SEC(2007) 467

COMMISSION STAFF WORKING DOCUMENT

REPORT OF THE FIRST MEETING OF THE SUBGROUP ON MANAGEMENT OF STOCKS . ( SGMOS-05-01) OF THE SCIENTIFIC, TECHNICAL AND ECONOMIC COMMITTEE FOR FISHERIES (STECF) LONG-TERM MANAGEMENT STRATEGIES FOR BAY OF BISCAY SOLE, CELTIC SEA COD AND ANGLERFISH VIIIC-IXA Lisbon, 26-30 September 2005

This report has been evaluated and endorsed by the Scientific, Technical and Economic Committee for Fisheries (STECF) in its plenary session of 7-11 November 2005

This report does not necessarily reflect the view of the European Commission and in no way anticipates the Commission’s future policy in this area.

Contents

STECF EVALUATION AND ENDORSEMENT. SUSTAINABLE EXPLOITATION RULES FOR BAY OF BISCAY SOLE, CELTIC SEA COD AND ANGLERFISH IN ICES DIVISIONS VIIIC AND IXA 4

Background and target reference points for long-term management 4

STECF Comments and Recommendations 4

Celtic Sea cod 4

Bay of Biscay sole 4

Anglerfish in Divisions VIIIc and IXa. 5

References 5

1 INTRODUCTION 6

1.1 TERMS OF REFERENCE 7

1.2 PARTICIPANTS 8

2 CELTIC SEA COD 9

2.1 THE FISHERY 9

2.2 THE ASSESSMENT 10

2.3 THE MANAGEMENT 11

2.4 MANAGEMENT STRATEGY SIMULATIONS 12

2.5 PROJECTIONS 13

2.5.1 Settings 13

2.5.2 Results 16

2.5.3 Comments 19

3 BAY OF BISCAY SOLE 20

3.1 THE FISHERY 20

3.2 THE ASSESSMENT 20

3.3 THE MANAGEMENT 20

3.4 LONG TERM MANAGEMENT STRATEGIES 22

3.5 PROJECTIONS 23

3.5.1 Settings 23

3.5.2 Results 26

3.5.3 Comments 26

4 IBERIAN ANGLERFISH 29

4.1 THE FISHERY 29

4.1.1 Mixed fisheries 31

4.2 THE ASSESSMENT 31

4.3 THE MANAGEMENT 32

4.3.1 TACs 32

4.3.2 Relevant gear regulations and minimum landing sizes 32

4.3.3 Closed areas and seasons 33

4.4 LONG TERM MANAGEMENT STRATEGIES 33

4.5 PROJECTIONS 34

4.5.1 Settings 34

4.5.2 Results 35

4.5.3 Comments 37

5 ADVICE 39

5.1 CELTIC SEA COD 39

5.1.1 Conditions 39

5.1.2 Management plan 39

5.1.2.1 HCR 39

5.1.2.2 Technical measures 39

5.2 BAY OF BISCAY SOLE 40

5.2.1 Conditions 40

5.2.2 Management plan 40

5.3 IBERIAN ANGLERS 40

5.3.1 Conditions 40

5.3.2 Management plan 41

6 REFERENCES 42

7 ANNEX 1 - CELTIC SEA COD 43

7.1 ESTIMATION OF STARTING POPULATION NUMBERS FOR CELTIC SEA COD IN 2005 43

7.2 DETAILED RESULTS OF CS5 SIMULATIONS 44

7.3 F-PRESS SIMULATIONS 44

8 ANNEX 2 – BAY OF BISKAY SOLE 62

9 ANNEX 3 – IBERIAN ANGLERFISH 78

9.1 FLEETS 78

9.2 DISTRIBUTION AND ABUNDANCE 79

9.3 SIMULATIONS 81

9.4 REFERENCES 96

STECF evaluation and endorsement. SUSTAINABLE EXPLOITATION RULES FOR BAY OF BISCAY SOLE, CELTIC SEA COD AND ANGLERFISH IN ICES DIVISIONS VIIIC AND IXA

STECF was asked the following:

To deliver an opinion on the work done by a Subgroup on management of stocks (SGMOS-05-01) which met in Lisbon, 26-30 September 2005 to evaluate “Long-term Management strategies for Bay of Biscay sole, Celtic Sea cod and anglerfish in VIIc-IXa.

Background and target reference points for long-term management

In the absence of agreed long term management strategies that lead to safe biological levels, the study group considered Fmax as a proxy for a long term target conservation reference point for Celtic Sea cod and Bay of Biscay sole and Fmsy in the case of anglerfish in VIIc and IXa.

The Group carried out 3 standard projections, to be used as references: (i) projection at Fsq, (ii) projection at constant catch, (iii) projection with a 10% reduction every year until F reaches Fmax/Fmsy.

STECF Comments and Recommendations

Celtic Sea cod

STECF notes that the 2005 cod VIIe-k assessment was not accepted by ICES due to a recent deterioration in data quality. The main issues were un-quantified high-grading of catches since late 2002, unreported catch, the absence of a time-series of discards estimates, and specific concerns over the commercial and research vessel CPUE data.

As a result projections were carried forward using population numbers in 2003 with fishing mortalities in 2004 and 2005 predicted from trends in fishing effort of the main fleets.

Council Regulation (EC) No 27/2005, Annex III, part A 12 (b) prohibited fishing in ICES rectangles 30E4, 31E4 and 32E3 during January-March 2005 was assumed to have resulted in an approximately 10% reduction in F on cod in 2005, based on the analysis by Ifremer (Biseau, 2005).

STECF notes that these procedures may give an over-optimistic estimate of the number of years it will take to reach Fmax.

The projections indicate that a constant-catch strategy with catches below 6,000t gives a high probability of SSB falling below Blim and is not an appropriate strategy.

Progressively reducing fishing mortality by 10% annually until Fmax is reached would result in a gradual increase in median landings until 2010 at around 11,600t with a high probability of SSB remaining above Blim. However STECF notes that results are very sensitive to assumptions regarding the starting populations and initial assumptions about fishing mortality. A combination of smaller initial stock size and reduced future recruitment results in declining landings for the first 5 years and a large risk of SSB falling below Blim.

Although a 15% variation in TAC constraint was not explored in combination with a progressive reduction in F, the simulations that were undertaken indicate that TAC variations were within the range of year-to-year variations that occurred in the past.

STECF further notes that although progressively reducing fishing mortality by 10% annually until Fmax is reached is conditional on the correctness of the assumptions for the early years of the projection and the lack of any implementation error.

Therefore STECF advises that in reality, progressive annual reductions in F well in excess of 10% will probably be required to reach Fmax.

Bay of Biscay sole

STECF notes that Fmax for this stock is well defined at 0.20 with acceptable variability between years (0.02 for the last 5 years). In the absence of any specific management objective, STECF proposes Fmax as a target reference point for a long-term management strategy.

SSB for Bay of Biscay sole in 2004 is estimated to be lower then Bpa and fishing mortality in 2004 is estimated to be at about Fpa. However, status quo fishing mortality (average over 2000-2004) is above Flim. Therefore measures to reduce fishing mortality and increase biomass in the short term are desirable.

Maintaining fishing at status quo fishing mortality would bring SSB further down to a level where the population dynamics are unknown. STECF notes that this is a high-risk strategy and does not recommend it.

Simulations suggest that the stock can sustain landings at a level, similar to the 2005 TAC. Since median SSB is predicted to maintain SSB below Bpa, this strategy is not compatible with the precautionary approach.

STECF recommends that taking into account the precautionary approach, in order to ensure that SSB reaches Bpa in the short term; a significant reduction in F is required. In the longer-term subsequent gradual but less severe F reductions towards Fmax might be more acceptable.

STECF notes that there are no options presented with realistic implementation error that result in achieving Fmax within 10 years. STECF considers that it cannot recommend an appropriate minimum annual reduction in F as part of a sustainable HCR.

Anglerfish in Divisions VIIIc and IXa.

As anglerfish are caught in a mixed fishery with Hake, Megrim, Norway Lobster and other species, Recovery Plans of Southern Hake and Iberian Norway lobster stocks is expected to have some impact on the anglerfish catches.

A non-equilibrium production model (ASPIC) is used as assessment tool. It is apparent that fishing mortality has been over Fmsy for the whole data series and SSB shows a decrease since the beginning of the time series with recent values at about 50% of Bmsy. The assessment indicates that a 57% reduction in fishing mortality is required to bring F at Fmsy. The ASPIC model is not a good estimator of short-term changes in F and SSB, hence STECF is uncertain that the implied recent changes in F have been reliably estimated.

