure 2.3
(Table 2.1).
Figure 2.4 shows the total number of hauls in each statistical rectangle within the
study area in each year and Figure 2.5 shows the total number of times each statistical
rectangle was fished over the six-year period 1998 to 2003. Figure 2.6 shows position
of the stations that were fished as part of the MAFCONS project in 2003.
7
3. Results
The analyses presented here use density estimates derived using the area swept by the
net. Densities of species that may have been herded into the path of the net to a
significant extent by the action of the otter boards and sweeps may be over-estimated
relative to species not susceptible to such herding effects. Data are presented for nine
species: haddock, whiting, cod, Norway pout, grey gurnard, plaice, lemon sole,
common dab, and long rough dab. These nine species account for between 91% and
98% of the individual fish sampled from the demersal component of the fish
assemblage in each year by the IBTS (Table 3.1).
Distribution
Figures 3.1 to 3.9 illustrate variation in the biomass of each of the nine species in each
year in each ICES rectangle covered by the IBTS. Haddock were mainly confined to
the north-western North Sea in all six years (Figure 3.1). Whiting were more
ubiquitous, but the largest biomasses tended to occur off the east coast of Britain and
in the southern North Sea (Figure 3.2). Cod were also found over most of the North
Sea, albeit in low numbers, but the largest biomass occurred in the north-eastern
North Sea (Figure 3.3). Norway pout were mainly limited to the northern half of the
North Sea in most years, although there was some indication of a southerly expansion
of the distribution in 2000 (Figure 3.4). Figure 3.5 shows the distribution of Grey
gurnard biomass over the whole North Sea. Grey gurnards were found over much the
IBTS area, but were most abundant across the centre of the North Sea. Rectangle
biomass estimates were low both north of 57.5°N and south of 53.5°N (Figure 3.5).
Plaice were found over much of the area, but were relatively scarce in the northeastern North Sea (Figure 3.6). The largest biomasses of lemon sole were located in
the northern North Sea, just to the south of the Shetland Isles. Lemon sole biomass in
the south-eastern North Sea was low (Figure 3.7). Common dab were mainly confined
to the southern half of the IBTS area, with biomass highest in the south-east and
central North Sea, particularly off the coasts of Denmark and Holland (Figure 3.8).
Long rough dab were most abundant in the central North Sea. Whilst their distribution
extended into the northern North Sea, almost no long rough dab were sampled south
of 53.5°N (Figure 3.9). The actual rectangle biomass data for each species are given in
figures 4.10 to 4.18.
8
Total North Sea IBTS and Stock Assessment Derived Biomass Estimates
Summing the individual rectangle IBTS derived biomass estimates across all ICES
rectangles in the IBTS survey area (including interpolated values) provided IBTS
derived estimates of the total biomass of each species in the area covered by the IBTS
for each year. Table 3.2 gives the results of this summing procedure for each of the
five sub-areas of the North Sea (see Figure 2.3) and also provides the raising factors
for each sub-area to raise these totals to the whole of ICES area IV. Table 3.2 then
gives the results following the application of these raising factors for each sub-area,
and gives the area totals (IBTS area and ICES area IV) after summing across the five
sub-areas. Annual variation in total IBTS derived biomass estimate for the whole of
ICES area IV for each of the nine species is illustrated in Figure 3.19. The raised
IBTS derived biomass estimate for haddock increased to a peak of 1,065,416t in 2000,
then subsequently declined. Whiting biomass increased to a peak of 745,376t in 2001
and then decreased in the following two years. The biomass of cod decreased from
82,615t in 1998 to 42,660t in 2000, biomass rose slightly again in 2001 then
decreased sharply to 23,187t in 2003. Norway pout biomass rose to a peak of 532,258t
in 2000 and has decreased sharply since. Grey gurnard biomass has remained
relatively constant over the six-year period, fluctuating around a biomass of
approximately 80,000t. Plaice biomass increased to a peak of 30,571t in 1999, then
decreased to a low of under 16,000t in 2000, and has then increased in each
subsequent year. Lemon sole biomass has remained relatively constant at around
25,000t. Common dab biomass was relatively stable at 150,000t from 1998 to 2000,
then increased rapidly to just under 240,000t in 2001, and its biomass has remained
relatively stable since then. Long rough dab biomass has remained relatively constant
over the six-year period at about 25,000t.
With some exceptions, the trends in the total North Sea biomass of each of the nine
species indicated by the IBTS follow closely the ICES stock assessment estimates.
The difference in the ICES area IV biomass estimates for cod, haddock, whiting,
Norway pout and plaice in each year derived from the IBTS and the equivalent annual
stock assessments made by the WGNSSK (Working Group on the North Sea and
Skagerrak) are shown in Figure 3.20. The peak haddock biomass indicated by the
stock assessment is picked up in the IBTS signal, but the amplitudes differ. This
difference may be caused by over estimation of the large 1999 recruit cohort strength
9
by the assessment process, and the difference may decline with future iterations of the
VPA analysis in subsequent annual stock assessment exercises.
Otherwise the
haddock biomass estimates derived from the VPA are in close agreement with the
IBTS derived estimates. The two whiting abundance trends follow similar trajectories,
but the IBTS estimates are a factor of two to three times higher, suggesting a
catchability in the GOV trawl of >1. For all other species, the IBTS derived biomass
estimates are lower than the equivalent stock assessment estimates suggesting
catchabilities of less than one in the IBTS. In the case of plaice, the assessment
biomass estimates exceed the IBTS derived estimates by at least one order of
magnitude. This is a clear indication of how badly the GOV trawl samples flatfish.
Norway pout stock assessment estimates are approximately 6 times higher than the
equivalent IBTS biomass estimates.
Fish Assemblages
In each year, the total number of individual fish of each species present in each
statistical rectangle was estimated. Cluster analysis was performed on these data to
group together rectangles with similar species composition, and distinguish between
groups of rectangles with different species relative abundance composition. An
example of the dendrogram produced by this analysis is provided in Figure 3.21, in
this case for the year 1998. Similar dendrograms where obtained in all other years.
For each year the main clusters, potentially different “fish communities”, were
defined at a Bray-Curtis similarity of about 35%. This level of similarity left a single
large single “fish community” cluster located geographically across most of the
central and northern North Sea (Figure 3.22). This cluster broke down into two
consistent sub-clusters at a similarity of around 40% (Figures 3.21 and 3.22). The
spatial clustering of the species abundance data was reasonably consistent from year
to year, suggesting the presence of distinct fish communities. These communities
tended to exist as bands straddling the North Sea more or less with a south-west to
north-east orientation. The locations of the boundaries between communities were
reasonably stable in time. The data from all years were combined to produce a
composite indication of the spatial extent of each “fish community” cluster across all
six years (Figure 3.23).
The same analysis was repeated but with the species
considered to be pelagic, and thus not consistently sampled by the GOV trawl,
excluded from the analysis. The pattern of clustering based on just the demersal
10
species (Figure 3.24) was similar to that observed when all fish were included (Figure
3.22). Combining the data for all years for the demersal species only (Figure 3.25)
again produced very similar clustering to the clustering observed when all fish were
included (Figure 3.23).
In each year the average weight of all individual fish in the demersal fish community
occupying each rectangle was estimated (Figure 3.26), this being one of the metrics
considered to indicate best the impact of fishing on fish communities (ICES 2001),
and accepted as an element of Ecological Quality for Fish Communities at the Bergen
Ministerial North Sea Conference in 2002. Demersal fish communities consisting of
the largest fish were found around the 200m depth contour towards the north of the
IBTS region and the along the western edge of the Norwegian deeps.
Mean
individual weight in the demersal fish community also appeared to be higher in a
region extending out in to the central North Sea from the east-coast of the UK. For
each of the four fish community clusters identified in Figure 3.25, trends in the mean
weight of demersal fish over the six-year period for which data were analysed are
shown in Figure 3.27. Both positive and negative slopes were detected but none were
statistically significant. This is not surprising given the small sample size. These data
could provide baseline information from which to monitor the effects of remedial
action taken to mitigate long term declines in this community indicator.
Diversity Measures
Figures 4.28 to 4.31 show spatial variation in four different measures of diversity,
Species richness (S), Shannon-Wiener (H’), Simpson index (λ) and Hills N2. These
diversity indices were calculated on the combined species abundance for all hauls
made in each statistical rectangle over the six years 1998 to 2003 for statistical
rectangles that were fished more than five times within the time period. Species
richness ranged from 14 to 41 species (Figure 3.28) and was highest in the north and
in the south, with the lowest number of species being found in the central North Sea.
The highest number of species (41) was found in 32F1 and the lowest number of
species (14) was found in 42F2. The Shannon-Wiener index (Figure 3.29) ranged
from 0.30 to 1.93. The largest value of 1.93 was found in 41E8 and the smallest value
was in 33F3. Simpson’s index (Figure 3.30) is an index of dominance, in the sense
that the largest values correspond to assemblages whose total abundance is dominated
11
by one, or a very few, of the species present. The largest value of 0.88 was in 33F3
where the fish assemblage was dominated by Horse mackerel (Trachurus trachurus).
Hill’s (1973) N2 index is the reciprocal of Simpson’s index. This transformation
converts the index into a more traditional diversity index, with increasing numerical
value indicating greater community species diversity. This index effectively indicates
the number of species that in effect dominate the community. The more species that
effectively dominate the community, the more diverse the community is. Values of
Hill’s N2 ranged from 1.12 – 5.69 with the largest value, the most diverse community,
in 43F5 and the smallest value, the least diverse community, in 33F3 (corresponding
to the largest value of the Simpson index). Generally, diversity tended to be higher in
the western North Sea, and in a band stretching across the central North Sea to the
Danish coast.
Norwegian data
The Norwegian data for 2003 is presented separately as all of the tows were less than
25 minutes long and were therefore not included in the analysis of the whole IBTS
dataset. The purpose of analysing the Norwegian data alone was to compare the
biomass estimates made using tows of less than 25 minutes with those calculated
using tows of exactly 30 minutes duration. Figure 3.32 shows the location of the
stations fished by the Norwegian partners in 2003. An estimate of the biomass of the
nine major demersal species for each of the statistical rectangles sampled by the
Norwegians was made using only the Norwegian data. These estimates were then
compared with those made using the 2003 IBTS dataset for the same statistical
rectangles and the results can be seen in Figure 3.33.
Figure 3.33 shows that
consistently the biomass estimates made using the whole IBTS dataset for 2003 were
higher than those using just the Norwegian data, except possibly for the plaice and
lemon sole. Figure 3.34 shows the cumulative species curves for both the Norwegian
data and the IBTS data for the same statistical rectangles. The figure shows that the
IBTS data contains more species than the Norwegian data in the same statistical
rectangles. This is not entirely unexpected as the IBTS data contains the trawl data
from all participating countries in 2003 (except the Norwegian data), so each
statistical rectangle may have been fished multiple times. This was not the case for
the Norwegian data, each statistical rectangle was only fished once (but only for 20
12
minutes whereas all the IBTS stations included in the analysis were fished for 30
minutes).
Dutch 8m-beam trawl data
Figure 3.35 shows the location of the Dutch 8m-beam trawling during the 3rd Quarter
Beam trawl survey (BTS) in 2003. The analysis of the IBTS dataset has focused on
nine main demersal species (haddock, whiting, cod, Norway pout, grey gurnard,
plaice, lemon sole, common dab and long rough dab) which in all years since 1998
have made up over 92% of the demersal fish assemblage.
The percentage
contribution of these same nine species to the total demersal fish assemblage
estimated using the 2003 Dutch 8m-beam trawl survey is only 72% in comparison.
Figure 3.36 shows that when four more species (Starry ray, Raja radiata, Lesser
weever, Echiichthys vipera, Scaldfish, Arnoglossus laterna and Dover sole, Solea
solea) are added to the 8m-beam trawl data, the percentage contribution of these 13
fish increases by 18% to 90%. If these same four extra species are added to the GOV
data, then the percentage contribution increases by only 1.97% to 94.5%.
Biomass estimates of the main demersal species were derived for each statistical
rectangle fished by the Dutch in 2003 using the methods described above. These
biomass estimates were then compared with those calculated using the IBTS, 2003
dataset. In order to be able to see the difference in biomass calculated using the two
different survey methods, the biomass estimates made using the 8m-beam trawl were
subtracted from those made using the IBTS, 2003 dataset. The differences in biomass
for each species can be seen in Figures 3.37 to 3.45. In these figures, if the symbol is
red then the 8m-beam trawl estimates were higher than those made using the GOV, if
the symbol is black then the biomass estimate made using the GOV was greater than
the biomass calculated using the 8m-beam trawl. The results show that as expected,
biomass estimates made using the GOV were consistently higher than those made
using the 8m-beam trawl for haddock (Figure 3.37), whiting (Figure 3.38), Norway
pout (Figure 3.40) and grey gurnard (Figure 3.41). The biomass estimates made using
the 8m-beam trawl were consistently higher for plaice (Figure 3.42) and lemon sole
(Figure 3.43). There was no consistent pattern for the biomass estimates of cod
(Figure 3.39), common dab (Figure 3.44) and long rough dab (Figure 3.45).
13
The total number of each fish species caught using each survey method in every
statistical rectangle where both gears had been used was calculated and the results for
a selection of species are shown in Figure 3.46. The fish have been divided in to two
types, ‘roundfish’ and ‘flatfish’.
Figure 3.46 shows that the GOV caught more
roundfish than the beam trawl and the 8m-beam trawl caught more flatfish than the
GOV.
The cumulative species curves for the 8m-beam trawl and GOV over the same
statistical rectangles are shown in Figure 3.47. The Figure shows that the GOV
caught more species in each statistical rectangle than the 8m-beam trawl. It must be
remembered that in the GOV dataset there were multiple hauls in each statistical
rectangle, whereas in the 8m-beam trawl dataset there was only one haul per statistical
rectangle. Also the swept area of the GOV is much higher than that of the beam
trawl.
Figures 4.48 to 4.51 show spatial variation in four different measures of diversity,
Species richness (S), Shannon-Wiener (H’), Simpson index (λ) and Hills N2. These
diversity indices were calculated on the combined species abundance for all hauls
carried out in each statistical rectangle sampled during the Dutch beam trawl survey in
2003 and the results for both the GOV and 8m-beam trawl are shown for each year.