Several evaluations were undertaken, changing fishing mortality and varying the input parameters for projections covering a 50-year period.

Maintaining fishing at status quo fishing mortality SSB is predicted to continue to decline further below Bmsy and would bring SSB further down into unknown population dynamics and therefore not recommended by STECF as an appropriate management strategy.

Simulations indicate that in a “most optimistic” reducing F-scenario, there is a 50% probability that the decline in SSB will be reversed only in the next 2-7 years and that SSB is not expected to reach Bmsy within three decades.

With no fishing after 2005, biomass will increase at around 10%, 20% or 30% depending on the assumed input parameter and will reach Bmsy level in 2013-2012-2011 respectively.

Given the uncertainties in input parameters used for simulation and the current status of anglerfish in VIIIc-IXa, STECF strongly recommends that a substantial reduction in fishing mortality is needed as soon as possible. STECF notes that even with zero catches of anglerfish in VIIc-IXa after 2005, there is less than a 50% probability of achieving Bmsy by 2011.

Given the current state of the stock and the absence of clear objectives relating to the desired rate of stock recovery, STECF is unable to advise on an appropriate long-term management strategy.

STECF notes that regulating F with days at sea for static gears is unlikely to be an effective instrument. Anglerfish in VIIIc-IXa are taken in about equal amounts by static gears and trawl fisheries.

References

ICES, 2006a. Report of the Working Group on the Assessment of Hake, Monk and Megrim. ICES CM 2006/ACFM:01.

ICES. 2006b. Report of the Working Group on the Assessment of Southern Shelf Demersal Stocks. ICES CM 2006/ACFM: 03.

BISEAU, 2005 Working document to the 2005 Working Group on the Assessment of Southern Shelf Demersal Stocks - Effect of the Cod closure (ICES rectangles 30E4, 31E4, 32E3) in the Celtic Sea on the fishing behaviour.

INTRODUCTION

The definition of long term management strategies (LTMS) that lead stocks to safe biological levels were considered for Celtic Sea cod, Bay of Biscay sole and Iberian anglerfish. This level is commonly accepted to be Bmsy, the biomass that will produce the highest yield on the long term. During the World Summit on Sustainable Development on Johannesburg (2nd to 4th September 2002) an international commitment was achieved to drive stocks to this level. Fishing mortality that keeps stocks at Bmsy level, Fmsy, can be estimated by Fmax (the fishing mortality rate that would produce the highest yield per recruit if adequate recruitment is maintained) or by F0.1 (a fishing mortality close to Fmax but at which the risks of depleting the stock are lower). At this fishing mortality levels yield will be stable, fishing costs will be lower and the risks of bringing the stock to levels were its dynamics are unknown will be lower.

The long term target conservation reference point considered for Celtic Sea cod and Bay of Biscay sole was Fmax. In the case of anglerfish Fmsy was used as a long term target.

The stocks studied during this meeting are caught in mixed fisheries. The effect on the other stocks of the LTMS proposed were not considered due to lack of time and data. The possible effect of the recovery plans for Southern hake on Iberian anglers LTMS was explored.

These stocks are caught by different fleets, mainly trawlers and netters, but also small scale fleets, like it is the case of Bay of Biscay sole and Iberian anglerfish. For each stock a table was included with the partition of the landings by fleet and country that should help to address the impact of each LTMS by fleet.

During this meeting it was considered that implementation options would be difficult to address due to the lack of information and time. On the other hand implementation issues would probably be better addressed in a wider audience including the administration and stake holders. However some general statements are important to take into consideration:

• TAC regulation does not accomplish the objective of fishing mortality management due to discards practices and misreporting. A TAC reduction can simply have the effect of increasing these practices.

• It was considered that a reduction in effort will reduce fishing mortality accordingly, which may not be correct if changes in fishing strategies or catchability occur.

• Management of effort for netters must assure that the length and time at sea of the fishing nets can be limited during usual fishing periods. Regarding this need, a limited number of fishing days may not be sufficient to reduce fishing mortality if the vessels stay in the harbour when the catchability of fixed nets is low, else if the length of nets used by a fishing boat can be increased during fishing periods or if the nets continue to fish during the periods vessels stay at the harbour.

Taking these into account, the group considered that an effort control system should be used to effectively reduce fishing mortality, which can be implemented through several actions including: direct control of fishing effort (e.g. reduce fishing activity by x days per month), decomissioning, technical measures like closed areas and/or periods, changes in gear selectivity, etc.

The work carried out during the meeting was developed using some recommendations from SGMAS(2004) in particular on the construction of the information base, the projection definitions (Sec 2.5.1, 3.5.1 and 4.5.1) and the conditions of the LTMS (sections 5.1.1, 5.2.1 and 5.3.1).

The group agreed on using the 2005 ICES assessments as a basis for the projections studies. Celtic Sea cod and Bay of Biscay sole are assessed on the Working Group on the Assessment of Southern Shelf Demersal Stocks (WGSSDS) (ICES 2006b) and Iberian anglerfish are assessed on the Working Group on the Assessment of Hake, Monk and Megrims (WGHMM) (ICES 2006a).

It was agreed that 3 standard projections should be carried out to be used as references: (i) project at F statu quo, (ii) project at constant catch, (iii) project with a 10% reduction every year until F reaches Fmax. These results are presented in the Annexes. A set of exploratory runs was performed until an acceptable LTMS was identified. Using these LTMS the most critical parameters were identified and sensitivity analyses of the LTMS to these parameters were performed.

The LTMS developed are composed of an HCR and technical measures. The HCR defines an operational procedure to take fishing mortality to long term target conservation reference point and must be considered under the conditions stated.

In Sections 2-4 a small description of the fishery, assessment and actual management together with the settings and results of the projection studies for each stock are presented.

Advice is given in section 5. For each stock the LTMS proposed was defined by an HCR and technical measures which have to be considered within the set of conditions stated.

The software available was CS5, F-PRESS and CP (v0.5) (code in Annex). These have some constraints that are documented in each section but did not constitute a major constraint for projections studies.

Terms of Reference

The meeting was held at IPIMAR in Lisbon (26-30 September 2005). The terms of reference, supplied by the STECF, were as follows:

Background

1. Advice is requested concerning targets for sustainable exploitation, and harvesting rules for catch and/or fishing effort limits for Bay of Biscay Sole, Celtic Sea Cod and Anglerfish in ICES Divisions VIIIc and IXa.

2. Such targets and harvest rules should be commensurate with conservation status of the stocks. The rules should also be based on the precautionary principle (in that the absence of adequate scientific information should not be used as a reason for postponing or failing to take management measures to conserve the stocks concerned).

The detailed request

(1) STECF is requested to evaluate a range of harvest rules for the stocks named in paragraph 1. with respect to medium and long term yield, stability of yield and effort and stock status with respect to safe biological limits. Evaluations shall in the first instance be made on a single species basis but the experts shall, to the extent possible, quantify mutual compatibility of the rules for the target species with the conservation needs of other species caught in the same fisheries.

The types of harvest rule to be considered shall include:

(a) Target conservation reference points, and (where appropriate) limit reference points.

(b) Harvest rules where TACs and/or fishing effort are derived according to a target fishing mortality, supplemented with a rule for reducing the mortality if the spawning biomass is below a trigger level, to ensure avoiding a limit value for the spawning biomass.

(c) Harvest rules as in (a) but including an additional constraint on the year -to-year variation of the TAC including a 15% limit on TAC variation.

(d) Evaluate alternative approaches to limit the year-to-year changes in TAC as considered appropriate.

(e) Where available data are not adequate to estimate stock size and fishing mortality by conventional techniques, identify adaptive harvest rules (such as those directly based on survey data) that are appropriate to reaching the conservation objectives.

(2) STECF is requested to advise whether effort management is necessary to achieve the effective implementation of the harvest rule and the attainment of conservation targets.

(3) The rules shall be evaluated through simulations that take into account the variability and uncertainties considered appropriate by the scientists following the guidance provided in the ICES SGMAS study group report. (Ref)

(4) The performance of the rules shall be evaluated both with respect to the perceived state of the stock and to the state of the underlying operating model population. The performance criteria shall include:

• Compatibility with the precautionary approach and relevant international standards and agreements.

• Probability distributions of yield, TACs, spawning stock biomass and fishing mortality and (where relevant) fishing effort.

• Year to year variation in TACs, yield, spawning stock biomass and fishing mortality.

• The risk of entering rebuilding situations in simulations without the year-to-year limitations in TAC change.

(5) Evaluations shall show the robustness of the harvest rules in assuring stock recovery and maintaining stocks inside safe biological limits, considering a plausible range of scenarios.

Participants

The participants are listed below:

Scientific Experts

Name | Address | Email |

Ernesto Jardim (chairman) | IPIMAR, Instituto Nacional de Investigação Agrária e das Pescas - IPIMAR Av. Brasilia 1449-006 Lisboa Portugal | Ernesto@ipimar.pt |

Rafael Duarte | IPIMAR, Instituto Nacional de Investigação Agrária e das Pescas - IPIMAR Av. Brasilia 1449-006 Lisboa Portugal | rduarte@ipimar.pt |

Jorge Landa | IEO, Instituto Español de Oceanografía, Promontorio San Martín, s/n 39004 Santander. Spain | jorge.landa@st.ieo.es |

Michael Armstrong | CEFAS, Lowestoft Laboratory Pakefield Road Lowestoft Suffolk NR33 0HT England, UK | m.j.armstrong@cefas.co.uk |

Sara-Jane Moore | Fisheries Science Service, Marine Institute, Galway Technology Park, Parkmore, Galway, Ireland | sara-jane.moore@marine.ie |

Wim Demaré | CLO – Sea Fisheries Department, Ankerstraat, 1 8400 Oostende Belgium | wim.demare@dvz.be |

Alain Biseau | IFREMER, Station de Lorient 8, rue François Toullec, 56100 Lorient, France | alain.biseau@ifremer.fr |

Gerard Biais | IFREMER, Station de La Rochelle. BP 7. FR-17137, L'Houmeau, France | gerard.biais@ifremer.fr |

EU-Commission

Name | Address | Email |

Ken Patterson | EU Commission, DG Fish, J 99, 1049 Brussels, Belgium | Kenneth.Patterson@cec.eu.int |

Hendrik Doerner | EU Commission, DG JRC, TP 266, Ispra, Italy | hendrik.doerner@jrc.it stecf-secretariat@jrc.it |

CELTIC SEA COD

The fishery

Cod in Divisions VIIe-k are taken as components of catches in mixed demersal fisheries. The reported landings since 2000 have been made principally by France, UK, Ireland and Belgium (Table 2.1). The bulk of the catch is taken by France (~75%).

Table 2.1. Percentage composition of official records of VIIe-k cod landings for the years 2000-2004, by country and gear type, as supplied to the STECF 2005 meeting on cod recovery.

COUNTRY | GearReg | % |

BEL | Beam >=80mm | 2.2 |

BEL | Other | 0.3 |

UK | Beam >=80mm | 2.0 |

UK | DemTrawl >=100mm | 0.73 |

UK | DemTrawl 70-99mm | 1.92 |

UK | Static | 2.1 |

FRA | Other | 76.7 |

FRA | Static | 0.7 |

IRL | Other | 11.5 |

IRL | Static | 1.8 |

The French fleets consist of French gadoid and French Nephrops trawlers operating in VIIf,g,h. Prior to 1980, the French gadoid trawlers also fished for hake in the Celtic Sea. Fishing effort by French gadoid trawlers has decreased since 2000. This fleet has contributed 40% on average (1983-2004) to the international landings. Most cod landed by Irish vessels are taken by trawlers (~90%) and gillnets (~10%). The UK cod landings are distributed fairly evenly across demersal trawlers, beam trawlers and static gears. Most of the Belgian landings are made by beam trawlers.

Landings compiled by WGSSDS (ICES 2006a) by country and gear are presented on Table 2.2.

Table 2.2. Nominal landings of Cod in Divisions VII e-k used by the Working Group.

Year | Belgium | France | Ireland | UK | Others | Total |

1971 | 5782 |

1972 | 4737 |

1973 | 4015 |

1974 | 2898 |

1975 | 3993 |

1976 | 4818 |

1977 | 3058 |

1978 | 3647 |

1979 | 4650 |

1980 | 7243 |

1981 | 10596 |

1982 | 8766 |

1983 | 9641 |

1984 | 6631 |

1985 | 8317 |

1986 | 10475 |

1987 | 10228 |

1988 | 554 | 13863 | 1480 | 1292 | 2 | 17191 |

1989 | 910 | 15801 | 1860 | 1223 | 15 | 19809 |

1990 | 621 | 9383 | 1241 | 1346 | 158 | 12749 |

1991 | 303 | 6260 | 1659 | 1094 | 20 | 9336 |

1992 | 195 | 7120 | 1212 | 1207 | 13 | 9747 |

1993 | 391 | 8317 | 766 | 945 | 6 | 10425 |

1994 | 398 | 7692 | 1616 | 906 | 8 | 10620 |

1995 | 400 | 8321 | 1946 | 1034 | 8 | 11709 |

1996 | 552 | 8981 | 1982 | 1166 | 0 | 12681 |

1997 | 694 | 8662 | 1513 | 1166 | 0 | 12035 |

1998 | 528 | 8096 | 1718 | 1089 | 0 | 11431 |

1999 | 326 | 6820 | 1883 | 897 | 0 | 9926 |

2000 | 208 | 4690 | 1302 | 744 | 0 | 6944 |

2001 | 347 | 5914 | 1091 | 838 | 0 | 8190 |

2002 | 555 | 6897 | 694 | 618 | 0 | 8764 |

2003 | 136 | 5018 | 517 | 346 | 0 | 6017 |

2004* | 153 | 2299 | 647 | 282 | 0 | 3381 |

* provisional |

Scaled landings 1971-1987 (SSDS WG 1999) |

The assessment

The XSA assessment of this stock is based on estimates of landings at age and trends in abundance given by commercial CPUE data and two series of French and UK trawl survey data (ICES 2006). Data on discards are presently inadequate for inclusion in the assessment. The French gadoid fleet has a strong influence on the assessment both in terms of catch numbers and CPUE.

The early part of the assessment time series (1970s) is characterised by relatively low estimates of landings, recruitment and SSB (Fig. 2.1). A 20-year period of elevated recruitment, with some very strong year classes (particularly in 1986) resulted in an increase in SSB and landings, but also a progressive increase in fishing mortality which exceeded Fpa continuously from the late 1980s. More recently, the 2001 to 2003 year classes are estimated to be well below average.

In 2005, the working group assessment was rejected by the Review Group of ACFM due to a recent deterioration in data quality. The main issues were un-quantified high-grading of catches by French vessels since late 2002, under-reporting that may be suspected when TACs become more restrictive, absence of a time-series of discards estimates, and specific concerns over the commercial and research vessel CPUE data used for XSA tuning.

As the 2005 ICES assessment for this stock was rejected, an alternative procedure for estimating starting populations in 2005 for the simulations was developed, avoiding the problems caused by high-grading of catches in 2003 and 2004 (Annex 1.1). This involved a forward projection from population numbers in 2003 given by an XSA run terminating in 2002, with fishing mortalities predicted from trends in fishing effort of the main fleets. This analysis showed a decline in F from an average of 0.85 for 2000-2002 to 0.68 in 2003 and 0.61 in 2004. SSB in 2005 is estimated to be above Bpa, whilst F is at or slightly below Fpa in 2003&2004. To examine the sensitivity of the LTMS simulations to this forecast, an alternative “pessimistic” XSA forecast was carried out assuming status quo F (0.85) in 2003 and 2004. This forecast gives SSB in 2005 between Blim and Bpa, and F in 2003&2004 above Fpa.

[pic]

Fig. 2.1. Cod in VIIe-k: Summary plots for the XSA assessment used to generate starting values for management strategy simulations. Bars and bold lines give the XSA results for data to 2002; the thin lines indicate the results of the 2005 WG assessment which was rejected by the ACFM Review Group. Open bars for recruitment in 2003 and 2004 are from RCT3.

The management

A TAC is in place for ICES areas VIIb-k, VIII, IX, X, and CECAF 34.1.1(1), which does not correspond to the stock area (VIIe-k). In 2004 and 2005 TACs were set at 5 700 and 6 200 t. Technical measures applied to this stock are a minimum mesh size for beam and otter trawlers in Sub-area VII and a minimum landing size (MLS) of 35 cm. The MLS for Belgian trawlers is 40 cm.