Species richness calculated using the 8m-beam trawl data (Figure 3.48) was highest in
the south and around the Scottish coast. Species richness ranged from 6 to 24 species
with the highest number of species being found in statistical rectangles 42E8 and
34F2 and the lowest in 42F4. Species richness calculated using the IBTS data was
highest in the north and lowest in the east. Species richness ranged from 2 to 28 with
the highest number of species in 49E9 and the lowest in 35F0. The Shannon-Weiner
index (Figure 3.49) ranged from 0.58-2.56 when calculated using the 8m-beam trawl
data. The highest value was 2.56 in 50E9 and the lowest value of 0.58 in 41F4. The
Shannon-Weiner index ranged from 0.27-1.89 when using the GOV data with the
highest value in 42E8 and the lowest in 42F0. The Simpson index (Figure 3.50) is an
index of dominance, in the sense that the largest values correspond to assemblages
whose total abundance is dominated by one, or very few of the species present. Using
the 8m-beam trawl data set, the largest value of 0.73 was in statistical rectangle 41F4
where the fish assemblage was dominated by the starry ray (Raja radiata), the
14
smallest value of 0.11 was in statistical rectangle 50E9. Using the GOV data the
largest value of 0.90 was in statistical rectangle 42F0 where the fish assemblage was
dominated by herring (Clupea harengus) and the smallest in 39F0. Using the 8mbeam trawl dataset, Hill’s N2 (Figure 3.51) ranged from 1.36 to 8.43 with the largest
value, the most diverse community in 50E9 and the smallest value, the least diverse
community, in 41F4 (corresponding to the largest value of the Simpson index). Using
the GOV data Hill’s N2 ranged from 1.11 to 4.85 with the most diverse community in
39F0 and the least diverse community in 42F0.
15
4. Discussion
The purpose of this report was to present the data collected by the MAFCONS
partners in 2003 and to investigate the types of analyses which can be considered
when assessing ground fish species composition and diversity and the types of
problems which arise when using this kind of data. The main bulk of the data
presented here is that of the IBTS 3rd Quarter surveys from 1998 to 2003. The
distribution maps of the nine demersal species show very distinct patterns. Analysis
here has shown that by using alternative data sources, such as the Dutch 8m-beam
trawl survey data, collected in the same area at the same time, quite different results
can be obtained.
The comparison between the abundance and biomass of species such as haddock and
plaice in the GOV and 8m-beam trawl shows very clearly the difference in
catchability of these two species in different gears. Recent work comparing the
catchability of plaice, compared with other roundfish species in GOV trawls and beam
trawls would appear to confirm the relatively low catchability of plaice in the GOV
(ICES 2004a, 2004b). Obviously the issues regarding the catchability of different
species in different gears need to be taken in to consideration when looking at
measures of species diversity. The comparison between diversity measures such as
species richness and Simpson’s index calculated using the Dutch 8m-beam trawl data
and the 2003 GOV show that the results can very different for the two different gears.
The stock biomass estimates produced by ICES stock assessment working groups are
based on virtual population analysis of commercial landings data. The biomass
estimates derived here using the IBTS 3rd Quarter survey are, with the exception of
whiting, lower than those produced by the ICES WGNSSK. Fundamentally, this
deviation can mainly be explained by the fact that trawl gear catchability is generally
less than 1.0; trawls do not catch all the fish in the path of the net. Because of this,
there will always be more fish in the sea than the catch densities of trawl surveys
would suggest, but how much more? The differences each year between the IBTS
derived total North Sea biomass estimates and the stock assessment biomass estimates
for plaice were larger than for the four roundfish species, suggesting that this species
had the lowest catchability in the GOV. Apparent catchabilities of the four roundfish
species varied from approximately 0.25 for cod and Norway pout, 1.0 for haddock, to
16
1.76 for whiting. The apparent catchability in excess of 1.0 for whiting may be due to
the herding effect of the otter boards on whiting in the path of the gear. In effect a
much larger area is being sampled for whiting than is allowed for by the Net Swept
Area. The distance between the otter boards is approximately 3.5 times greater than
the distance between the trawl wing ends. If Gear Swept Area were to be used instead
to estimate whiting densities, then the IBTS biomass estimates become approximately
half the value of the assessment stock biomass estimates. The larger mesh size used in
GOV research trawls compared with trawls used in the commercial industrial fishery
for Norway pout could help to explain the apparent low catchability of this species in
the GOV.
It is evident from the data presented here that is would be very useful to have the full
3rd Quarter 8m-beam trawl survey (BTS) dataset made available to the MAFCONS
project. It is the intention to acquire the whole of the BTS dataset for the same time
period as the IBTS data (1998 to 2003). The biomass estimates for plaice and Dover
sole derived using the BTS data could then be compared with those produced by the
WGNSSK. Also, if the whole BTS dataset were available then differences in the
catchability of the two gears could be more accurately obtained.
In the past survey catches of assessed species have been compared with stock
assessment data in effect to estimate apparent catchabilities in a similar way. The
whole suite of species caught in the survey has been divided into groups of species
considered to have similar catchabilities. The number of different groups was limited
by the fact that each group had to include at least one assessed species for which there
was a biomass estimate determined by VPA. Thus species such as grey gurnards and
lesser spotted dogfish (Scyliorhinus caniculus) were grouped with cod, haddock and
whiting, species such as poor cod (Trisopterus minutus) were grouped with Norway
pout, and flatfish, skates and rays were grouped with plaice and sole. By comparing
the catch rates of non-assessed and assessed species in each group, and relating these
to the VPA estimate of the biomass of the assessed species, estimates of the biomass
of the non-assessed species were determined. In this way estimates of the total
biomass of the entire fish community were made (Yang 1982; Sparholt 1990; Daan et
al 1990). A similar approach can be adopted here, and the distribution maps used to
17
distribute the biomass of each species across the entire North Sea. Thus the total
biomass of each species in each rectangle can be estimated.
The Norwegian fish data collected in 2003 has been analysed separately in this report.
This data was kept separate as it was agreed in the MAFCONS methods manual that a
valid fishing tow should be 30 minutes long as this is the standard duration of an
ICES GOV tow. In 2003 all of the Norwegian tows were either 20 minutes or less in
duration. In this report initial analysis investigating what effect tow duration has on
the number of species caught in the GOV has begun. Once this analysis has been
finished then a decision can be made as to whether to include the Norwegian data in
to the full analysis of the 2003, IBTS data.
18
5. References
Coull, K.A, Jermyn, A.S, Newton, A.W & Hall, W.B (1989) Length/Weight
Relationships for 88 species of fish encountered in the North East Atlantic. Scottish
Fisheries Research Report, 43, 100pp.
Daan, N, Bromley, P. J, Hislop, J.R.G & Nielsen, N.A (1990) Ecology of North
Sea Fish. Netherlands Journal of Sea Research, 26 (2-4), 343-386.
Greenstreet, S.P.R & Hall, S.J. (1996) Fishing and the ground-fish assemblage
structure in the north-western North Sea: an analysis of long-term and spatial trends.
Journal of Animal Ecology, 65, 577-598.
Greenstreet, S.P.R, Spence, F.E & McMillan, J.A (1999) Fishing effects in
northeast Atlantic shelf seas: patterns in fishing effort, diversity and community
structure. V. Changes in structure of the North Sea groundfish assemblage between
1925 and 1996. Fisheries Research, 40, 153-183.
Huston, A.H (1994) Biological Diversity: The Coexistence of Species on Changing
Landscapes. Cambridge University Press, 681pp.
ICES (2001) Report of the Working Group on Ecosystem Effects of Fishing
Activities. ICES C.M.,
ICES (2004a) Report of the Working Group on the Assessment of Demersal Stocks
in the North Sea and Skagerrak. ICES C.M.,ACFM:07
ICES (2004b) Report of the Working Group on Fish Ecology. ICES C.M.,G:09
Rogers, S.I., Maxwell, D, Rijnsdorp, A.D, Damm, U & Vanhee, W (1999) Fishing
effects in northeast Atlantic shelf seas: patterns in fishing effort, diversity and
community structure. V. Can comparisons of species diversity be used to assess
human impacts on coastal demersal fish faunas in the Northeast Atlantic? Fisheries
Research, 40, 135-152.
19
Sparholt, H (1990) An estimate of the total biomass of fish in the North Sea. J. Cons.
int. Explor. Mer. 46, 200-210.
Yang, J (1982) An estimate of the fish biomass in the North Sea. J. Cons. int. Explor.
Mer, 40, 172-191.
20
Table 2.1. Total area of each of the five sub-areas that make up the whole North Sea (whole ICES area
IV) and the area included within the IBTS coverage over the period 1998 to 2003. Raising factors to
“raise” the area covered by the IBTS to the entire ICES area IV are given for each sub-area.
Area
ICES area Km2
IBTS area Km2
Raising Factor
IVa1
133,049
100,900
1.3174468
IVa2
131,294
85,069
1.543383
IVb1
125,519
121,142
1.0361325
IVb2
151,764
143,427
1.0581291
IVc
66,572
46,655
1.4269104
21
Table 3.1. Numbers of all demersal fish and numbers of the nine selected species sampled by the IBTS
in each year. The contribution made by the nine species in each year is indicated.
Year
All demersal fish
Nine species
1998
1999
2000
2001
2002
2003
15,376,053
47,984,891
28,254,466
18,062,565
16,208,788
12,140,167
14,952,958
47,094,074
27,484,404
17,519,262
14,747,917
11,234,959
Percentage
contribution
97.2
98.1
97.3
97.0
91.0
92.5
22
Table 3.2. Raised area weighted catch (tonnes) for each of the nine demersal fish species in each of the
five sub-areas over the period 1998 to 2003. (HAD is haddock, WHI is whiting, COD is Cod, NPO is
Norway pout, GGU is grey gurnard, PLA is plaice, LSO is lemon sole, CDA is common dab, LRD is
long rough dab).
SP
AREA 1998
IBTS survey
1999 2000 2001
2002
2003
RF
1998
1999
Raised North Sea
2000 2001 2002
2003
HAD
IVa1
IVa2
IVb1
IVb2
IVc
TOTAL
107,498
48,942
128,128
18,659
17
303,245
171,662
181,174
129,227
19,270
18
501,351
279,287
150,882
344,137
101,722
277
876,304
219,713
177,537
274,368
26,749
1,098
699,465
202,633
172,204
231,290
20,813
0
626,940
215,541
77,156
145,562
77,656
0
515,915
1.3174
1.5434
1.0361
1.0581
1.4269
141,623
75,536
132,758
19,744
24
369,685
226,155 367,946
279,621 232,868
133,896 356,571
20,390 107,635
26
395
660,089 1,065,416
289,460
274,008
284,282
28,304
1,566
877,620
266,958
265,777
239,647
22,023
0
794,405
283,964
119,081
150,822
82,170
0
636,037
WHI
IVa1
IVa2
IVb1
IVb2
IVc
TOTAL
78,500
13,190
146,378
52,874
38,872
329,815
160,544
30,711
218,397
168,185
18,177
596,014
120,935
23,688
292,977
137,724
61,795
637,118
70,190
27,469
236,953
221,954
91,203
647,769
86,931
20,632
231,912
106,985
19,647
466,107
80,988
16,892
195,413
75,376
8,754
377,423
1.3174
1.5434
1.0361
1.0581
1.4269
103,420
20,358
151,667
55,947
55,468
386,860
211,508
47,399
226,288
177,961
25,937
689,094
92,471
42,396
245,514
234,856
130,138
745,376
114,528
31,843
240,292
113,203
28,035
527,900
106,697
26,071
202,474
79,757
12,491
427,491
COD
IVa1
IVa2
IVb1
IVb2
IVc
TOTAL
8,596
4,335
4,549
3,934
6,111
4,726
16,114 12,520 11,701 15,041
8,109
6,450
14,446
6,052
5,046
2,544
3,698
4,753
20,908 11,133
7,287 24,165
7,240
1,391
6,537
3,073
3,973
4,645
9,374
427
66,601 37,113 32,556 50,329 34,531 17,747
1.3174
1.5434
1.0361
1.0581
1.4269
NPO
IVa1
IVa2
IVb1
IVb2
IVc
TOTAL
GGU
60,956
36,603
1,231
4,096
0
102,886
75,336
94,246
20,326
674
0
190,583
207,808
101,272
97,266
1,323
0
407,669
11,324
5,711
24,871 19,323
14,968
6,271
22,123 11,780
9,328
4,385
82,615 47,470
80,307
56,492
1,275
4,334
0
142,408
5,993
5,183
8,050
6,226
18,058 23,214 12,515
9,955
5,228
2,635
3,832
4,925
7,710 25,570
7,661
1,472
5,669
6,628 13,375
610
42,660 63,230 45,433 23,187
79,433 70,834 46,258
57,793 20,951 16,382
16,129
4,301
2,076
1,735
1
81
35
0
0
155,124 96,086 64,796
1.3174
1.5434
1.0361
1.0581
1.4269
IVa1
IVa2
IVb1
IVb2
IVc
TOTAL
2,959
3,875
2,357
2,440
2,685
4,002
972
2,295
2,240
4,057
3,531
4,136
30,259 35,787 29,518 19,896 32,111 28,503
48,465 52,836 39,765 56,254 33,727 36,024
1,402
1,041
459
2,397
496
23
84,057 95,834 74,339 85,043 72,551 72,688
1.3174
1.5434
1.0361
1.0581
1.4269
3,898
5,105
1,501
3,542
31,352 37,080
51,283 55,907
2,001
1,485
90,034 103,120
3,105
3,215
3,537
5,273
3,457
6,261
5,450
6,383
30,585 20,615 33,272 29,533
42,077 59,524 35,687 38,118
655
3,420
708
33
79,878 93,034 78,654 79,339
PLA
IVa1
IVa2
IVb1
IVb2
IVc
TOTAL
662
1,437
829
2,077
1,558
1,841
115
299
293
493
543
520
2,709
2,170
3,335
3,717
5,585
4,904
17,997 20,306
8,412 11,467 10,872 14,400
939
3,140
1,050
2,257
2,099
1,160
22,422 27,353 13,919 20,010 20,658 22,824
1.3174
1.5434
1.0361
1.0581
1.4269
872
1,893
177
462
2,807
2,248
19,043 21,487
1,341
4,481
24,240 30,571
1,092
2,736
2,053
2,425
453
760
838
802
3,455
3,851
5,786
5,082
8,901 12,134 11,504 15,237
1,498
3,220
2,996
1,655
15,399 22,702 23,178 25,201
LSO
IVa1
IVa2
IVb1
IVb2
IVc
TOTAL
7,017
7,145 10,527 10,032
6,495
8,610
1,092
1,817
1,991
1,915
2,083
1,713
7,426
8,226
7,099
5,095
7,329
7,496
3,800
2,132
1,850
1,374
1,925
2,539
230
116
55
195
155
0
19,566 19,437 21,522 18,611 17,988 20,358
1.3174
1.5434
1.0361
1.0581
1.4269
9,245
9,413
1,686
2,805
7,695
8,523
4,021
2,256
328
166
22,974 23,163
13,868 13,217
8,557 11,344
3,073
2,955
3,215
2,644
7,355
5,279
7,594
7,766
1,957
1,454
2,037
2,686
79
279
221
0
26,333 23,183 21,624 24,441
CDA
IVa1
IVa2
IVb1
IVb2
IVc
TOTAL
3,583
7,369
5,509
4,718
4,896
2,494
2,663
8,034
4,247
6,922
5,048
5,181
30,108 44,235 32,649 43,828 67,708 40,642
98,250 82,311 72,240 118,451 143,598 153,965
7,930
7,260
4,484 35,032 10,249
5,119
142,534 149,209 119,129 208,952 231,500 207,401
1.3174
1.5434
1.0361
1.0581
1.4269
LRD
IVa1
IVa2
IVb1
IVb2
IVc
TOTAL
1,505
3,950
3,017
2,073
2,169
3,525
2,789
5,133
4,412
4,430
2,495
3,684
4,344
9,513
8,697
4,499 10,190
7,127
13,248
6,811
5,330
9,332
6,893
7,816
14
31
0
10
0
0
21,899 25,437 21,455 20,344 21,747 22,152
1.3174
1.5434
1.0361
1.0581
1.4269
4,720
4,110
31,196
103,961
11,315
155,303
99,251
145,458
21,060
714
0
266,483
159,325
36,560
303,563
145,730
88,176
733,353
9,709
12,400
45,833
87,096
10,359
165,396
1,983
5,204
4,304
7,922
4,500
9,857
14,018
7,206
20
44
24,826 30,233
273,776
156,302
100,780
1,400
0
532,258
7,257
6,554
33,829
76,440
6,398
130,478
104,648 93,320 60,943
89,197 32,335 25,283
16,711
4,456
2,151
1,835
1
85
50
0
0
212,443 130,112 88,462
6,215
10,684
45,412
125,337
49,988
237,636
6,450
3,286
7,792
7,996
70,155 42,110
151,945 162,915
14,625
7,305
250,966 223,611
3,974
2,731
2,857
4,644
6,809
6,838
3,851
5,686
9,011
4,661 10,558
7,384
5,640
9,874
7,294
8,271
0
14
0
0
25,434 24,118 24,560 25,985
23
Figure 2.1. Schematic drawing of a fishing net illustrating the terms “wing-spread” and “door-spread”.