Council Regulation (EC) No 27/2005, Annex III, part A 12 (b) prohibited fishing in ICES rectangles 30E4, 31E4 and 32E3 during January-March 2005. This prohibition did not apply to beam trawlers during March. Council Regulation (EC) No 1954/2003 established measures for the management of fishing effort in a ‘biologically sensitive area’ in areas of VIIb, VIIj, VIIg and VIIh. Effort exerted within the ‘biologically sensitive area’ by the vessels of each EU Member State may not exceed their average annual effort (calculated over the period 1998-2002).

From the beginning of 2003, French trawlers were subject to trip landing restrictions. Penalties were imposed when landings from a trip were above the level of limitation. The restriction was suspended from May 2005 due to reduced catch rates. French vessels were also prohibited from landing the smallest size categories of cod from 2003. These two management controls were responsible for an increase in discarding due to high-grading of catches.

Management Strategy Simulations

Limit and precautionary reference points

Precautionary reference points for this stock are as follows (ICES, 2006):

Blim = 6,300 t Bpa = 8,800 t

Flim = 0.90 year-1 Fpa = 0.68 year-1

Target conservation reference points

The target reference point used for the simulations was Fmax = 0.33, as given by WGSSDS 2005 (ICES 2006b; Table 2.3). The increase in the Fmax value in recent years may be explained by apparent changes in the exploitation pattern.

Table 2.3 Fmax Estimates

Assessment year | Fmax |

2002 | 0.28 |

2003 | 0.29 |

2004 | 0.31 |

2005 | 0.33 |

Average | 0.30±0.04 |

LTMS options examined

The fishery closure in Quarter 1 is assumed to have resulted in an approximately 10% reduction in F on cod in 2005, based on the analysis by Ifremer (Biseau, Working Document 1).

Given the uncertainties in the assessment of this stock, it was decided not to examine HCRs that rely upon having an accurate assessment each year. Hence, the cod recovery plan objective for other European cod stocks of achieving a 30% year-on-year SSB increase with +/- 15% constraint on annual TAC changes was not examined. The options examined were:

A: 10% annual reduction in F until Fmax of 0.33 is reached, then F=0.33 thereafter

B: F reduced in equal annual increments to reach Fmax by 2015.

C: Continuation of status-quo F (for purposes of comparison)

D: Constant catch from 2005 onwards (options examined: 5,000t, 6,000t…….9,000t).

Five sensitivity tests were carried out for selected LTMS options using the following scenarios:

S1 Future recruitment lower than expected from historical estimates (e.g. due to climate change)

S2 Fishing mortality in 2003 and 2004 did not reduce in response to the decline in fishing effort – i.e. population numbers are lower in 2005, and Fsq correspondingly higher.

S3. Combination of above

S4 +15% bias assumed in estimates of population numbers

S5 No reduction in F due to Quarter 1 fishery closure.

Runs are identified by their codes: e.g. run A_S1 is option A with sensitivity test S1.

An additional run was carried out following implementation of sensitivity test S3, to examine the mitigating effect of a more rapid reduction in F towards Fmax than given by scenario A_S3. This is referred to as E_S3.

Projections

Simulations were carried out using the CS5 model. Several of the simulations were also carried out using the software package F-PRESS for comparison (Codling and Kelly, in press), as this makes a number of different assumptions to CS5 in regard to how uncertainty is modelled.

Settings

Assumptions in the CS5 and supporting F-PRESS simulations are summarised in Table 2.4.

Inputs to the management strategy simulations using CS5 are given below (alternative values used for sensitivity tests are given in italics).

- Population numbers at ages 2 – 7+ in 2005 taken from the short-term forecast to 2005 using effort-predicted F in 2003 and 2004 ( reduced numbers from prediction using F sq in 2003 and 2004 )

- CV of population numbers representative of recent ICES XSA results, rounded up to allow for probable under-estimation of error variance in XSA.

- Recruits at age 1 from 2006 onwards calculated from “hockey stick” SRR with SSB breakpoint 13,300t and recruitment asymptote 4,600m fish, with log SE 0.79. The breakpoint was defined from inspection of the LOESS smoother fitted to historic S-R data by WGSSDS (ICES 2006). Log-normal random recruit values were generated from the SRR after adjustment of the SRR by exp(-σ2/2) where σ = 0.79. Recruits at age 1 in 2005 = long term GM recruitment. ( Recruits from SRR fitted after excluding historic strong year classes >6,000m fish; SSB breakpoint 12,000t; R asymptote 3,000m, log SE 0.56. Recruits in 2005 = GM of reduced data set )

- Catch and stock weights at age = 1990-2004 average over a period of stable weights, allowing a better estimate of variance for these values than a 3 year recent average.

- Exploitation pattern = mean F-at-age for 2000-2002 from SGMOS XSA run to 2002, scaled to F2-5 in 2004 (=Fsq for simulations) rather than to 1.0.

- Natural mortality and maturity values as given by WGSSDS (ICES 2006b).

- Reduction in fishing mortality of ~10% from 2005 onwards which is expected due to the fishery closure in first quarter, based on analysis of effort displacement and spatial LPUE, and direct observations of effect of closure.

The options and settings for the CS5 simulations are summarised in Table 2.5.

The F-PRESS runs used the same inputs. This model differed from CS5 in assuming normal error distributions, and in applying random variability to fishing mortality rather than population numbers after the first year of the simulation. Population numbers in year 1 are drawn from the same probability distributions in both models.

Table 2.4. Simulation assumptions for Celtic Sea cod, as in conceptual framework given by ICES SGMAS report (ICES CM 2005/ACFM:09).

stock wts | 1990-2004 mean; fixed | SD of observations | normal | assessment data | treated as exact in CS5; error incl. In F-PRESS |

M | Fixed M = 0.2 | CV = 0.1 (assumed) | normal | assumed | treated as exact in CS5; error incl. In F-PRESS |

S-R model | Ockham | Log SD = 0.73 | lognormal | XSA | Normal error in F-PRESS |

Dynamics | Standard age-structured |

Fishery model | catch wts | 1990-2004 mean; fixed | SD of observations | normal | Assessment data | treated as exact in CS5; error incl. In F-PRESS |

selectivity | 2000-2002 mean; fixed | XSA | treated as exact in CS5 and F-PRESS |

spatial structure | not modelled |

Observation model | landings | Treated as exact |

discards | not modelled | Not included |

abundance | Errors subsumed in assessment model |

Assessment model | population nos. | Random error applied to CS5 operating model as proxy for assessment error | 0 or 15% | Typical CV's from XSA | normal | XSA | CVs applied annually in CS5; 1st yr in F-PRESS. 15% bias applied as sensitivity test |

F | Target F specified annually |

Implementation error | non-compliance | not explicitly modelled |

closure effectiveness | Variable F | 0 or 10% redn in F | varied as sensitivity test |

discarding | Not modelled |

F | Random error | CV = 0.15 | normal | Residuals from effort-F relationships | CV applied annually in F-PRESS only. Assessment error in CS5 generates implementation error in F. |

Table 2.5. Celtic Sea cod: summary table for a number of different management strategy simulations

A-S1 | Reduced Ockham 12000/3000/0.56 | as in A | 0.9Fsq | F -10% p.a. to Fmax | Fmax | CV on population nos. | sensitivity |

A-S2 | Ockham as in option A | Pessimistic forecast with F in 2003/04 = 2000-02 mean (Fsq= 0.85) | 0.9Fsq | F -10% p.a. to Fmax | Fmax | CV on population nos. | sensitivity |

A-S3 | Reduced Ockham as A_S1 | Pessimistic forecast as in A-S2 | 0.9Fsq | F -10% p.a. to Fmax | Fmax | CV on population nos. | sensitivity |

A-S4 | Ockham as in option A | as in A | 0.9Fsq | F -10% p.a. to Fmax | Fmax | CV on population nos. with +15% bias | sensitivity |

A-S5 | Ockham as in option A | as in A | 1.0 Fsq | F -10% p.a. to Fmax | Fmax | CV on population nos. | sensitivity |

B | Ockham as in option A | as in A | 0.9Fsq | F reduced to Fmax in equal steps until 2015 | Fmax | CV on population nos. | HCR |

C | Ockham as in option A | as in A | 0.9Fsq | 0.9*Fsq | 0.9Fsq | CV on population nos. | HCR |

D | Ockham as in option A | as in A | 0.9Fsq | Constant catch (5kt, 6kt…9kt) | Const TAC | CV on population nos. | HCR |

E-S3 | Reduced Ockham as A_S1 | Pessimistic forecast as in A-S2 | 0.9Fsq | F -30% every year until Fmax | Fmax | CV on population nos. | sensitivity |

1 Ockham 13300t/4600/0.79 = SSB breakpoint 13,300 t ; recruitment asymptote 4600 m fish ; residual error log SD = 0.79

Results

Results of the simulation options A, C and D and sensitivity tests A_S1 to A_S4 listed in Table 2.4 are given in detail in Annex 1 Figures 1-9. Summary plots comparing the trends in mean landings, median SSB and probability of SSB<Blim are given in Annex 1 Figs 10-11, including results of options B and A_S5 (note that the “probability of recovery by year” plot in the CS5 output is probability of SSB>Blim for two successive years whilst the “probability SSB > Blim” plot in Annex 1 Figs 10-11 is the probability in any one year).