Arrows indicate the possible herding effect of the otterboards and sweeps.
Door spread
Wing spread
Area swept by net
Area swept by gear
24
Figure 2.2. Relationship between mean wing and door spread and log depth using SCANMAR© data
collected on the Scottish 3rd Quarter IBTS.
24
Mean wing spread (m)
22
20
18
16
y = 6.8515x + 5.8931
R2 = 0.6762
14
1.2
1.6
2
Log mean depth (m)
2.4
100
Mean door spread (m)
90
80
70
60
y = 33.251x + 15.744
R2 = 0.7609
50
1.2
1.6
2
Log mean depth (m)
2.4
25
Figure 2.3. Areas shaded light blue are parts of ICES area IV which are included in the IBTS study
area. White areas are part of ICES area IV which are not included in the IBTS study areas. The IBTS
area has been divided in to five parts, area IVa1, IVa2, IVb1, IVb2, and IVc.
62
E6 E7
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
IVa1
IVa2
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
IVb2
IVb1
40
39
55
38
37
54
36
VIIa
35
53
IVc
34
33
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
26
Figure 2.4. Number of hauls in each statistical rectangle in each of the years 1998 to 2003.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
1
0
1
1
2
1
1
2
2
2
2
2
61
0
1
2
1
2
1
60
59
Degrees Latitude
58
1
1
57
1
1
56
0
1
1
0
2
2
1
2
2
2
1
2
2
1
1
55
54
0
2
0
2
1
2
1
2
1
2
1
2
2
0
2
2
2
0
VIIa
53
1
1
1
2
1
2
1
2
1
2
2
1
1
2
2
2
2
0
52
1
0
1
1
2
1
2
1
2
2
2
2
2
0
0
2
1
2
1
1
1
62
0
1
0
2
1
2
2
2
2
2
2
2
2
2
2
1
2
1
1
59
2
2
2
1
1
2
2
1
2
2
1
2
1
58
IIIa
2
1
2
0
2
2
2
2
1
0
2
1
2
2
2
2
1
1
1
0
2
1
1
3
1
1
56
0
0
1
55
54
1
1
1
2
2
3
3
4
2
3
3
3
2
2
2
1
2
1
VIIa
53
1
2
2
2
2
2
2
2
3
2
2
4
2
1
2
2
1
0
52
2
2
3
2
2
3
2
2
2
2
2
2
2
2
2
2
1
2
1
2
2
1998
62
0
2
2
2
2
2
2
2
2
2
2
3
2
3
2
2
2
1
2
59
2
2
2
3
2
2
2
2
2
2
1
2
1
IIIa
2
2
2
2
2
3
2
3
2
1
3
2
2
3
2
3
1
0
2
3
2
2
2
3
61
1
1
2
1
2
1
60
59
1
1
57
1
1
56
0
1
1
0
3
2
1
2
3
2
2
1
2
1
2
55
0
1
2
2
1
1
2
3
2
2
2
1
2
1
2
2
1
0
VIIa
53
2
2
2
1
3
2
2
2
2
2
2
2
2
1
3
2
2
2
1
2
57
2
59
IIIa
2
2
2
1
2
2
2
3
2
1
1
1
2
3
2
3
1
1
2
2
2
3
2
3
58
1
1
57
1
1
56
1
1
1
55
54
0
1
2
2
1
2
3
3
1
1
2
2
2
2
2
1
2
1
2
1
2
2
1
3
2
3
4
2
2
2
2
2
2
1
1
1
1
2
1
2
1
2
2
2
1
1
1
2
1
2
1
60
1
2
2
2
1
1
3
2
3
2
1
2
0
VIIa
53
56
1
1
1
55
54
52
1999
1
2
2
2
2
3
2
1
2
2
2
2
2
2
1
2
1
1
1
1
2
0
2
2
1
2
2
2
2
2
2
2
2
2
3
2
1
2
1
2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
52
51
50
1
2
2
2
2
2
2
2
3
1
2
3
2
3
2
2
2
2
2
49
48
47
46
2
2
2
3
2
1
4
1
2
2
2
2
1
45
IIIa 44
2
1
2
2
3
3
2
3
2
1
3
2
2
2
2
3
1
1
2
3
2
3
2
3
43
42
41
40
1 39
1 38
1 37
36
35
34
33
2000
32
31
59
1
2
2
2
2
2
3
2
3
2
1
2
1
IIIa
2
2
2
2
2
3
2
3
2
1
2
2
2
3
2
3
1
2
0
2
2
3
2
3
58
1
1
57
1
1
56
0
0
0
0
1
1
2
1
2
1
2
4
3
2
1
2
2
2
0
1
1
1
2
1
2
2
3
1
2
1
1
0
2
1
2
1
60
55
54
0
1
1
1
1
0
1
2
3
2
2
2
2
2
1
2
2
1
VIIa
53
0
1
1
1
1
1
1
1
3
1
2
2
2
2
1
2
2
1
52
2002
1
1
2
1
1
2
1
2
1
2
2
2
2
2
2
2
1
2
1
2
2
52
51
50
0
1
1
1
1
1
1
1
2
2
2
3
2
3
2
1
2
1
2
49
48
47
46
1
0
2
2
2
2
3
2
3
1
1
2
1
45
IIIa 44
1
2
2
2
2
3
2
3
1
0
1
2
1
3
2
3
1
0
0
2
2
3
2
2
43
42
41
40
0 39
0 38
0 37
36
35
34
33
2003
32
VIIf
51
-2
2
61
VIIf
51
VIIa
53
62
0
1
2
1
1
2
2
1
3
2
2
2
2
2
2
2
2
1
52
2001
VIIf
1
1
2
2
2
2
2
2
2
2
2
3
2
2
1
2
2
2
2
2
1
2
VIIf
61
0
1
1
1
2
2
2
1
2
1
2
3
1
2
1
2
2
0
2
1
1
0
1
2
2
2
2
2
2
3
2
2
3
2
1
2
2
2
2
1
3
3
1
2
2
1
3
2
3
3
2
2
2
2
1
1
1
51
62
0
1
1
0
1
2
3
1
3
1
2
1
2
2
2
2
2
1
52
-3
58
0
1
1
1
3
3
1
3
3
3
3
1
2
2
2
1
1
1
1
3
2
2
3
1
3
1
1
1
1
2
2
3
1
60
51
0
1
1
1
2
1
1
2
1
2
1
1
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
61
VIIf
62
Degrees Latitude
1
1
57
51
54
1
0
2
1
3
1
60
1
2
2
2
2
3
1
2
4
3
3
3
1
2
2
1
1
1
1
3
2
3
1
4
3
3
0
61
VIIf
58
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
31
51
-3
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
-2
-1
0
1
2
3
4
5
Degrees Longitude
27
6
7
8
9
Figure 2.5. Total number of times each statistical rectangle has been fished over the six year period
1998 to 2003.
62
E6 E7
E8
59
Degrees Latitude
F5 F6
F1
3
2
2
4
7
9
7
9
5
8
9
9
9
1
50
5
6
7
10
8
12
9
49
4
6
12
8
8
9
8
48
12 14 15 10 11 12
9
47
7
58
F3
F0
61
60
F2
E9
8
7
F4
F8
52
51
11 11 13 10
6
14 11 14 17
6
6
9
46
11 11
9
45
11 20 11 16 10 11 10 11
IIIa 44
13 15 13 10 11 10 12 10
4
5
43
6
13 13 13 12 13 13 13 12 12
7
42
6
11 10 12 13 12 10 10
57
56
F7
6
10 12
41
11 12 11 12 12 10 13 11 12
40
10
55
9
10 11 16 17 16 16 15
3
39
11 10 12 12 11
3
38
12 10 16 15 17 17 17
4
37
11 11 11
9
54
9
9
10 11 12 11 11 10
VIIa
4
53
5
8
9
6
36
7
35
11 12 12
6
52
6
34
5
33
11 10 11
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
28
Figure 2.6. Location of all MAFCONS sampling in 2003.