Strategy of maintaining F sq (Run C)

Maintaining Fsq at the 2004 value of 0.61 adjusted for the 10% reduction due to the fishery closure (F=0.55) results in landings increasing progressively from around 6,000t in 2005 to 10,000t with a very high probability of SSB > Blim (run C: Annex 1 Fig.1). If the Q1 closure is assumed to have no significant effect on F (i.e. Fsq =0.61), the landings increase to 8,000 t in the medium term, but with a probability of SSB > Blim declining to 80% (run C_S5: Annex 1 Fig 10).

For scenarios where the stock size in 2005 is derived from the “pessimistic” forecast, or where future average recruitment is lower than observed historically (F-PRESS run C_S1: Annex 1 Fig 15), the Fsq strategy results in static or declining SSB and landings over time. Hence, given the uncertainty in the state of the stock and future recruitment patterns,, an Fsq strategy may be considered inappropriate for this stock at the present time.

Constant catch strategies (Run D)

A constant catch strategy leads to an increase in the median SSB if the amount of allowable catches does not excess 8,000 t. However, even with lower constant-catch strategies down to 6,000 t the probability of SSB falling below Blim can be high (Annex 1 Figs 4 and 10) since in some occurrences with low SSB, a very high F is required (by the model) to achieve the fixed catches, leading to a further depletion. Even with a very high F, the catches would sometimes not reach the TAC due to stock collapse. This explains why, in Annex 1 Fig. 10, the mean landings resulting from the constant TAC scenario of 7,000t could be much lower than the fixed TAC.

Reducing F progressively to F max (Runs A & B and sensitivity tests)

Reducing F by 10% each year until Fmax of 0.33 is reached, then F=0.33 thereafter, results in average landings increasing gradually until 2010 when Fmax is reached (Annex 1 Figs 2&10). Maintaining F at Fmax in subsequent years would lead to a further increase in landings, which are expected to stabilise in the late 2010’s at around 11,600 t. The median SSB increases to over 30,000t, with very high probability of SSB > Blim.

A smaller rate of reduction in F by equal annual increments to reach Fmax in 2015, would obviously lead to the same long-term result, while the short-term landings would be slightly higher (Annex 1 Fig. 10). However, the Group felt that the more rapidly the fishing mortality is reduced, the safer the stock will be, and decided that the scenario assuming a 10% reduction in F each year until Fmax shoud be considered as the most appropriate scenario, and is called the ‘base case’ in the following. Table 2.6 and Figure 2.2 show the input parameters and the results of this scenario, respectively.

Table 2.6. Input values for base-case CS5 run on Celtic Sea cod. Expl(F) is the status quo F , not scaled to Fbar = 1.0, hence F-multipliers are applied to give 10% reduction in F to Fmax (=0.33). “Box” refers to Q1 cod closure imposed since 2005.

Starting year, Last year, first age, last age

2005, 2025, 1, 7

N, se log(N hat), Bias(N hat), M, Mat, Expl(F), WEST, WECA

3300 0.80 1.0 0.2 0 0.147 0.584 0.842

1868 0.40 1.0 0.2 0.39 0.559 1.469 2.058

598 0.25 1.0 0.2 0.87 0.645 4.337 4.622

221 0.20 1.0 0.2 0.93 0.620 6.885 7.169

416 0.20 1.0 0.2 1 0.616 9.068 9.421

106 0.20 1.0 0.2 1 0.540 10.956 11.245

20 0.20 1.0 0.2 1 0.540 13.109 13.455

SRR parameters (if the last no. is -1 then use Ockham, otherwise Shepherd/Ricker)

4630 13300 0.0 0.0 0.729 -1

HCR % change (up, down), Fpa, SSBincr%

15,15, 0.68, -1000

Spawning Time as fraction of year

0.0

Catch in StartingYear-1

6450

Catch in the starting year, or (if negative) F (multiplier) constraint (F sq = 0.61)

-0.9

Ages for calculating reference F

2 5

Reference Biomass to calculate probabilities

6300

SSB in StartingYear-1

11000

Method For each year after starting year Rule, Target (1 - apply harvest rule, 2 - fixed F, 3 - Fixed TAC)

2 0.90

2 0.81

2 0.73

2 0.66

2 0.59

2 0.53

2 0.53

2 0.53

2 0.53

2 0.53

2 0.53

2 0.53

2 0.53

2 0.53

2 0.53

2 0.53

2 0.53

2 0.53

2 0.53

2 0.53

2 0.53

COMMENTS

Blim = 6300; Bpa = 8800; Flim = 0.90, Fpa = 0.68

RUN id : cod7fg_run2

Stock : VIIe-k cod

Starting Point : Forecasted populations in 2005 from retrospective XSA with 2002 as last data year

Constraint : Status quo F -10% (Box) from 2005 - 10% reduction each year to Fmax.

[pic]

Figure 2.2. Celtic Sea cod: CS5 Run A (see text for explanation of run combinations)

Sensitivity analysis for base case (Runs A_S1 to A_S5)

The results of the sensitivity analyses for the base case scenario (F reducing to Fmax by 10% per year) are compared in Annex 1 Fig. 11.

For the “pessimistic” forecast for 2005 starting populations (Fsq = 0.85 compared with 0.61 for “base case”), landings remain stable for several years until the F is sufficiently low to allow a more rapid increase in stock size (Run A_S2; Annex 1 Figs 5&11). Median SSB remains below Bpa until 2010, and probability of being above Blim for two consecutive years is 60-70% initially but rises to over 90% after about 7 years as F is reduced.

A more pessimistic regime for future recruitment (Run A_S1; Annex 1 Figs 6&11) mainly impacts the level of SSB and landings attained. Landings remain low until F reaches Fmax, then begin to increase. Probability of SSB > Blim remains high.

A combination of smaller initial stock size in 2005 and reduced future recruitment results in declining landings for the first 5 years and a large risk of SSB < Blim (Run A_S3; Annex 1 Figs 7&11). Median SSB remains below Bpa until 2013 and landings do not start to recover until 2014. In this case, a stronger reduction in F (by 30% each year) would decrease the risk in the short term, and would bring SSB above Bpa in 2008 (Run E_S3; Annex 1, Fig. 8&11).

Including a +15% over-estimate of stock size estimates each year in the base-case model results in a higher F than intended. This causes a small reduction in long-term landings compared with the equivalent run with un-biased stock estimates, but a larger reduction in median SSB (Run A_S4; Annex 1 Figs 9&11). However, probability of SSB > Blim remains high.

Comments

The simulations are carried out within the Precautionary Approach framework by evaluating SSB and F in relation to PA reference points proposed by ICES (ICES, 2006b).

There is currently no accepted assessment for Celtic Sea cod due to recent deterioration in data quality, and an ad-hoc method has been adopted by SGMOS to infer starting populations and status quo F for the simulations. The simulation results are very sensitive to assumptions regarding the starting populations in 2005 and the recent level of F associated with this.

The strategy of a 10% reduction in F to Fmax was robust to assumptions regarding future recruitment, which affected mainly the landings and SSB achieved in the medium to long term.

A 15% variation in TAC constraint could not be explored together with a progressive reduction in F when using the CS5 software. Examination of the simulation results for the years where the F reduction is applied shows that the proportion of occurrences for which the absolute variation from one year to the next is greater than 15% is around 61%. This is similar to the historical year-to-year variations observed in the past landings for which 67% were above 15%.

An analysis carried out by Ifremer showed that in 2005, the closure of three ICES rectangles during Quarter 1 resulted in French gadoid trawlers switching from cod fishing to fishing for benthic species such as anglerfish, megrim and rays, where cod by-catch was low (Biseau, Working Document 1). A 10% reduction in F due to this measure was included in the simulations. If the measure were to result in a smaller reduction in F, this would effectively delay the attainment of Fmax by up to 1 year under a strategy of 10% annual reduction in F.