E6 E7
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
62
52
51
61
50
49
60
48
47
59
46
45
Degrees Latitude
58
44
43
57
42
41
56
40
39
55
38
37
54
36
35
53
34
33
52
32
2003
31
51
-3
Germany
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
Norway
Netherlands (8BT)
England
Scotland
29
Figure 3.1. The distribution of haddock biomass in each statistical rectangle, 1998 to 2003 (Red
symbols indicate interpolated data). Symbol size varies from 0 to 76,000 tonnes and is the same for all
years.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
38
54
VIIa
VIIa
37
36
VIIa
35
53
34
33
52
51
1998
1999
VIIf
2000
VIIf
32
VIIf
31
62
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
54
38
VIIa
37
36
VIIa
VIIa
35
53
34
33
52
2002
2001
VIIf
VIIf
51
-3
2003
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
Degrees Longitude
30
6
7
8
9
Figure 3.2. The distribution of whiting biomass in each statistical rectangle, 1998 to 2003 (Red
symbols indicates interpolated data). Symbol size varies from 0 to 79,000 tonnes and is the same for all
years.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
38
54
VIIa
VIIa
37
36
VIIa
35
53
34
33
52
51
1998
1999
VIIf
2000
VIIf
32
VIIf
31
62
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
54
38
VIIa
37
36
VIIa
VIIa
35
53
34
33
52
2002
2001
VIIf
VIIf
51
-3
2003
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
Degrees Longitude
31
6
7
8
9
Figure 3.3. The distribution of cod biomass in each statistical rectangle, 1998 to 2003 (Red symbols
indicates interpolated data). Symbol size varies from 0 to 20,000 tonnes and is the same for all years.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
38
54
VIIa
VIIa
37
36
35
VIIa
53
34
33
52
51
1998
1999
VIIf
2000
VIIf
32
VIIf
31
62
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
54
38
VIIa
37
36
35
VIIa
VIIa
53
34
33
52
2002
2001
VIIf
VIIf
51
-3
2003
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
6
Degrees Longitude
32
7
8
9
Figure 3.4. The distribution of Norway pout biomass in each statistical rectangle, 1998 to 2003 (Red
symbols indicates interpolated data). Symbol size varies from 0 to 45,000 tonnes and is the same for all
years.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
38
54
VIIa
VIIa
37
36
35
VIIa
53
34
33
52
51
1998
1999
VIIf
2000
VIIf
32
VIIf
31
62
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
54
38
VIIa
37
36
VIIa
VIIa
35
53
34
33
52
2002
2001
VIIf
VIIf
51
-3
2003
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
Degrees Longitude
33
6
7
8
9
Figure 3.5. The distribution of grey gurnard biomass in each statistical rectangle, 1998 to 2003 (Red
symbols indicates interpolated data). Symbol size varies from 0 to 27,000 tonnes and is the same for all
years.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
38
54
VIIa
VIIa
37
36
VIIa
35
53
34
33
52
51
1998
1999
VIIf
2000
VIIf
32
VIIf
31
62
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
54
38
VIIa
37
36
VIIa
VIIa
35
53
34
33
52
2002
2001
VIIf
VIIf
51
-3
2003
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
Degrees Longitude
34
6
7
8
9
Figure 3.6. The distribution of plaice biomass in each statistical rectangle, 1998 to 2003 (Red symbols
indicates interpolated data). Symbol size varies from 0 to 3,500 tonnes and is the same for all years.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
38
54
VIIa
VIIa
37
36
35
VIIa
53
34
33
52
51
1998
1999
VIIf
2000
VIIf
32
VIIf
31
62
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
54
38
VIIa
37
36
35
VIIa
VIIa
53
34
33
52
2002
2001
VIIf
VIIf
51
-3
2003
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
6
Degrees Longitude
35
7
8
9
Figure 3.7. The distribution of lemon sole biomass in each statistical rectangle, 1998 to 2003 (Red
symbols indicates interpolated data). Symbol size varies from 0 to 5,000 tonnes and is the same for all
years.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
38
54
VIIa
VIIa
37
36
35
VIIa
53
34
33
52
51
1998
1999
VIIf
2000
VIIf
32
VIIf
31
62
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
54
38
VIIa
37
36
35
VIIa
VIIa
53
34
33
52
2002
2001
VIIf
51
-3
2003
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
6
Degrees Longitude
36
7
8
9
Figure 3.8. The distribution of common dab biomass in each statistical rectangle, 1998 to 2003 (Red
symbols indicates interpolated data). Symbol size varies from 0 to 17,500 tonnes and is the same for all
years.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
38
54
VIIa
VIIa
37
36
35
VIIa
53
34
33
52
51
1998
1999
VIIf
2000
VIIf
32
VIIf
31
62
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
54
38
VIIa
37
36
35
VIIa
VIIa
53
34
33
52
2002
2001
VIIf
51
-3
2003
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
6
Degrees Longitude
37
7
8
9
Figure 3.9. The distribution of long rough dab biomass in each statistical rectangle, 1998 to 2003 (Red
symbols indicates interpolated data). Symbol size varies from 0 to 3,000 tonnes and is the same for all
years.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
38
54
VIIa
VIIa
37
36
VIIa
35
53
34
33
52
51
1998
1999
VIIf
2000
VIIf
32
VIIf
31
62
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
IIIa
IIIa 44
43
42
IIIa
57
41
40
56
39
55
54
38
VIIa
37
36
VIIa
VIIa
35
53
34
33
52
2002
2001
VIIf
VIIf
51
-3
2003
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
Degrees Longitude
38
6
7
8
9
Figure 3.10. Biomass (tonnes) of haddock in each statistical rectangle, 1998 to 2003.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
207 381 1010 958 254
61
60
59
Degrees Latitude
58
1228 8373 3277 4829 1667 849
50
2164 9472 7966 3863 6022 2281 878
49
48
47
3021 7526 3491 7335 2589 935 1066
5757 5110 7467 103071387210626 3191
2904 17162145391038416791 1478 1334
9787 14677 867 2828 5368 1938 182
10483 8130 2724 2878 7903 7546 3299
1519620628 3731 4067 7045 8671 987
2872 2453 706 1085 5539 2828 1777
7911 9095 5499 6309 5767 9633 5049
2252018230 6890 5716 9610 13960 1550
42 2127 11576 5131 1080 1632 891 706 1203
94 136181556712061 3293 15471 2606 6873 3714
3336 2353523665 7388 1267 3460 4122 4205 4832
399 6346 6017 283 1180 2724 1390 3399 6513
7
252 15859 6244 2011 8746 7400 16481 6429 10647
30
IIIa
6498 6178 4897 3825 1755 173 228 1191 1758 2539
272
0
391 5383 10609 7483 4686 1635 3587 964 182
60
62 5425 149 3451 744 2516 7448 13
0
64
12132 9509 6347 2647 2397 2129 1966 564
9
4
106
46
0
6451 747 1778 2674 682 161
12810 5079 386 1702
0
11805 4093 236 333
1769213189 9037 4863 10371 4693 7114 9675 6472 3064
41
570 1567313498 4784 3073 5240 7169 11811 603 4209 1433
661 6070 2221113068 9992 7446 8692 12447 1963
8
9
174
5
0
7
2
3
1
158
0
0
1068411618 1987 5774 5754 13134 31
41
40
14
1
0
0
0
5047 4363 1868
4
0
20
20
0
0
0
1868821536 3116 175
59 8670
3
8
0
0
1
0
0
0
0
0
9247 1674 199
0
4
12
0
0
0
0
15163 8334 21111 0
16
11
2
0
0
0
38
0
34
0
0
0
0
0
0
312
22
0
0
0
0
0
0
0
40100 7689 19
3
11
7
0
28
0
28
1
0
0
0
0
0
103
4
0
0
0
0
0
816
0
36
0
163
11
6
0
0
0
0
18
0
0
0
0
0
0
37
36
35
0
0
0
0
0
0
158
0
119
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
VIIa
1998
0
VIIf
14128 9
VIIa
0
0
0
1999
VIIf
61
IIIa 44
43
42
8080
VIIa
62
46
45
31 5972 1344910924 3884 2206914174 9191 4575 4050
IIIa
9785 8435 8705 5801 2400 1072 1204 3479 6745 2325
233 9186 4319 6421 1284 2321 401 537 288 261
5685 1392 6866 2771 1143
52
39
34
33
2000
32
VIIf
31
1252 1303 967
322 532 536
551 626 571
3320 1592 986 1446 545
701 368 924 553 161
552 546 546 768 384
52
51
1478 6227 806 1482 1541 1444
602 3544 2191 1305 2325 2894
354 733 1032 964 3364 2002
50
3907 2869 9408 3956 5469 3366 444
4860 6289 7587 4045 3690 8466 716
1641 6226 4339 3709 4657 2823 1318
1811712207 5419 3617 7378 6250 236
2764 12432 2669 7202 8798 20263 680
1579841422 1213 3677 5717 2434 217
17122 8088 2476 2599 2672 2607 170
17773 5563 2048 3131 7898 4758 341
1516313221 1771 3611 5079 2966 114
49
48
47
6666 18679 2609 2470 3275 4941 8233
4860 12105 5185 3813 7765 13298 3268
8502 1919515807 2337 827 2279 9003 3767 2574
664 1278826849 3280 2882 1069 4669 11074 800
60
59
Degrees Latitude
52
51
190 1647 1314 3329 9547 4541
53
6840 19103 7848 2082 17750 3138 75931 3996 6633
0
56
8
1
536 1696412692 3860 5407 10405 264
46
44
0
0
9926 6838 6435 7117 3250 14
0
19
15
0
12797 5640 11194 0
0
20
170
8
0
0
12188 5090 3630
0
29
0
39
0
0
0
12931 9225 1374
2078926334 17
9
0
0
4
0
0
6
0
0
0
0
12761 9998 1055
VIIa
53
4255
5
1085
0
52
0
106 5017
19
989 21370 8766 17249 5586 314 772 109
7889 1203516640 1203 2973 33536 2789 21
597 1393
0
1
2
4
2
36 4875 4625 11253 5338 3695 2292 74
59
2
0
33
1
47
1
0
IIIa 44
43
42
1
0
0
0
0
0
0
0
0
1
14
0
0
0
6293 9454 1067
9
0
6
2
0
0
0
0
13
0
0
0
0
0
2821 6634 1841
0
3
6
0
0
0
0
38
14849 3592
0
0
0
0
0
0
0
12714 299
0
0
6690 11
0
0
0
0
0
0
861 5319 2639 920 423
0
2
0
0
0
7851
0
0
0
0
0
0
0
0
41
40
39
0
0
0
0
0
0
0
0
0
11
0
0
0
0
0
0
0
0
34
0
2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
2001
VIIa
0
2002
VIIf
-1
4
7
37
36
35
VIIa
51
-2
500
492 2515 4318 2756 2622 3150 38207 56
62
7614 6887 6179 2979 852
VIIf
-3
737 11661 9509 4820 1398 471 3537 76
46
45
679
900 1401610888 2465 5617 4054 4586 6401 1931
14
IIIa
9195 1999012408 1171 11564 7319 264 313 2494 3831
396 2393810526 3196 2852 10767 6503
55
3784 10735 1495 1043 8447 2098 1173
671 6907 39503 2534 3856 308 8470 18
23 5819 25044 9856 3918 10798178762290010624 4680
IIIa
975 4337 7015
8985 9979 4207 3883 7358 2018 89
57
54
1836 634 2736 503 606
639 2008 3661 10022 7216 5465 2916
55
58
1472 845 1142
282 517 118 1590 580
4526 3197 3900 690 1434 1885 453
56
51
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
300 262 735
581 1355 884 296 863 843
57
54
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
98
517 594
3
4
5
Degrees Longitude
6
7
8
9
-3
33
2003
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
Degrees Longitude
39
6
7
8
9
Figure 3.11. Biomass (tonnes) of whiting in each statistical rectangle, 1998 to 2003.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
Degrees Latitude
50
350 11834 542 283 972 273 163
7119 7969 8567 15167 1312 1426 198
240 6329 4997 1279 2360 104 438
60
5594 13381 2075 797 379 448 461
14354 6900 1955 847 281 1423 232
49
48
47
182 475
5664 10932 7310 32866 416 4230 40
238 11583 4075 1736 1949 1497 753 539 782
9
36 3257 8963 9490 3454 4822 1658 912 336 940
51
522
9
643 1043 8418 10036 1273 172 348 149 530 1518 402
445 2908 14997 7451 741 263 1364 266 293
24
221
6739 941 6795 9588 3980 553 1496 98 1682 434 2625
394 722 18697 6053 3918 983 6099 1201 4080 292 112
886 471
87
86 2338 3320 687
10
31
16283 5808 529
17
69 3473 647
11
183
21390 3979 54
16
IIIa
89 7944 603 4200 1530 3070
4787 4337 281 216
34
32
5853 1305 5232 7205 345
IIIa
6273 11690 2179 2384 680 146
869 2165 1341
57
2534 4040 15193 1778 3636 3326 52
182 6532 25
5
87
317 2601 75 64967
8996 3767 708
49
175 10001 182 4804 503 22324 39
577 162 683 1620 152 30731
10419 9075 4759
1
2777 580 2260 900 409 13893 38
31
4230 634
16
10405 165 961
526
82
611
1583 31
733
1104 770 629
0
9666
1998
1964 419 2535
58
196 1628 1009 516
48
100
308 1932 2747 549 787 155 147
439 1989 32
0
228 1356 731 202 181
50
5333 14567 1081 961 301 223 483
2244 3924 2750 1219 525 1202 470
225 7415 1625 1404 1365 241 235
1869 997 2474 6025 2066 373 460 3274 2640 379