BAY OF BISCAY SOLE

The fishery

The French fleet is the major participant in the Bay of Biscay sole fishery with landings of about 90% of the total official international landings. The remaining part is usually landed by the Belgian beam trawl fleet.

The French fishery is mainly a fixed net sole fishery. This fishery developed in the eighties expanded in the nineties and now accounts for 65-75% of the French landings. About half of the catch is taken in the first quarter when this fishery operates on the spawning grounds.

There is also a French mixed demersal fishery (sole, cuttlefish, squid, hake, pout, whiting, etc.) by otter trawlers. A major part of this fleet comprises coastal boats of less than 12 m. Although sole is taken throughout the year by trawlers, sole catches of the coastal trawlers are less important in winter.

The Belgian beam trawl fishery is directed to sole, with an important bycatch of anglerfish. This fishery operates generally from June to August.

Table 3.1: The percentage of the landings for the different fleets. Numbers are calculated from the average landings over the period 2002-04.

French fixed net fleet | 63% |

French otter trawlers | 30% |

Belgian beam trawlers | 7% |

Landings have increased continuously since the beginning of the 1980s, until a maximum was reached in 1994 (7400 t). They decreased afterwards to about 4000 t recently. Discards estimates are available for most of the fleets and are generally low (Table 3.2).

The assessment

The ICES Working Group on the Assessment of Southern Shelf Demersal Stocks (WGSSDS) caries out the assessment of Bay of Biscay sole and currently uses XSA to assess the stock (ICES 2006b). The catch at age matrix is mainly composed of the French fixed net fleet, and the assessment is tuned with three commercial trawler fleets and two surveys. The surveys were discontinued in 2002. The lack of survey data is a deficiency in the assessment, especially for estimating incoming recruitment.

The assessment summary is presented in Figure 3.1.

Retrospective analysis shows that F is underestimated in the terminal year (on average 20%) and therefore SSB is overestimated.

The Management

Management of Bay of Biscay sole is by TAC and technical measures. The 2004 TAC was set at 3600 t. The 2005 TAC is set at 4140 t. The minimum landing size is 24 cm and the minimum mesh size is 70 mm for trawls and 100 mm for fixed nets, when directed to sole. Since 2002, the minimum mesh size was increased to 100 mm for trawlers operating in those areas of the Bay of Biscay that fall under the hake recovery plan.

Figure 3.1 : Bay of Biscay sole summary plots for the XSA assessment used to generate starting values for management strategy simulations (ICES, 2006b).

Table 3.2: Bay of Biscay sole (Division VIIIa,b). Internationnal landings and catches used by the Working Group (in tonnes).

Long term management strategies

Limit and precautionary reference points

There is no biomass limit reference point set for Bay of Biscay sole. The F limit reference point and the precautionary reference points for this stock are indicated below. Flim = 0.50 year-1

Fpa = 0.36 year-1

Bpa = 13000 t

Bpa is based on the historical development of the stock and was set equal to Bloss (= 13000 t) as estimated in the 2001 WGSSDS. However, successive assessments have revised this estimate and the estimate in the most recent assessment is 11200 t. Given this uncertainty, the value of Bpa has been kept at 13000 t and is used as a trigger value in some long term management scenarios (see section 3.5).

In 2001 Flim was set at Floss, based on the historical development of the stock. Floss is statistically well determined but not sound biologically since there is no stock-recruitment relationship. Consequently the current basis to set Flim and Fpa is weak. Furthermore the estimates of Floss vary between years. Using the same rational as in 2001, Flim can now be estimated at 0.59, and Fpa at 0.42. Therefore Fpa was not considered as a reference point for setting possible HCR.

Target conservation reference points

In 2005 the Fmax was estimated to be 0.21 (Table 3.3) and this value was used as a target conservation reference point in the simulations. Fmax is well defined for this stock, with an acceptable variability between years.

Table 3.3: Estimated Fmax for Bay of Biscay Sole.

Assessment year | Fmax |

2001 | 0.18 |

2002 | 0.19 |

2003 | 0.20 |

2004 | 0.24 |

2005 | 0.21 |

Average | 0.20 ± 0.02 |

The simulations for Bay of Biscay sole did focus on F based scenarios, reducing F towards the target conservation reference point of 0.21. Section 3.5 outlines the different F-based scenarios selected for this stock and explains in more detail why these scenarios were chosen.

Projections

The programs that were used for the simulation are CS5 and CP.

Settings

The simulation assumptions are summarized in Table 3.4.

Table 3.4: Simulation assumptions for Bay of Biscay Sole.

Model | Parameter | model | bias | uncertainty | error dist | source | Comments |

Biological | Mo | sampling |

Wbars | sampling |

M | assumption |

R | Ockham | 0.3 | historical S-R |

Fishery | Wbarc | sampling |

selectivity | Not considered |

spatial structure | Not considered |

Observation | C | sampling |

Discards | Low impact |

abundance | Not available |

Assessment | N | XSA | +25% | 0.15 | lognormal | WGSSDS 05 |

F | XSA | -20% | WGSSDS 05 | bias estimated from retrospective analysis |

Implementation Error | F multiplier | assumption |

General settings

All simulations start in 2006. There is one TAC based scenario, the others are F based. Natural mortality and maturity were considered constant. Population numbers in the beginning of 2006 and their log standard errors were taken from the assessment and predictions carried out by the 2005 WGSSDS (ICES 2006b). Similarly the catch estimate for 2005 was taken from the short term prediction. The exploitation pattern was the average over the period 2000-05. Catch and stock weights were the average over the period 2002-04.

There were no scenarios carried out with a 15% constraint on annual TAC changes. The results of such scenarios would not have differed from the ones carried out since the yearly TAC change for all simulations was less than 15%.

The stock-recruitment curve is not well defined for this stock. Therefore the Ockham model was used for estimating recruitment. The breakpoint for the curve was set at (11200;23602) corresponding to the lowest observed biomass in the converged part of the assessment and the GM recruitment calculated over the period 1993-2003.

Scenarios

The settings for the different scenarios are briefly described below. Scenarios 1-6 are HCR scenarios, while scenarios 7-9 look at the sensitivity to a possible bias in the estimates of the population numbers and the robustness of the HCR to implementation errors. The different scenarios settings are summarized in Table 3.5.

Table 3.5: Settings for the different scenarios used for Bay of Biscay Sole.

Scenario | S/R | Constraint TAC change | F 2006 | F 2007 onwards | Target | Error | Type |

1 | Ockham | / | Fsq | Fsq | Fsq | / | HCR |

2 | Ockham | / | TAC05 | TAC05 | Constant TAC | / | HCR |

3 | Ockham | / | 0.9Fsq | F -10% every year | Fmax | / | HCR |

4 | Ockham | / | 0.9Fsq | F -10% every 3 years | Fmax | / | HCR |

5 | Ockham | / | 0.9Fsq | If SSB < Bpa: F -10% every year else if SSB > Bpa: F -3% every year | Fmax | / | HCR |

6 | Ockham | / | 0.9Fsq | If SSB < Bpa: F -10% every year else if SSB > Bpa: F -10% every 3 years | Fmax | / | HCR |

7 | Ockham | / | 0.9Fsq | If SSB < Bpa: F -10% every year else if SSB > Bpa: F -3% every year | Fmax | 25% bias in N | Sensitivity |

8 | Ockham | / | 0.9Fsq | F -10% every year | Fmax | 5% implementation error | Robustness |

9 | Ockham | / | 0.9Fsq | If SSB < Bpa: F -10% every year else if SSB > Bpa: F -3% every year | Fmax | 5% implementation error | Robustness |

The inputs and the output figures for scenarios 3 are presented in this section, those for the other scenarios can be found in the Annex |

Scenario 1 assumes a status quo fishing mortality from 2006 onwards. Fsq = 0.52 is the average over the period 2000-04 (same as in WGSSDS 2005). Scenario 2 simulates what happens when landings are kept at a constant level that is the same as the TAC of 2005. Scenarios 3-6 simulate different HCRs. Fishing mortality in 2006 is set at 0.9 x Fsq for all these scenarios. This is an arbitrary choice but since the TAC for 2006 will probably be set at a level corresponding to a fishing mortality equal to or lower than Fpa (= 0.36), F in 2006 will be lower than Fsq (= 0.52). The simulation settings are for:

• Scenario 3 a 10% reduction in F every year until the target reference point Fmax (= 0.21) is reached;

• Scenario 4 a 10% reduction in F every three years until Fmax is reached;

• Scenario 5 a 10% reduction in F every year if SSB is below Bpa, and a 3% reduction in F every year if SSB is above Bpa. F is reduced until Fmax is reached (input and results in Table 3.6 and Figure 3.2), and;

• Scenario 6 a 10% reduction in F every year if SSB is below Bpa, and a 10% reduction in F every three years if SSB is above Bpa. F is reduced until Fmax is reached.

Note that the CS5 program has no predefined options for scenarios 5 and 6. Hence the different F values corresponding to the preset conditions were calculated manually. Scenario 7 looks at the sensitivity to the estimates of the population numbers. After all, given the underestimation of F in the assessment of Bay of Biscay sole, the estimates of the population numbers in the beginning of 2006 might be biased. The underestimation of F in the final year is on average 20%. Taking into account this underestimation, the population numbers might be overestimated on average by 25%. The 25% bias is simulated in this scenario 7. The HCRs were the same as scenario 5. Scenarios 8 and 9 are similar to scenarios 3 and 5 respectively, but with an assumed implementation error of 5%.

Results

The scenario input data and output results that are not presented under this section can be found in Annex 2.

Fishing at status quo fishing mortality (Scenario 1) would bring SSB further down into unknown population dynamics. Scenario 2 suggests that the stock can sustain landings at a level that is similar to the 2005 TAC. As catch rates increase over time, effort should decrease accordingly in order to keep the landings at the same level. Scenarios 3-6 simulate different HCR with Fmax as long term target. Scenario 5 (Table 3.6 and Figure 3.2) might be the best option that finds a balance between biological and socio-economic priorities under the condition that the F reductions corresponding to the HCR are actually realised. If a yearly reduction of 10% in F is realised, the stock will be above Bpa within 2-3 years from now. From then onwards less severe yearly reductions bring F to the target in ~20 years. Equilibrium SSB is around 30000 t. Note that the highest SSB values observed so far are around 20000 t. Although this scenario results in short term losses in yield compared to fishing at status quo, estimated yields would remain above the TAC05 of 4140 t. Long term yields are estimated to be around 5000 t. If an implementation error of 5% is assumed (Scenario 9), then there is a low probability that F will reach the Fmax target, and that the stock will increase into known population dynamics.

With a yearly 10% reduction, F reaches Fmax by 2015 (Scenario 3). This scenario is in agreement with the commitments made on the World Summit of Johannesburg. Applying an implementation error of 5% (Scenario 8) fishing mortality is unlikely to reach the Fmax target.

The sensitivity of the HCR to a bias in the population numbers is simulated in Scenario 7. A bias in population numbers of 25% corresponding to an underestimation in F of on average 20% results in a delay in achieving the targets of ~10 years.

Comments

Although the current status of Bay of Biscay sole is not in such a way that the stock is at a high risk of

collapsing, current SSB is estimated to be at a lower level and current fishing mortality is too high. Therefore measures to reduce fishing mortality and increase biomass in the short term are required. These should be complemented with long term management goals. Such a long term target point for this stock is Fmax. To get to Fmax different HCRs can be developed, hence the different scenarios to get to Fmax that are presented here are not exclusive. It is clear that the more severe the reductions in F are, the quicker Fmax is reached and vice versa. For Bay of Biscay sole stringent measures need to be taken in the short term to bring the stock back as quickly as possible into known population dynamics while in the longer term gradual but less severe F reductions towards Fmax might be more acceptable. Scenario 5 (10% F reduction if SSB < Bpa, 3% F reduction if SSB > Bpa, target Fmax) might be a possible HCR that fits to these conditions. It is obvious that scenario 5 considers that the F reductions are actually realised. Simulating an implementation error of 5% on this scenario shows that the Fmax target may not be reached. A re-evaluation of the HCR is therefore necessary within 3 years. If the presupposed goals are not met, new HCRs should be developed including stronger reductions in F.

Beside implementation errors, the HCR is also sensitive to the bias in population number estimates. A bias in population numbers of 25% results in a delay in achieving the targets of ~10 years.

The scenarios consider that fishing mortality can be reduced with according effort reductions. In the case of Bay of Biscay sole, the fixed net fleet is the major fishery. Conversely to the trawler fleets, regulating fishing mortality by direct effort limitations (e.g. by limiting the number of fishing days), is not as straightforward for the fixed net fleet. Other possibilities to regulate effort are regulating the number of vessels, adjusting mesh sizes, temporal and/or spatial closures, etc..

Table 3.6. Input to scenario 5 ( F06 = 0.9 Fsq; If SSB < Bpa: F -10% every year, else if SSB > Bpa: F -10% every year; Target = Fmax). Note that the CS5 program has no predefined options for scenarios 5 and 6. Hence the different F values corresponding to the preset conditions were calculated manually.

Starting year, Last year, first age, last age

2006, 2030, 1, 7

N, se log(N hat), Bias(N hat), M, Mat, Expl, WEST, WECA

23602 0.18 1.0 0.1 0.32 0.468 0.179 0.179

17316 0.18 1.0 0.1 0.83 0.957 0.22 0.22

9642 0.14 1.0 0.1 0.97 1.259 0.286 0.286

5674 0.13 1.0 0.1 1 1.191 0.356 0.356

3062 0.09 1.0 0.1 1 1.125 0.479 0.479

1004 0.09 1.0 0.1 1 0.995 0.629 0.629

1276 0.09 1.0 0.1 1 0.995 0.712 0.712

SRR parameters (if the last no. is -1 then use Ockham, otherwise Shepherd/Ricker)

23602 11200 0.0 0.0 0.3 -1

HCR % change (up, down), Fpa, SSBincr%

15, 15, .36, -1000

Spawning Time as fraction of year

0.0

Catch in StartingYear-1

4722

Catch in the starting year, or (if negative) F constraint (F pa in 2006 = 0.36)

-0.468

Ages for calculating reference F

1 5

Reference Biomass to calculate probabilities

13000

SSB in StartingYear-1

11610

Method For each year after starting year Rule, Target (1 - apply harvest rule, 2 - fixed F, 3 - Fixed TAC)

2 1. 2006

2 0.421

2 0.409

2 0.396

2 0.384

2 0.373

2 0.362

2 0.351

2 0.340

2 0.330

2 0.320

2 0.311

2 0.301

2 0.292

2 0.283

2 0.275

2 0.267

2 0.259

2 0.251

2 0.243

2 0.236

2 0.229

2 0.222

2 0.216

2 0.21

COMMENTS

RUN id : sole BB run 5 : 10% F decrease if SSB<Bpa else -3% to Fmax

Stock : Bay of Biscay sole

Starting Point : N in 2006 = SSDSWG 05

Constraint : Fixed F

[pic]

Figure 3.2. Scenario 5 results ( F06 = 0.9 Fsq; If SSB < Bpa: F -10% every year, else if SSB > Bpa: F -10% every year; Target = Fmax).

Iberian Anglerfish

The fishery

In the Atlantic Iberian Peninsula two anglerfish species are caught by Spanish and Portuguese fleets, the white anglerfish (Lophius piscatorius) and the black anglerfish (L. budegassa). The proportion of both species in the 2004 landings is shown in Table 4.1 by country. White anglerfish represented 77% of the total landings, with Spain landing 70%. In the Portuguese landings both species were equally present.

Table 4.1. Landings of each Iberian Anglerfish species by country in 2004.

The landings of anglerfish Stock (combined species) estimated by the WGHMM (ICES 2006a) (Table 4.2) show total landings of 4000 t in 2004, which are 25% higher than the landings in 2003. Landings show a decreasing trend since the mid eighties to recent years. Table 4.3 shows the proportion of anglerfish landings from fleet and country in 2004. Both fleets contributed approximately with the same landings (trawl fleet 51 %, and the static gears 49%). The importance of the anglerfish landings in the total fleet landings are different (Table 4.4). Anglerfish are by-catch species mainly for the trawl fleets being only target species for static gears (gillnets in Spain and for a component of the trammel nets in Portugal). Annex 3 shows a more detailed description of the fleets.

Table 4.2 Iberian Anglerfish landings (t) by country, ICES Division and fleet 1978-2004 as determined by the WGHMM.