IIIa
1123 3800 3736 418 289 13462 150
12714 7678 1946 1424 663 8387 1544 32 3854 486
1695 1698 5154 1110 1022 454 1191 16 1891 286 108
46
45
354 111 11400 2851 1376 699 610 498 193
96 12280 2016 1371 1750 133 297 319
137 424 11928 6794 3623 2070 2029 2232 625 950
IIIa
93
4967 2928 3219 1309 369 460
599 5867 2852 650 828 716 798
152 1260 926
34
49
48
47
1235 9276 3512 244 561 1897 318
57
41
2266 1510 1035 619 753 176 582
82
68
104 141 518
13
50
99
1414 3593 1725 1043 823 981 973
53
52
51
267 388 886 425
3891 2998 1888 823 139 545
2390 1654 1156 2047 409 118
32
31
25
46
1079 7329 1438 908 1032 342
332 4982 6326 796 1957 523 11353 355 2499
2000
124 257 233
1951 2413 3942 856 567 455
480 1034 14780 1511 670 1444 1031 651 232
33
5717 716 1787
1999
604 670
0
761 313 722 384
34
VIIf
502 459 215
61
36
35
297 628 1510 2194015166
VIIf
62
72626 1539 32543 1461 10876 140 117
1109 3329 37 1507 49
VIIf
510 141 113
1532812327 9096 5102 10445 5903 1513 5057 15219 37
VIIa
9640 14
135
41
40
85
826 128 13340 527 7444 1292 13
VIIa
73 1139 177 797
78
1177 62013 5309 13999 3601 1882 1662 2863 12282
103
64
879
9654 7558 11
27
7274 4170 4752 967 244
1805 8361 2580 981 3120 9075 3235 1034 219
20838 4494 2578 309 816
VIIa
247 1900 8778 1622 751 546 1181 84
362 111 1841 2599 699 252 4991 12
133 6499 2544
IIIa 44
43
42
17 550
116
11
49
17
689 349 3373 3173 728 1173 64
28 6323 685 112
123 2371 4037 1868 4932 157 234 163 402 533 1164
120 142 1585 4167 1321 734 173
30
428 323 1233
3365 4035 3446 1059 2102 66
16 6170 11876 164
1667 12182 4736 1235 1933 167 111 2199 245 751
2696 6202 1663 123 1246 44
18
110 299 362
15
56
67
46
46
144 39
3855 1769 205
46
0
1442 38
55
9071 2912 6242
8
153 1703 4592 3629 8328 12492
11120 5988 5638 34
10378 6336 7300
3
4707 3454 1835 489
279701562214815 1
20 29649
4436 40646 4029 2726015283 778 434 144 57478
VIIa
78849 6222 1824012116 5444 297 160
31837 74 9247 9738 11206 2
0
0
518
73
3918 31
825
2280 71
19
21511 46
52
1138
4687 838
10705 817 4687
408 9136 80
0
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
1105 68
162
0
24
13
36
35
307
9
6
34
1581 16
7
81
89
14
33
3906 124 2681
2002
2003
32
VIIf
51
-1
47501 6
0
VIIf
-2
41
40
1550158843199872755110674 348 152 4093 2138 37
VIIa
0
0
0
3601 1419 90
0
7876 1295 1622
2001
VIIf
3532 6904 1204 492
489 477
1383 15396 2541 854 144 577
18865 5689 1150010417 8872 2205 682 1053 612
VIIa
21997 1433 1161 277 23025
53
-3
46
45
212 1166
1129 3851 8822 4699 1328 2482 21
IIIa 44
43
42
294 17506 8536 1709 2307 239 1716 665 216 1836 392
52
Degrees Latitude
4983 14360 2850 3279 1538 1547 142
4101 6513 4451 392 606 1337 539
10764 5274 1090 1610 470
56
52
51
6
7
266 2901 292 721 353 133
4847 2775 5223 4230 1268 32
24
138
256 556
1051 2845 4181 920 1177 381 157
53
54
55
248 568 165 855 7178 2162
435 11685 3703 1872 331 501 903 117
57
0
210
31
140 4260 2843 570 1080 411 1161
55
58
681
69
8667 3039 1524 368
59
71
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
48
4473 2216 5375 11301 1665 530 887 464 467 1404
60
0
78
143 425 7251 3887 1008 1047 274 549 323
56
0
207 503 381 160 199
526 1635 1172 598 2352 723 242
57
51
205 520
2147 6379 1146 1586 633 351
59
54
0
4123 2942 2596 389 207
60
58
0
625 688
68
119
61
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
30
263 343
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
6
Degrees Longitude
40
7
8
9
Figure 3.12. Biomass (tonnes) of cod in each statistical rectangle, 1998 to 2003.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
312 537
894
61
Degrees Latitude
70 2142 145
0
228 343 394 403
0
8
11
0
661
0
0
0
275
77
955 465 225 364 849
0
0
48
102 112
27
91
0
149 720
77
103 324 2308
0
58
24
90
219 550 569 518 2763 582 268 142 261
34
234 1414 234 406 241
191 429
9
331 524
71
106
18
140
944 882
69
193
0
66
748
0
224 452
11
119
0
135 340 950 460
22
96
441 188 915 653 254
0
0
0
1497 719
0
55
26
273 116 443 707 1404
59
61
65
375
0
0
59
0
46
3
38
41
1
20
0
89
75
74
0
0
74
16
0
0
0
1
998 1250
9
142
0
8
2
138
0
34
0
316
53
350
0
IIIa
0
0
710
3
4
86
171
66
56
49
48
47
0
18
46
144 448 265
10
846 562
0
7
17
61
25
214
12
216 794 1114
18
13
14
67
52
157
7
0
20
17
11
6
9
576
35
IIIa 44
43
42
66 760 1274
5
0
27
29
6
323 134
49
348
5
194
0
149 398
35
828
9
18
31
18
6
41
40
0
0
92
93
2
0
3463
0
3
487
2
30
0
969 39
42
122
7
3
39
4
915 651
55
0
16
455
28
21
0
80
38
0
25
13
63
6
6
2
50
110
12
5
109
20
4
11
0
11
0
0
908
0
0
0
137
0
61
0
6
0
16
84
72
2
0
301 139 588
0
0
0
152
0
0
0
0
15
0
252
159
24
0
1000
0
0
34
0
2261
0
66
2821
0
0
204
52
135
0
716 238
1998
0
VIIa
0
1999
103 110 135
115 359
0
110 450
40
0
577
149 204
97
181
198
608
24 1057 430 1495 109
81
1608 147 301
387
0
390 241 321 774
38
173 205 557 614 575 353
33
401 172
106 148 297 296 792
0
201 3446 189 916
0
6
0
0
245 246
41 1144 454
0
0
11
20
133 252
30
92
996 1656
5
59
13
79
254
19
23
0
0
4
27
27
99
113
0
0
0
53
36
90
12
0
108
64
34
74
95
0
149
11
133 233
8
47
176 382 192 186
24
0
48
245 132
0
0
14
40
220
0
0
0
3
12
25
89
265
11
78
46
40
200 103 1145
385
37
41
274 159 133
0
0
0
4
58
314 197 633 207
5
277
0
0
43
122
0
70
603 245
0
0
12
0
42
118 197 659 1138
1
2
0
12
22
IIIa
76
0
34
270 939
13
46
0
504 301 263
24
185
24
138
56
28
852
0
9
33
34
17
20
130 849 587
0
14
31
27
45
77
177
0
0
32
6
178
46
49 1373 48
116
14
784
10
0
0
48
48
274 197
64
0
42
0
3
191 123
7
20
75
0
402
0
13
0
80
81
0
0
0
346
11
48
3
583
145 106 168
7
0
105
11
0
0
5
0
32
27
5
1
0
186
623 461
6
0
51
21
31
0
0
0
0
18
0
14
0
19 19777
395
24
232 548
8
95
0
0
0
1
0
259
0
38
8
11
0
0
2
0
0
0
0
2478 13
0
5747
0
0
0
113
0
77
0
541
0
0
42
VIIa
0
0
0
39 1004 90
2001
3
4
5
Degrees Longitude
6
7
8
9
-3
46
45
11
71
9
5
0
IIIa 44
43
42
21
0
19
0
2
58
0
0
0
215
0
4
698 153 234
30
0
48
0
0
0
1
1045 939
0
0
0
57
0
0
0
0
38
301
63
1
2
4
388
0
0
0
103
0
60
0
0
0
17
0
0
1
0
0
37
36
35
256
0
0
170
0
0
0
1
VIIa
0
2002
VIIf
49
48
47
134 343
0
0
50
0
0
0
2
124
72
0
1
7
0
343
VIIf
0
0
6
51
-1
161 798 694 288
18
3334 648
-2
39
52
51
122 281
93 1315
2
0
110
0
8
9
52
IIIa
32
31
389 210 183
87
33
2000
VIIf
23
VIIa
30 1094
0
72
53
214
1464
511 368
469 418
46
45
0
236 151 240
55
116
0
0
0
136 3151 93
37
36
35
263 134 315 650 763 303
4
195
22
0
4
92
158 142 233 311 309 109
22
VIIf
61
50
67
96 1181 97
0
337 1074
VIIa
VIIf
205 427
62
65
11
0
59
208 146 113 442
0
174
2861 604
62
7
13
118 238 587 744
4
52
51
76
150
1089 388 562
123 187 1375 161 131
110 592 114 251
35
235
0
300 178 496 580 380
60
33
VIIa
-3
0
4529 455 193 621
52
Degrees Latitude
IIIa
0
48 8881 2033 350
89
0
53
54
213 310 681 2443
0
0
55
56
378 140 930 831 297
0
0
57
167
316 121 251 639
0
399 585 1377
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
240
6
55
59
89
72
600 330 410 802 637 118
9
60
0
259
0
56
58
0
0
421 312 438 362 164
0
0
57
51
795 273
0
233 111 177 1418 707 1212 492
0
59
54
0
309 184 477 196 571 219
167
60
58
0
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
0
41
40
39
34
33
2003
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
6
Degrees Longitude
41
7
8
9
Figure 3.13. Biomass (tonnes) of Norway pout in each statistical rectangle, 1998 to 2003.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
61
Degrees Latitude
1473 463 1343
1528 21 1436 1696 404
1562 1030 263 4599 1049
1632 629 3333 1595 133
52
51
508 233 1155 1187 709 135
59
58
196 544 2606
4211 25813 6048 3082 7522 1475 2268
49
48
47
0
2213 13510 2837 878 2296 2928
1
1082 3156 7206 2204 916 4517
1
1316 354 4049 1882 4877 6375
63 7287 14930 6221 11012 5130 3248
2
0
1343 2316 2473 6849 13 4543 5161
2
14 2038 1667 667 2093 2220 39 4672 18404
22
52
355
30
578 1269
0
1523 452 330 2831
7
902 1220 3028
23
511
1
2899 608
IIIa
97
489
2
5
0
4
60
1
0
0
1
73
15
0
0
0
0
0
0
2
63
0
230 5743
2
37
0
1
11
0
51
39
349 30341 0
1
1
0
0
0
0
0
0
0
13
256
0
126 2531 163
0
1
0
0
0
0
1
0
10
153
0
0
0
0
0
0
0
0
25
0
0
0
0
0
0
0
0
5
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
5667 45218 3
0
0
0
1
0
0
0
0
0
0
0
0
0
423
5
1880
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
39
213
0
0
0
0
0
0
0
0
38
0
0
0
0
0
0
0
0
0
0
0
0
123
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
5
0
0
0
0
0
0
0
0
0
0
0
0
0
0
37
36
35
0
0
0
0
0
0
34
0
0
0
0
0
0
0
0
0
0
VIIa
1998
0
0
VIIa
0
1999
719 1432 1957 681 210
24
6
0
0
77
11
104 5995
0
0
0
750
0
972
0
4
147 213 1801
0
0
3
0
135 7395
0
55
758 4795
0
504 2029 4913 47
781
28
186 701 811 800
1075 29
52
51
508 476
4
50
1871
49
48
47
845 5268 2116 620 1187 320
9
4380 2791
0
0
43
0
0
91
472
19
0
0
0
0
0
0
768 236
2
46
1821 207
45
2
1
0
4
1
0
0
0
0
81
1801 1787 442 892 733
IIIa
552
5
833 767 1581 40
338 316
IIIa 44
43
42
0
0
0
0
0
0
0
0
2
4
0
1124
0
0
0
0
0
0
0
0
1
2
443
0
0
0
0
0
0
10
0
3
0
8
0
0
3
431
0
55
4
0
0
0
0
0
0
0
1
0
1
2
0
0
0
0
0
0
1
0
0
0
0
0
0
1
89
260
0
2
0
0
0
0
0
11
75
169
0
0
0
0
0
0
0
41
40
0
222
0
0
0
0
0
0
0
31
16
11
0
0
0
0
0
0
0
354
6
0
0
0
0
0
0
0
0
8
4
0
0
0
0
0
0
0
0
4
2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
38
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
7
28
0
0
0
0
0
0
0
0
0
0
0
0
0
37
36
35
34
VIIa
52
0
VIIa
VIIa
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
2001
VIIf
0
2002
VIIf
51
-1
32
0
53
-2
80
756 2940 4179 3012
358 781
161 783 550 872
45
IIIa
33
2000
2108 2942 2663 384 573 422 3951
83 1421 6422 636 129 403 895
0
200 357
8
6134 507 1195 763 497
0
289 908
37
6539 1365 6891 551
0
44
276
1030 1067
9216 1504 6889 3080 3658
2302 1795
39
31
5384 1097 2503 591 162
202
41
40
VIIf
1174 305 1015 1696 119 191 1825
662 2109 4641 221
1
2
1929 4646 2095 932 2058 1110
15
0
0
168
41 3769 9771 1518 3813 2250 3267
2
1
0
0
29 2811 3607 3136 88 1289 45
4254 6332 3232 21473 2
0
5
166
198 3335 3335 4155 572 342
0
0
24
41
0
0
IIIa 44
43
42
101
622 596
315
109
638 713 719
1
950 5827
0
VIIf
880 589 9076 3249 4107 17
46
45
3184 5557
365 2700 704 8553 549
38
1509 730 583 890 590
-3
687 2039 13508 5731 316
0
61
56
2
IIIa
425 379 1562 3805 4227 158 456
0
VIIf
57
0
0
0
59
7546 1386412037 8468
0
0
VIIa
60
0
7383 20840 6420 1301 4881 3256
0
62
Degrees Latitude
1785 301 11208 2419 4309 3994 4172
1523 3782 4314 1225 3049 817
52
54
761
0
53
58
50
4278 6691 6390 6931 16090 246 964
0
55
51
5576 11604 1095 10343 2544 3558
1035 2703 5117 3053 1428 378 1463
3107 3226 2737 8120 46
27 1562 2090 5877 2334
56
4924 4142 252 4001 1849 1167
0
9
0
57
54
0
2043 2393 2264 2599 1001
60
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
966 886 489
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
39
33
2003
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
6
Degrees Longitude
42
7
8
9
Figure 3.14. Biomass (tonnes) of grey gurnard in each statistical rectangle, 1998 to 2003.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
61
Degrees Latitude
69
859
45
0
210 514 416
31
51
74
189
40
35
54
40
5
84
6
121
13
50
1
47
16
0
42
112
21
0
38
0
0
52
31
23
56
0
38
9
5
0
25
22
5
0
49
48
47
193 952 191
9
155
0
16
14
6
6
9
35
218
1
25
0
7
16
13
213 165
2
7
152 223
11
0
10
4
0
428 457
0
7
2
7
1
159
11
2
0
5
9
21
44
0
0
5
15
0
61
38
0
0
16
50
0
17
76
0
0
44
1
0
1
156
0
49
5
0
161
75
0
69
521
21
8
0
0
261 293
5
23
34
4
8
0
80
401
39
6
0
0
41
47
0
49
55
0
0
59
96
10
414 173 110
2
3
7
43
20
549
78
212
26
99
228 252 146
188 152
0
24
0
99
129 151 182
94
90
562 366
314 158 210 103 628 2419 47
2
542 606 327
144 220 701 535 1576 558
4
49
181 248 648 512 238 163 419 1257 461 804
1
276 1208 1203 811 564 1159 2369 363 946 1089
37
200 331 320 356 236 264 634 1094 311 1256
71
8
18
333
IIIa
0
195 397 134 234 150 359 389 160
696
86
107 363 134 5398 13326 435 405 1454
407 377 182 1101216645 602 341 218 1169
0
385 231 152 5443 12443 2779 640 136 479
0
147 111 1976 4431 650 251 129
447
0
118 186 754 12021 404 456 159
524
0
38
118 156
0
448
96
1963 1767 901 402
70
66
274 165
3
702 1155 358
36
28
41
104
24
18
14
24
2
0
154
4
0
0
0
0
48
63 1788 5315 496 161 217 128 513
3308 255 415 119
97
163
58
443 3082 16
53
11
35
53
18
7
10
3
41
3
0
352
0
0
0
4
VIIa
605
1998
0
VIIf
100
0
VIIa
222 192
10
10
9
5
139
0
46
59
4
29
53
51
87
99
62
95
355 1721 264
73
3
106 190
29
26
63
1
37
36
35
15
37
0
34
14
0
0
0
0
271
2
8
55
68
5
18
67
129
43
119 253
30
17
64
52
39
34
23
162
69
49
52
51
11
118 306 375 195
14
31
17
14
33
270
50
10
41
7
18
195 825
7
13
49
48
47
8
33
0
0
0
0
216
36
3
9
17
85
0
265
3
47
20
21
53
0
0
90
18
0
286 183
0
0
89
16
4
495 737
1
42
124
35
0
60
16
0
0
13
26
17
33
182
3
19
31
91
4
66
30
22
72
49
65
0
56
164
17
25
3
34
193
70
12
132
36
8
4
361 407
26
30
186
26
14
0
201 702
0
0
1
51
44
0
346 136 134 392 2028
0
0
0
0
14
74
14
433 279 227
56
121 610 978 174 469 181
36
868 804 322 241 148 533 1423 750 2249 1109
79
450 483 279 231 713 707 497 103 452 1875
40
32
11
40
35
83
70
428 148 3813 5098 260 804 885
0
669 512 1591 747 284 121
14
0
169 4521 850 138
3
7
618 274
95
163
12
0
34
0
0
52
0
0
170 1873 2742 11645 4547 4651 541 646
86
118 136 1387 547 312 316 272 160 1017 389 38
163 600 431
59
4
32
38
31
7
0
4
3
18
234
2
6
253
0
0
0
1251 4905
VIIa
0
0
0
2001
VIIf
0
1458 129 178 277 168 126
306 467
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
720 39
20
573 37
68
14
93
21
1
0
0
36
35
0
9
5
0
34
0
0
0
0
0
0
320 1019 275
VIIa
8
0
0
2002
VIIf
-2
41
40
130 262 127 351 229 2609 2538 105 233 1010
304 127 1314 2533 720 185
231 104
860
51
-3
456 371 264 181 592 534 1815 1653 878 1005
100 378 464 4853 2112 5698 779 429 346 519
805 7617 59
68
175 195 247 353 151 385 761 1946 807 768
799
276 242 192 271 390 3554 2202 600 275 559
36 1000 289 246 386 400 329 992
1177
53
IIIa
147 376 343 277 257 1024 540 1059 68
198 205 886 5748 26427 7569 656 318 1244 72
VIIa
22
12
34
119
358 512
63
303 162
45
126 567 985 583
73
439 120 108 282 224
7
55
24
46
0
176 117 203 212 747
IIIa
0
7
31
0
0
0
IIIa 44
43
42
2 1313 324 144 271 332 454 1435 413 736 914
457 230
87
32
343 294 195
12
72
57
33
2000
31
657
0
39
66
VIIf
72
172 285 138
90
925 146 474 204
1999
VIIf
62
41
40
186 247 4260 3010 4443 433 1425
23
205
52
61
0
72
704 457
62
139
78
143 1405 8053 1627 16473 1018 655 343
VIIa
59
4
19
IIIa
278 339 280 556
85
186 112 103 704 239 12191 4436 1181 527 580
60
37
222 552 947
46
45
IIIa 44
43
42
815 490 868 709 184 358 483 242 727 721
53
Degrees Latitude
87
52
51
21
25
55
54
334 141 314
118
88
56
58
7
7
57
51
583
48
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
60
59
54
76
78
60
58
316 255
14
79
33
2003
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
6
Degrees Longitude
43
7
8
9
Figure 3.15. Biomass (tonnes) of plaice in each statistical rectangle, 1998 to 2003.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
61
0
0
0
0
0
0
0
0
0
3
0
3
0
0
12
0
0
52
51
8
0
0
0
0
48
31
0
0
0
0
42
7
0
11
0
50
0
0
0
0
19
0
0
0
0
0
77
39
21
0
0
0
0
63
0
11
43
21
0
0
72
70
0
0
20
0
0
97
42
6
0
0
8
0
61
53
5
0
14
0
0
59
198
0
7
14
13
0
84
88
0
0
0
0
0
49
48
47
0
15
0
0
0
0
0
14
145
0
0
0
0
0
29
75
0
0
21
42
0
35
63
34
3
0
0
11
15
88
183
73
0
0
0
33
11
75
58
0
0
0
0
8
0
16
0
24
47
0
0
0
0
0
54
8
43
358
21
0
37
90
58
0
23
16
9
65
92
33
0
49
72
85
21
53
54
51
0
22
36
58
170
24 1111
97
0
0
18
0
9
0
43
31
109
26
0
87
15
64
31
15
147 450 367
15
203
92
13
0
60
25
98
266 3118
11
229
79
90
0
42
128
16
92
51
281
19
584 3472 1112
0
79
106
67
67
75
50
125 330 1110 2103
16
75
86
65
57
16
41
162 112 556 1128
14
48
0
83
42
227 149 262 1126
0
0
34
42
91
57
37
0
55
7
32
143 121 433 165
60
67
155 126 214 302 463 1085 677 553
66
118
42
216
62
233 394 411 472
0
196 149 148
41
99
224 341 182 667
0
48
86
0
41
223 289 116
44
137 542 296
65
139
46
IIIa
81
168 1081 1764
0
45
32
162 113 292 344 1693
118
71
36
381
39
140
33
141 225 611 1014
0
84
267 113 1414
0
2
61
90
388
87
772
10
38
283
42
111
73
120
18
32
358 141 183
70
94
106 145
58
67
107
1848 89
29
62
24
15
34
173
25
11
110
32
5
263
44
10
53
73
34
102
17
42
0
0
0
0
0
VIIa
1998
139
14
15
0
0
0
0
0
0
0
0
101
0
0
0
0
84
0
0
0
0
0
20
139
0
0
49
0
0
133 360
0
0
0
0
0
39
144
3
5
0
56
0
25
236
71
0
0
0
96
34
0
14
24
6
30
95
127
49
8
49
77
28
119 276
0
36
109 112
40
61
103 424
0
0
0
894 143
4
0
39
0
151 171
0
0
0
22
49
45
0
0
0
0
175 135
16
0
6
0
112
0
0
70
128
22
0
48
23
185
49
6
207 179
76
0
0
241
47
34
18
731 248
49
5
18
11
65
188 735 424
0
44
53
50
39
18
0
16
48
6
55
6
72
9
173 191 145 663 726
64
194
49
90
121
419 448 227
4
91
52
89
18
718 439 427 280 543
35
60
131 202 170 604 298 407 149 173
0
67
IIIa
0
19
52
69
0
0
0
50
0
0
0
0
162
81
0
0
241 375
49
48
47
20
55
0
0
0
26
32
23
0
60
16
0
77
0
8
211 189
18
0
0
56
0
74
41
101
98
7
58
50
33
191
85
214
0
17
167
30
32
84 1043 307
32
25
8
48
42
52
122
36
71
41
35
104 150 339 1900
31
10
11
58
17
143 166 110
134 574
88
52
40
45
75
339 198 550 155 326 585 427 38
103
32
70
7
17
64
80
63
65
23
94
217 467 1207
82
78
33
0
160
82
160 325 632
132 299
8
350
46
227 493 878 390 397
50
90
217 265 216 249 254 130 345
265 213 432
119 272 336 388
63
196 140
35
493
0
77
487 316
69
50
32
6
3
IIIa
244
46
21
56
0
36
85
36
35
34
152
47
90
76
36
51
80
262
15
94
0
58
19
39
376
30
317
252
2002
VIIf
3
4
5
Degrees Longitude
6
7
8
9
-3
551 626 503 800 39
146
19
278 228
41
40
26 1186
295 180 341 348 125 374 37
85
70
IIIa 44
43
42
19 559 979
167 584
122 163 574 278 120 309 444
VIIa
111
2001
45
41
0
VIIf
2
52
51
75
51
1
0
0
50
0
0
0
16
111 245 511 346 190
0
0
83
114
73
0
0
11
65
110 219
0
4
0
68
VIIa
31
96
440 225
268
164 484 284 324 1247 155
36
32
0
188 468 589
41
127 247
33
2000
VIIf
9
0
9
198
1999
0
0
0
190 350 533 154 172 401 207
VIIa
21
9
0
262
78
126 130
4
-1
96
77
63
34
-2
79
63
13
0
53
39
57
100 217 190 228 1054
0
VIIa
41
40
31
0
55
0
3
13
0
68
37
36
35
VIIf
62
-3
172
60
VIIf
56
0
49
36
10
6
8
72
146
VIIa
57
43
126
17
IIIa
209 243
135 241 200 482 213 743 338 835
59
46
45
0
17
122
60
0
IIIa 44
43
42
60 121 51 199 152
52
Degrees Latitude
0
0
53
54
0
21
55
58
0
52
56
51
0
0
16
57
54
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
67
59
Degrees Latitude
0
24
60
58
0
33
2003
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
6
Degrees Longitude
44
7
8
9
Figure 3.16. Biomass (tonnes) of lemon sole in each statistical rectangle, 1998 to 2003.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
61
60
Degrees Latitude
13
23
23
11
21
0
0
77
188
45
20
0
14
40
3
1
18
33
51
50
198 1467 53
780
8
0
3
654 885 113 124
8
3
0
36
104
0
0
137 167
86
163 198 324
46
0
66
49
32
11
455 355
34
121 169
6
89
49
36
438 435 325 273 155 173 131
14
14
56
147
21
53
217
6
5
382 116
0
12
250
69
41
344 191
0
0
114
86
30
570 408 501
51
0
240 139
69
96
313 218 280
42
0
166
34
18
87
539 251 222 230 280
46
10
40
282 299
83
621 136
25
40
72
468 637 568 292 134
86
94
108
12
54
815 276 439 251 111
91
88
67
0
133 153 169
65
16
136
19
227 463 166 375
96
176 290 132
61
IIIa 44
43
42
68
83
205
42
12
166
16
85
388 241 297
72
117 110
27
4
22
203 356 714 235 170 116
76
42
86
12
30
182 346 234 519
59
31
65
5
7
79
0
7
458 289 452
8
15
42
321 330 355 288 121
83
283
57
8
60
13
54
248 183
49
14
53
39
31
32
13
21
106 248 514 120
90
34
52
21
18
6
12
28
191
229
146
34
37
165
0
24
186 1321
330
0
0
4
0
0
108
126
70
0
0
0
16
0
0
0
0
0
0
12
82
27
14
0
0
225 361 291
45
16
86
34
0
0
0
17
9
15
6
8
0
131
20
96
0
36
11
17
6
3
0
38
25
131
0
9
4
4
1
182
0
37
174
12
10
6
18
4
132
0
4
0
57
0
0
0
12
0
11
2
0
0
0
0
37
36
35
34
0
0
4
0
38
0
0
0
0
0
0
0
0
0
0
24
0
0
53
0
0
6
0
0
0
1998
12
VIIa
0
1999
22
39
34
13
361 119
34
84
64
435 894
18
61
75
91
92
134 3996 75
188
16
45
8
225 1365 51
14
209
19
18
0
73
369 139
0
29
63
96
113
219 258 240
57
8
337
82
75
12
582 327
62
7
0
23
68
118
124
27
30
316 325 282 117
61
20
15
66
30
30
15
0
50
258
37
22
83
30
501
0
106
29
5
35
62
242 182 108
12
53
20
14
20
0
40
97
34
13
2
40
50
978
12
0
9
0
154
34
10
49
48
47
22
924 3120 102 136 225
115
31
12
0
49
430 259
0
30
443 126
63
286 328 506
45
0
166
97
8
0
250 210 337 145 241
60
44
100
326 343 449 114 191 160 100
27
447
61
IIIa
343 102 110
0
6
0
123 101
2
0
302
78
107
67
312 847
46
0
181
59
0
22
0
47
261 125 448 181
58
46
41
23
52
51
46
45
70
84
799 291 423 219 119 136 187
0
63
112 104 167 166
91
69
IIIa 44
43
42
48
399 220 104 207
72
53
77
45
180
2
18
34
225 693 194 157 196
88
104
58
8
48
27
514 341
131 102
33
9
12
10
45
36
253 490 475
99
130
75
177
13
152
3
94
216 107
48
21
0
107 126 246 460
77
12
107
25
31
247 315 239 426
98
28
57
0
1
91
308 148 518 327
97
46
142
0
0
52
84
75
41
40
73
23
248
65
28
88
25
43
0
0
243 142 142 175
6
110
26
28
0
0
384 188 353 165
94
117
85
7
1
9
44
146
0
44
6
6
30
4
0
476 127
81
62
42
0
12
6
0
11
106
85
104 290
34
10
22
2
26
21
38
62
157
0
27
5
10
13
36
23
19
47
75
119
8
81
17
34
17
33
265
32
19
10
17
32
32
30
268
7
0
0
10
8
0
85
8
10
0
5
0
10
147
37
0
0
0
0
87
70
0
3
6
0
2
9
0
0
6
0
0
0
0
0
37
36
35
40
0
0
44
0
0
0
0
0
34
0
7
0
46
0
0
0
0
0
0
0
16
0
0
0
VIIa
52
70
VIIa
32
2001
VIIf
VIIa
0
2002
VIIf
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
39
33
2003
32
VIIf
51
-1
72
212
53
-2
18
29
87
32
17
9
55
-3
33
2000
31
6
40
0
IIIa
43
39
VIIf
24
88
41
40
0
26
233 108
27
29
11
344 659 170 132
46
45
92
VIIf
77
94
7
IIIa
729
100
VIIa
145
56
57
403 518
23
0
10
49
48
47
67
31
57
50
5
53
0
825
42
49
547 4925 69
39
42
3
0
4
29
59
23
141
2
37
67
53
98
0
0
VIIf
60
342
33
77
18
51
901
52
51
3
4
136 570 720 104 164 564 109
VIIa
4
113
267 193 376 244 364 157
45
25
23
42
935
5
79
71
39
24
0
IIIa
47
60
8
28
61
Degrees Latitude
31
691
4
12
62
54
44
0
52
58
0
16
53
51
41
6
55
54
105
79
6
56
13
3
56
22
6
51
655
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
0
220
14
57
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
556 286 485
235
59
58
18
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
6
7
Degrees Longitude
45
8
9
Figure 3.17. Biomass (tonnes) of common dab in each statistical rectangle, 1998 to 2003.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
61
0
0
2
3
0
9
7
0
14
24
1
12
75
0
110 840
23
4
0
71
145 183
7
0
14
4
121
22
3
0
0
17
0
567 508
23
22
0
2
520 213
59
86
0
296 308
45
16
24
57
41
0
127
0
50
2
67
891
1
30
695 1968
4
26
66
106
0
85 1141 16
0
185 353
0
0
89
743
0
3
128
0
0
86
201
13
0
33
27
0
49
48
47
22
5
3
253 139
0
2
38
1487 1138 81
0
0
1
201
68
2
16
12
IIIa
429 1382 2239 86
816 1301 2759 651 169 1698
148 1779 2762 600
0
1020 1913 2715 2119 1192 3862
24 2440 1723 990 925 660 1360 3710
243
5
0
0
0
6
4
8
173 389
2
102 696
38
0
465
0
0
66
0
9
0
2
5
970
5
44
577
24
1
IIIa 44
43
42
107 565 1118 1675 4 1864 1613 3997 1124 1488 1077
0
41
40
633 1085 1259 1644 1979 2769 3569
23
710 239
251 1638 1020 1501 4824 2753 1646 912 5250
0
126
0
39
86 1768 1408 934 296 858 487 4311 48
38
270 3932 2469 893 136 744 1257 3569 157 37
158 858 2276 640 707 1884 1735
VIIa
682 334 655 1267
36
35
494 417 144
249 174 237
34
127 102 259
78
174 117
87
391
33
168 1474
45
29
704 3068 3962 706 598
0
606 785 1119 652 684 940 701 3040 919 1584 3103
1628 2962 6981 401 1031 4161 1399
1998
46
45
0
106 366 893 175
109 912 357
5
1999
VIIf
44
0
4
1591 368 1478 1604 410 1589 2157 11162 10
163
0
0
18
151 517 1307 3470 1075 810 1111 2587 3392 35
158 119 180
17
98
805 255 3148 1603 1025 2655 6883
23
136 2102 329 889 574
87
402
1225 699
0
IIIa
3
VIIa
81 1219
4
245 943 512
1210 254
831 564 666 681 1284 1267 2434
9
59
0
2196 2255 1488 854 637 547 125 449 483 2124 4857
VIIf
60
2728 65
526 510 247 2674 1669
0
0
52
51
26
896 3067 1550 1604 1208 1487 4172 5375 478
2
0
607 107
80 2351 2527 2020 567 571 1095 3444 1901
3
0
62
125 430 2762 4940 4837
255
4
17
6
363 849 1671 2171 1929 1779 8754
41
0
7
396
223 958 4384 970 3481 1772 1590 1639 4328 3986
VIIa
6
0
171 139
48
162
0
0
290 902 1715 1158 8480 728
61
Degrees Latitude
0
23
6
62
33
2000
32
VIIf
0
206
3
0
31
18
0
13
0
0
0
3
81
17
6
23
18
12
0
52
51
20
36
0
0
0
0
22
32
0
64
62
50
76
42
0
3
182
0
49
48
47
262 853
0
35
128
62
0
0
49
0
0
16
0
38
525
0
1
47
49
0
137 270
3
7
44
93
0
38
12
0
89
201
1
0
6
4
0
206 118
0
10
18
0
0
4
165 136
7
0
1
6
473
805 492 581
5
0
0
868
17
346
83
0
137 816
91
0
1596 7847 3048 1441 595
103 817 894 178
40
959 2206 3230 1732 3229 962
320 757 1561 362 156 2703 4894 5487 1915 1665 3384
IIIa 44
43
42
204 1750 861 327 37 2157 3547 4461 2299 6768 6830
471 153 122
91
137 631 1316 141 620 1399
1968 3232 1664 3185 1308 2716 2851 3120 753 3962 8376
806 2926 845 394 1096 3333 1345 2024 7743 5208 7592
88 1115 1495 2964 1416 2245 5151 10667
883 458 413 1081 1996 2941 1320 1556 6381 11101
624 181 235 1558 1933 4234 2294 2109 288 8120
30
50
57
33
56
144 342
55
54
0
0
91
52
58
21
9
789 926 137
53
51
4
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
10
536 2525 875 638
55
54
0
55
233 408 351 536 138
31
0
0
200 1595 2692 2794 2196 211
1665 170
0
342
2
8
84
56
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
0
27
59
Degrees Latitude
1
315 285 171
60
58
1
0
171 691 3185 108
2
393 445
0
0
1
9
0
1831 420 150
0
1
0
975
50
237
40
30
19
IIIa
16
3
4
1337
0
132 376 1681 1506 229
20
66
137
68
39
35
IIIa
46
45
1
227 759 618 1688 57
633 6343 1569 2882 3118 7064
2
184 489 322
41
40
0
87 1595 3709 5180 1655 3152 3662 17226 3079 5598
249 1475 1831 2845 2103 2444 3192 4489 1496 6909 39
3
316 113 2858 4736 1593 1041 1209 2198 2066 3646
186
331 6338 2059 2443 2501 1675 2873 8882
0
1911 1153 964 2044 1542 1801 2672 5493 3871
608 3872 8104 567 1858 6523 1317
796 4438 11940 832 1547 2876 599
VIIa
48
0
34
482
730
91
523
1166 46
141
38
12
32
52
227
514 1193 438
2001
141
2002
4
5
Degrees Longitude
6
7
8
9
-3
33
2003
32
VIIf
51
3
36
35
1799 56
VIIf
2
158 161 730 2225
807
332 337 903
1
1212 2398 3006 2262 1576 3148 1063
VIIa
369 1115 1011 1904
15
VIIf
0
57 1237 2442 4153 2022 1690 2567 10014 4548 38
323 1365 1121 1267 1607 1805 2319 1422 6030 37
660 340
1264 80
52
-1
3
2
212 615 429 209 1686 7217 2732 1938 1020 1584
0
1343 925 1521 17598 8874
-2
0
46 3671 563 2826 2877 2504 3927 8562
VIIa
-3
4
17
143 424 3817 3832 3329 1457 2711 7846 2930
201
53
86
402 326 236
64
0
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
6
Degrees Longitude
46
7
8
9
Figure 3.18. Biomass (tonnes) of long rough dab in each statistical rectangle, 1998 to 2003.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
23
61
Degrees Latitude
44
6
31
53
41
21
55
2
92
8
44
59
45
26
37
60
61
2
52
51
3
15
38
18
39
1
52
29
18
317 351 153
50
100
49
64
11
50
46
218 199 267 143 143
279 179
28
161 264 252 139
93
29
128
10
61
58
16
182 430
114
44
16
103
91
188 429 123
67
0
68
72
186 155 218
6
0
137 149 106 162 222
46
6
72
68
145 152 221
26
49
48
47
2
49
15
27
49
149
13
11
328 186 116 240 468 150
45
162
38
112 208 361
44
0
0
55
95
5
92
32
174 278
8
0
347 330
10
0
209 162
15
12
99
47
112 136
3
71
295 103 182 416
49
72
199 280 190
83
83
208 150 129 108
130 133
29
99
67
249 383 130 408
9
165 211 230 220 300 160 341 130
6
137 122 111
60
74
115 148 569 1371
0
117 330 222 370 152 306 367 566 707 410
20
26
202 449
5
57
266 106 1051 2709 902
52
168 313 114 1277 57
102 117
139
VIIa
IIIa
19
61
12 3128 456
0
227 185
28
0
0
115 208 1679
46
37
37
51
194 145 189
0
0
109
0
102
31
18
111
16
3
0
0
IIIa
153
57
21
0
11
0
8
0
0
8
6
0
0
0
0
0
0
0
0
0
192 196 1431 340 671
94
98
70
119 117
48
95
225
17
88
8
253
25
10
114
54
227 213 362
0
17
67
16
4
6
15
0
65
20
0
0
193 263 1056
73
172
62
0
0
110
129
23
0
0
0
0
0
187
0
15
0
0
0
31
0
0
0
0
0
0
0
0
0
0
0
85
221 115
10
23
98
233
98
525
96
37
265 132
80
59
137
81
194 152
32
49
132 596
34
420
247
108 166 479 1970 704
88
2
41
13
340 162 111 125 224 384 1072 1417 482
12
26
55
43
IIIa
184
3
4
32
21
0
79
15
33
15
0
2
82
0
0
53
18
0
40
8
22
27
0
0
38
75
142
0
3
61
0
0
0
0
0
0
135
2
13
0
0
37
36
0
0
0
0
0
35
0
0
0
0
34
0
0
0
0
0
0
VIIa
0
1999
15
218 224
42
58
548
60
3
14
96
65
98
107
61
162 169
50
56
70
47
34
117 321 205
62
384
0
32
16
13
20
61
69
42
77
14
49
48
47
0
2
35
45
44
170 182
5
29
222
78
28
99
76
40
0
365
83
35
228
92
31
46
160 152 260
48
87
263 184
53
215
182 102
54
89
359 831 276
84
21
29
149
41
63
44
76
62
82
207
19
71
90
96
77
22
6
5
760 136
79
89
80
74
236
101 147 295 322 144
52
20
79
241 227
83
81
729 136 165 309 150
4
0
65
8
13 1498 346 837 183
94
0
78
336 302 151 107 905 327 221 1942 163
27
580
40
0
86
374 251 167 112 436 590 891 1060 55
264 327 321 225 1915 86
22
148 150
63
94
433 382 198 830 133
14
842 116
0
10
27
23
44
35
0
0
56
0
43
49
70
39
0
0
38
31
5
3
11
20
0
0
0
0
33
1
13
0
0
0
0
37
36
0
0
0
0
0
35
0
0
0
34
0
0
0
0
0
16
269
24
0
98
96
77
0
0
86
241 489
0
0
377 201
9
0
0
196 213 353
41
18
0
52
4
52
2
0
6
136
95
28
0
18
22
16
8
0
0
38
33
323
35
2
116
1
0
0
0
32
19
0
0
32
0
0
0
0
36
2
23
0
4
0
0
6
0
2
0
0
0
0
10
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
2001
VIIa
0
2002
VIIf
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
41
40
35
27
VIIa
46
45
IIIa 44
43
42
377 431 120 125 739 295 966 662 143 116
IIIa
86
118
0
52
51
104 111
0
VIIf
-1
31
50
79
143 252 207 781 125 133 1578 101
51
32
14
42
0
33
2000
6
240 1165 417 503
52
39
10
0
53
41
40
70
0
311
76
IIIa 44
43
42
VIIf
77
VIIa
-2
246 101
189 229
29
80
0
6
1
6
18
5
50
8
136 742
55
53
49
216 569 139 1158 75
0
70
0
0
13
1
5
71
68
105 414 310 217 529 341 359 688 120
165
166
0
15
148 151
14
169 332 418 632 411 298 452 536
48
0
211 117 346
24
17
1998
45
64
0
VIIa
51
46
49
110 139 127 315 189 201 363
0
934 379
200 103
24
5
-3
187
135 739 179 235
0
18
56
88
64
VIIf
62
57
438 449
219 268 247 283 287 204 226 220 299 373 319
VIIf
59
70
42
0
60
235 130
97
10
52
Degrees Latitude
38
50
53
54
4
21
55
38
10
17
56
58
8
41
13
57
51
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
6
59
54
33
39
60
58
19
39
33
2003
32
VIIf
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
31
-2
-1
0
1
2
3
4
5
Degrees Longitude
47
6
7
8
9
Figure 3.19. Biomass estimates for each of the nine species 1998 to 2003 using the IBTS 3rd Quarter
data. (HAD is haddock, WHI is whiting, COD is Cod, NPO is Norway pout, GGU is grey gurnard,
PLA is plaice, LSO is lemon sole, CDA is common dab, LRD is long rough dab).
HAD
WHI
Biom ass (to nne s)
1200000
COD
100000
800000
80000
600000
800000
60000
400000
40000
400000
200000
0
0
NPO
0
GGU
600000
Bioma ss (ton nes)
20000
PLA
120000
40000
500000
30000
400000
80000
300000
20000
200000
40000
10000
100000
0
0
Bioma ss (ton nes)
LSO
0
CDA
30000
300000
20000
200000
LRD
40000
30000
20000
10000
100000
10000
0
0
0
1998 1999 2000 2001 2002 2003
1998 1999 2000 2001 2002 2003
1998 1999 2000 2001 2002 2003
Year
Year
Ye ar
48
Figure 3.20. Comparison of the IBTS derived biomass estimates of the five “assessed” species, cod,
haddock, whiting, Norway pout and plaice, with estimates of total stock biomass derived from VPA in
the stock assessments made by the ICES WGNSSK (ICES 2003a).
Cod
Haddock
200000
800000
1600000
700000
1200000
100000
800000
400000
0
500000
400000
200000
1998 1999 2000 2001 2002 2003
Year
Norway pout
600000
300000
0
1998 1999 2000 2001 2002 2003
Year
1998 1999 2000 2001 2002 2003
Year
Plaice
300000
TSB (Tonn es)
1200000
TSB (To nne s)
Whiting
2000000
TSB (To nne s)
300000
TSB (To nne s)
TSB (To nne s)
400000
800000
400000
0
200000
WGNSSK
IBTS
100000
0
1998 1999 2000 2001 2002 2003
Year
1998 1999 2000 2001 2002 2003
Year
49
Figure 3.21. PRIMER dendrogram: clustering of statistical rectangles which have a similar species
composition using the 1998 IBTS data. In this figure, four separate clusters are identified at a
similarity of 35%. A sub cluster with a similarity of 45% is also indicated. The symbols correspond to
those shown in figures 4.33 and 4.34.
X
X
50
Figure 3.22. Results of the cluster analysis including all fish species for each year 1998 to 2003.
Clusters ■, ●, ▲ (X, X) have a similarity of 35%, X and X are sub-clusters at a similarity of 40%.
Degrees Latitude
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
61
61
60
60
59
59
58
58
57
57
43
42
56
56
41
40
55
55
50
49
48
47
46
45
44
39
54
54
53
53
52
52
38
37
36
35
34
33
1998
1999
51
62
2000
32
31
51
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
44
57
43
42
56
41
40
39
55
38
37
36
35
54
53
34
33
52
2001
2002
32
2003
31
51
-3
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
-2
-1
0
1
2
3
4
5
6
7
8
Degrees Longitude
51
9
Figure 3.23. Results of the cluster analysis for all fish species for all six years combined. Clusters ■, ●,
▲ (X, X) have a similarity of 35%, X and X are sub-clusters at a similarity of 40%.
62
E6 E7
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
44
43
57
42
41
56
40
39
55
38
37
54
36
35
53
34
33
52
32
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
52
Figure 3.24. Results of the cluster analysis for demersal fish only for each year 1998 to 2003. Clusters
■, ●, ▲ and + have a similarity of 40%.
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
44
57
43
42
56
41
40
39
55
38
37
36
35
54
53
34
33
52
1998
1999
2000
32
31
51
62
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
44
57
43
42
56
41
40
39
55
38
37
36
35
54
53
34
33
52
2001
2002
32
2003
31
51
-3
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
-2
-1
0
1
2
3
4
5
6
7
Degrees Longitude
53
8
9
Figure 3.25. Results of the cluster analysis for demersal fish only for all six years combined. Clusters
■, ●, ▲ and + have a similarity of 40%.
62
E6 E7
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
44
43
57
42
41
56
40
39
55
38
37
54
36
35
53
34
33
52
32
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
54
Figure 3.26. Changes in average weight (g) of demersal species in each statistical rectangle from 1998
to 2003. Symbol size ranges from 0 to 627g.
Degrees Latitude
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
61
61
60
60
59
59
58
58
57
57
43
42
56
56
41
40
55
55
54
54
53
53
52
52
1998
1999
51
62
50
49
48
47
46
45
44
39
38
37
36
35
34
33
2000
32
31
51
52
51
61
50
49
48
47
60
59
46
45
Degrees Latitude
58
44
57
43
42
56
41
40
39
55
38
37
36
35
54
53
34
33
52
2001
2002
32
2003
31
51
-3
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
9
-3
-2
-1
0
1
2
3
4
5
Degrees Longitude
55
6
7
8
9
Figure 3.27. Changes in average weight (g) of demersal fish in each of the community composition
clusters.
Cluster 1
Cluster 2a
200
X
Cluster 2b
X
Average weight (g)
160
120
80
40
0
1998
1999
2000 2001
Year
2002
2003
1998
1999
Cluster 3
2000 2001
Year
2002
2003
2002
2003
1998
1999
2000 2001
Year
Cluster 4
200
Average weight (g)
160
120
80
40
0
1998
1999
2000 2001
Year
2002
2003
1998
1999
2000 2001
Year
56
2002
2003
Figure 3.28. Species richness (S) in statistical rectangles fished more than five times during the period
1998 to 2003. Symbol size ranges from 16 to 41 species.
62
E6 E7
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
57
Figure 3.29. Shannon-Wiener diversity index (H’) for statistical rectangles fished more than five times
during the period 1998 to 2003. Symbol size ranges from 0.30 to 1.93.
62
E6 E7
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
58
Figure 3.30. Simpson index (λ) for statistical rectangles fished more than five times during the period
1998 to 2003. Symbol size ranges from 0.17 to 0.88.
62
E6 E7
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
59
Figure 3.31. Hills N2 for statistical rectangles fished more than five times during the period 1998 to
2003. Symbol size ranges from 1.12 to 5.69.
62
E6 E7
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
60
Figure 3.32. Location of the Norwegian fishing stations in 2003.
62
E6 E7
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
Degrees Latitude
45
575
58
57
578
570
569
IIIa 44
565
568
574
571
573
572 567
564563
43
566
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
61
Figure 3.33. Comparison of the biomass estimates made using the Norwegian data alone and the whole
of the IBTS dataset for 14 statistical rectangles in 2003.
Ha d d ock
45000
16000
40000
Whiting
35000
Cod
900
800
14000
700
12000
600
30000
10000
500
25000
8000
20000
400
6000
15000
300
4000
10000
0
500
200
2000
5000
100
0
0
42F0 42F1 42F2 42F3 42F4 43F1 43F2 43F3 43F4 43F5 43F6 44F1 44F2 44F3
42F0 42F1 42F2 42F3 42F4 43F1 43F2 43F3 43F4 43F5 43F6 44F1 44F2 44F3
St at i st ical rect ang le
St at ist ical rect ang le
Norwa y p out
2500
G re y gurna rd
43F1 43F2 43F3 43F4 43F5 43F6 44F1 44F2 44F3
St at i st ical rect ang le
200
P la ice
180
450
400
160
2000
140
350
300
120
1500
250
100
200
1000
80
150
60
100
500
40
50
20
0
0
42F0 42F1 42F2 42F3 42F4
43F1 43F2 43F3 43F4 43F5 43F6 44F1 44F2 44F3
0
42F0 42F1 42F2 42F3 42F4 43F1 43F2 43F3 43F4 43F5 43F6 44F1 44F2 44F3
St at ist i cal r ect ang l e
400
42F0 42F1 42F2 42F3 42F4
42F0 42F1 42F2 42F3 42F4 43F1 43F2 43F3 43F4 43F5 43F6
St at ist i cal r ect ang l e
Le mon sole
7000
350
Common d a b
1200
6000
300
44F1 44F2 44F3
St at i st i cal r ect ang le
Long rough d a b
1000
5000
800
250
4000
600
200
3000
150
400
2000
100
200
1000
50
0
0
42F0 42F1 42F2 42F3 42F4 43F1 43F2 43F3 43F4 43F5 43F6
St at i st i cal r ect ang l e
NORWA Y
IB TS
44F1 44F2 44F3
0
42F0 42F1 42F2 42F3 42F4 43F1 43F2 43F3 43F4 43F5 43F6 44F1 44F2 44F3
42F0 42F1 42F2 42F3 42F4 43F1 43F2 43F3 43F4 43F5 43F6 44F1 44F2 44F3
St at ist i cal r ect ang l e
St at i st i cal r ect ang l e
NORWA Y
IB TS
NORWA Y
IB TS
62
Figure 3.34. Cumulative species curves for both the Norwegian and IBTS data, 2003.
35
Sp c o u n t ( c u mu lativ e
30
25
20
15
10
5
0
42F0
42F1
42F2
42F3
42F4
43F1
43F2
43F3
43F4
43F5
44F1
44F2
44F3
Statis tic al r ec tan g le
NORWAY
IBTS
63
Figure 3.35. Location of the Dutch 8m-beam trawl station during the 3rd Quarter, 2003.
62
E6 E7
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
1400061
50
49
1400062
60
1400063
48
1400064
47
59
1400060
14000291400030
Degrees Latitude
58
46
1400056
1400059
1400027 1400031
1400028
1400032
1400035
1400034
1400033
57
1400070
1400036
1400068
14000651400066
1400024
1400023
1400037
1400022
1400038
1400039
1400040
1400073
43
1400051
1400050
1400069
1400049
1400048
1400047
42
41
14000411400042 1400075
1400074
1400021
1400020
55
IIIa 44
1400052
1400067
1400026
1400025
56
45
1400055
1400054
14000531400072
1400058
1400057
40
1400076
1400077
39
1400043
1400019
1400044
1400018
38
1400045
1400046
1400012 1400015
14000131400014
54
37
1400017
VIIa
36
1400011
1400016
1400010
53
35
1400008
1400009
1400007
34
1400006
33
1400005
1400001
1400004
1400003
1400002
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
64
Figure 3.36. The percentage contribution to the total number of demersal fish made up by the nine
selected species (haddock, whiting, cod, Norway pout, grey gurnard, plaice, lemon sole, common dab
and long rough dab) in the GOV and the 8m-beam trawl datasets in 2003.
GOV
9 species
Starry Ray
Lesser weever
Scaldfish
Dover sole
OTHER
8m- BEAM TRAWL
9 species
Starry Ray
Lesser weever
Scaldfish
Dover sole
OTHER
65
Figure 3.37. The biomass estimate of haddock made using the GOV data subtracted from the biomass
estimates of haddock made using the 8m-beam trawl data set in each statistical rectangle. If symbols
are black than the biomass estimates made using the GOV are higher, if symbols are red then the
biomass estimates made using the 8m-beam trawl are higher.
E6 E7
62
E8
E9 F0
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
-2000 to 0
0 to 10000
10000 to 20000
20000 to 30000
30000 to 40000
66
Figure 3.38. The biomass estimate of whiting made using the GOV data subtracted from the biomass
estimates of whiting made using the 8m-beam trawl data set in each statistical rectangle. If symbols are
black than the biomass estimates made using the GOV are higher, if symbols are red then the biomass
estimates made using the 8m-beam trawl are higher.
62
E6 E7
E8
E9 F0
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-2000 to 0
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
0 to 10000
10000 to 20000
20000 to 30000
30000 to 40000
40000 to 50000
50000 to 60000
67
Figure 3.39. The biomass estimate of cod made using the GOV data subtracted from the biomass
estimates of cod made using the 8m-beam trawl data set in each statistical rectangle. If symbols are
black than the biomass estimates made using the GOV are higher, if symbols are red then the biomass
estimates made using the 8m-beam trawl are higher.
62
E6 E7
E8
E9 F0
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
-3000 to -2000
-2000 to -1000
-1000 to 0
0 to 1000
68
Figure 3.40. The biomass estimate of Norway pout made using the GOV data subtracted from the
biomass estimates of Norway pout made using the 8m-beam trawl data set in each statistical rectangle.
If symbols are black than the biomass estimates made using the GOV are higher, if symbols are red
then the biomass estimates made using the 8m-beam trawl are higher.
E6 E7
62
E8
E9 F0
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-1000 to 0
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
0 to 1000
1000 to 2000
2000 to 3000
3000 to 4000
4000 to 5000
69
Figure 3.41. The biomass estimate of grey gurnard made using the GOV data subtracted from the
biomass estimates of grey gurnard made using the 8m-beam trawl data set in each statistical rectangle.
If symbols are black than the biomass estimates made using the GOV are higher, if symbols are red
then the biomass estimates made using the 8m-beam trawl are higher.
E6 E7
62
E8
E9 F0
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-1000 to 0
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
0 to 1000
1000 to 2000
2000 to 3000
3000 to 4000
4000 to 5000
70
Figure 3.42. The biomass estimate of plaice made using the GOV data subtracted from the biomass
estimates of plaice made using the 8m-beam trawl data set in each statistical rectangle. If symbols are
black than the biomass estimates made using the GOV are higher, if symbols are red then the biomass
estimates made using the 8m-beam trawl are higher.
62
E6 E7
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
-7000 to -3000
-3000 to -2000
-2000 to -1000
-1000 to 0
0 to 1000
71
Figure 3.43. The biomass estimate of lemon sole made using the GOV data subtracted from the
biomass estimates of lemon sole made using the 8m-beam trawl data set in each statistical rectangle. If
symbols are black than the biomass estimates made using the GOV are higher, if symbols are red then
the biomass estimates made using the 8m-beam trawl are higher.
62
E6 E7
E8
E9 F0
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
-2000 to -1500
-1500 to -1000
-1000 to -500
-500 to 0
0 to 500
72
Figure 3.44. The biomass estimate of common dab made using the GOV data subtracted from the
biomass estimates of common dab made using the 8m-beam trawl data set in each statistical rectangle.
If symbols are black than the biomass estimates made using the GOV are higher, if symbols are red
then the biomass estimates made using the 8m-beam trawl are higher.
62
E6 E7
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
-8000 to -4000
-4000 to 0
0 to 4000
4000 to 8000
73
Figure 3.45. The biomass estimate of long rough dab made using the GOV data subtracted from the
biomass estimates of long rough dab made using the 8m-beam trawl data set in each statistical
rectangle. If symbols are black than the biomass estimates made using the GOV are higher, if symbols
are red then the biomass estimates made using the 8m-beam trawl are higher.
E6 E7
62
E8
F0
E9
F2
F1
F3
F5 F6
F4
F7
F8
52
51
61
50
49
60
48
47
59
46
45
58
Degrees Latitude
IIIa 44
43
57
42
41
56
40
39
55
38
37
54
36
VIIa
35
53
34
33
52
32
VIIf
31
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
-1000 to -500
-500 to 0
0 to 500
500 to 1000
1000 to 1500
1500 to 2000
74
Figure 3.46. Differences in abundance estimates of fish species based on catches of the GOV and 8mbeam trawl.
Roundfis h
3000000
To tal n o
2500000
2000000
1500000
1000000
500000
0
Cod
Norway pout
Haddock
Grey gurnard
GOV
Lesser weever
Whiting
8m BT
Flatfis h
2000000
1800000
1600000
To tal n o
1400000
1200000
1000000
800000
600000
400000
200000
0
Solenette
Dover sole
Plaice
Long rough
Common
dab
dab
GOV
Lemon sole
Scaldfish
8m BT
75
Figure 3.47. Cumulative species curves for both the Dutch 8m-beam trawl and the GOV in 2003.
80
Sp c o u n t ( c u mu lativ e
70
60
50
40
30
20
10
0
Statis tic al r ec tan g le
8BT
GOV
76
Figure 3.48. Species diversity (S) in statistical rectangles fished using both the 8m-beam trawl and the
GOV in 2003.
Range 2 to 28
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
61
52
51
50
49
48
47
46
45
IIIa 44
43
11
42
41
13
18
40
39
38
37
36
35
34
33
8m BT 32
21
19
60
14
14
Degrees Latitude
59
58
17
17
22
18
13
17
57
56
14
23
17
15
21
18
15
24
16
14
19
13
13
14
14
13
16
55
54
VIIa
16
14
11
11
10
13
12
12
11
11
12
10
10
10
9
13
10
13
12
16
11
13
8
14
13
53
10
10
6
11
8
10
10
12
10
11
9
24
21
52
21
22
2003
VIIf
51
-3
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
31
9
62
61
20
28
60
19
20
59
Degrees Latitude
62
Range 6 to 24
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
58
17
9
20
13
18
26
57
56
11
15
26
27
24
19
14
16
19
17
18
14
16
19
23
17
15
55
54
VIIa
24
10
11
18
12
19
13
13
13
17
18
12
12
14
15
14
16
17
18
22
20
18
2
17
12
53
13
11
12
17
14
12
15
15
17
15
12
16
12
19
20
16
52
23
14
2003 31
VIIf
51
-3
52
51
50
49
48
47
46
45
IIIa 44
43
42
41
40
39
38
37
36
35
34
33
GOV 32
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
77
Figure 3.49. Shannon-Weiner (H’) in statistical rectangles fished using both the 8m-beam trawl and
the GOV in 2003.
Range 0.58 to 2.56
52
51
50
49
48
47
46
45
IIIa 44
43
42
41
40
39
38
37
36
35
34
33
8m BT 32
61
60
Degrees Latitude
59
58
57
56
55
54
VIIa
53
52
2003
VIIf
51
-3
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
31
9
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
50
49
48
47
46
45
IIIa 44
43
42
41
40
39
38
37
36
35
34
33
GOV 32
61
60
59
Degrees Latitude
62
Range 0.27 to 1.89
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
58
57
56
55
54
VIIa
53
52
2003 31
VIIf
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
78
Figure 3.50. Simpson index (λ) in statistical rectangles fished using both the 8m-beam trawl and the
GOV in 2003.
52
51
50
49
48
47
46
45
IIIa 44
43
42
41
40
39
38
37
36
35
34
33
8m BT 32
61
60
Degrees Latitude
59
58
57
56
55
54
VIIa
53
52
2003
VIIf
51
-3
Range 0.21 to 0.90
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
31
9
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
50
49
48
47
46
45
IIIa 44
43
42
41
40
39
38
37
36
35
34
33
GOV 32
61
60
59
Degrees Latitude
62
Range 0.11 to 0.73
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
58
57
56
55
54
VIIa
53
52
2003 31
VIIf
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
79
Figure 3.51. Hill’s N2 in statistical rectangles fished using both the 8m-beam trawl and the GOV in
2003.
52
51
50
49
48
47
46
45
IIIa 44
43
42
41
40
39
38
37
36
35
34
33
8m BT 32
61
60
Degrees Latitude
59
58
57
56
55
54
VIIa
53
52
2003
VIIf
51
-3
Range 1.11 to 4.85
-2
-1
0
1
2
3
4
5
Degrees Longitude
6
7
8
31
9
62
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
52
51
50
49
48
47
46
45
IIIa 44
43
42
41
40
39
38
37
36
35
34
33
GOV 32
61
60
59
Degrees Latitude
62
Range 1.36 to 8.42
E6 E7 E8 E9 F0 F1 F2 F3 F4 F5 F6 F7 F8
58
57
56
55
54
VIIa
53
52
2003 31
VIIf
51
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
Degrees Longitude
80