[pic]

Table 4.3. Proportion of the Iberian Anglerfish landings by fleet in 2004

Table 4.4. Proportions of total landings representing Iberian Anglerfish for each fleet in 2004

Both anglerfish species are caught by Spanish bottom trawlers and static gears fleet in Div. VIIIc. In Div. IXa anglerfish are captured by the Spanish and Portuguese bottom trawlers and by the Portuguese static gears fleet. The captures do not present any clear seasonality but they show a overall decreasing trend along the year in Div. IXa. In Div. VIIIc a similar trend between the two fleets is observed during the first three quarters, with higher yields during the second quarter.

Pérez et al. (1996) showed that the Spanish discards rates of anglerfish in the trawl fleet were low (2% in weigth of the total anglerfish caught in Div. VIIIc, and lower than 1% in Subdiv. IXa-north). However, the discard rate of anglerfish in the gillnet fleet in Div.VIIIc was high: 29% in weight (31% in L.piscatorius and 18 % in L.budegassa). Anglerfish discarded were large individuals, basically due to fish in poor condition when drawing up the nets (Pérez et al.,1996).

Mixed fisheries

Anglerfish are caught in a mixed fishery with Hake, Megrins, Norway Lobster and other species. The proposal of Recovery Plans of Southern Hake and Iberian Norway lobster stocks established by STECF/SGMOS (2004) is expected to have impact on strategies for Anglerfish. The referred RP had the following elements:

• An overall effort reduction scheme applied to all vessels which land hake and Norway lobster in these areas. This should achieve an annual reduction in effort of 10% relative to the previous year.

• The closure of selected Norway lobster fishing grounds to all fishing.

The annual reduction in effort of 10% has a direct implication in the present anglerfish long term management, because the three fleets that catch hake and Norway lobster (Spanish trawl VIIIc-IXa-North, Portuguese trawl and Portuguese artisanal) also catch anglerfish. The trawl fleets catch around 50% of the Iberian anglerfish. They target a wide range of species and the anglerfish catches are very low, being mainly a by-catch.

The interactions between Iberian fisheries were analysed in the WGHMM (ICES, 2006a) and were considered high between Iberian Anglerfish and the fleets included in the Iberian Hake and Norway lobster recovery plan.

The assessment

The assessment of the Iberian Anglerfish is carried out in the WGHMM and has been based since 1998 on a non-equilibrium production model, ASPIC (Prager, 1994 and Prager, 2004) with combined species. Two commercial fleets are used in the assessment (anglerfish as by-catch), the Spanish A Coruna trawl fleet and the Portuguese trawl fleet. No survey data are used in the assessment due to the low anglerfish catches of the surveys carried out in the Iberian coast.

Assessment results (Figure 4.1) show that fishing mortality has been over FMSY along the time series, reaching lower values only in 2001 and 2002. The biomass shows a decreasing trend since the beginning of the time series being relatively stable at low levels through the last 10-15 years. During the last 5 years the biomass is estimated to be around 50% of BMSY.

Age structured models (XSA) have been used to make exploratory assessments. Results were poor due to high log catchability residuals with year effects in the tuning fleets, showing inconsistencies with model assumptions.

[pic]

Figure 4.1. Yield, F/FMSY and B/BMSY trends as estimated from WGHMM 2005.

The Management

TACs

TAC2005=1955 t is set for both species combined. For most of years the agreed TAC has been set well above the landings for the stock. Since 1998 a decrease of the TAC took place and in 2004 the landings will be higher than TAC.

Relevant gear regulations and minimum landing sizes

EU regulations:

Minimum landing size not yet fixed but there is a minimum commercial weight of 500 g.

Minimum mesh size: Trawl gears: 70 mm (55 mm for Gulf of Cadiz). 55 mm in some situations.

Static gears: 100 mm. 220 mm when anglerfish catches >30% of total catch.

National regulations:

Spain

North:

- Trawl: Min.mesh size: 55 mm. Fishing time: <18 hours per day. Min. fishing depth: 100 m.

- Static gears: <5 fishing days per week. “Rasco gillnet”: Min. mesh size: 280 mm. Max. length gear: 11 km per boat. Max. stretched net height: 3.5 m. Min. fishing depth: 50 m. Some special conditions in Vizcaya and Guipuzcoa.

South (Gulf of Cadiz):

- Trawl: Min. fishing depth: 50 m or forbidden inside the 6 miles limit from coastline.

Portugal

- Trawl: forbidden inside the 6 miles limit from coastline.

- Static gears: restrictions based on the min. distance to the coastline and the max. length of the fleets. Nets cannot be set for more than 24 hours (72 hour, if mesh size is equal or higher than 100 mm, or the fishing is carried out at depths higher than 300 metres). Trammels: minimum inner mesh size: 100 mm, with exceptions depending of the area.

Closed areas and seasons

Spain

Trawl: Six closed areas established and closure season of different duration (from 4 to 12 months depending of the closed area).

Portugal

One closed area during 3 months.

Long term management strategies

The results from the ASPIC model should be used as a relative measure of the stock status and the estimates of stock biomass and fishing mortality should be analysed relative to their respective maximum sustainable yield (MSY) values.

BMSY and FMSY points can be used as a lower boundary for the biomass and an upper boundary for F. BMSY and FMSY, defined in the context of a production model, correspond to lower exploitation levels than adopted for stocks with similar population dynamics for which PA points are based on an analytical assessment.

The actual biomass is under BMSY and the fishing mortality is above FMSY. A reduction of 57% in the actual F is necessary to reach FMSY.

PROJECTIONS

An R (R Development Core Team 2005)) function was written to make stochastic projections of biomass and yield, given the following parameters:

• annual vector of fishing mortalities (F),

• initial biomass (B1),

• r parameter

• K parameter

• CV’s for stochastic simulations

The CV’s from the ASPIC Bootstrap analysis were used for each parameter.

Simulations with the ASPICP (projection program) were also performed giving the same results (relative to the R function) for the deterministic projection and similar confidence intervals.

For the simulations, the R function was adopted due to it’s flexibility to explore different scenarios with different levels of CV’s, what is not possible with the ASPICP program.

Settings

Parameter estimates from the WGHMM 2005 (ICES 2006a) assessment were adopted for projections. The bootstrap confidence intervals of these parameters show that there are important uncertainties in some parameters. The 80% confidence intervals are indicated in Table 4.5.

In spite of these uncertainties, it is clear that actual biomass is at low levels (B/BMSY < 1) and that the actual fishing mortality is above FMSY (F/FMSY > 1) (Table 4.5).

Table 4.5. WGHMM 2005 parameter estimates for Iberian anglerfish. Deterministic estimates and bootstrap 80% confidence intervals.

Parameter | Value | -80% | +80% |

R | 0.172 | 0.09 | 0.39 | Msy/Bmsy*4 |

K (t) | 88500 | 64980 | 198200 |

B1 (2005) (t) | 19270 | 12920 | 38670 |

Fsq (2005) (y-1) | 0.2 | 0.1 | 0.3 |

BMSY (t) | 44250 | 32490 | 99110 |

MSY (t) | 3815 | 2111 | 4614 |

FMSY (year-1) | 0.08 | 0.03 | 0.14 |

B/BMSY | 0.44 | 0.36 | 0.61 |

F/FMSY | 2.33 | 1.85 | 3.83 |

The uncertainties in the parameter estimates do not have an influence in the perception of the stock status but may have an effect in the biomass and yield projections and may affect the level of fishing mortality reduction and the time that is needed for biomass to reach BMSY level.

Therefore, projections with several scenarios were performed: 1) by changing the level of fishing mortality and 2) by varying the model parameters to values that would correspond to a faster biomass growth (higher r value). Since all parameters (B1, K, F and r) are highly correlated, all parameters were changed accordingly. The objective was to analysis until what extend the biomass recovery would be faster with a higher r value.

All simulations were performed starting in 2005 with F status quo and for a period of 50 years in order to allow biomass recovery for some of the scenarios. The adopted parameters are given in Table 4.6.

Table 4.6. Simulation settings for the three r parameters.

r - parameter |

Parameter | r = 0.17 (WG2005) | r = 0.25 | r = 0.35 |

k | 88500 | 79548 | 66408 |

B1 (2005) | 19270 | 14787 | 11207 |

Cvf | 0.2 | 0.2 | 0.2 |

cvb | 0.04 | 0.04 | 0.04 |

cvr | 0.3 | 0.3 | 0.3 |

cvk | 0.03 | 0.03 | 0.03 |

MSY | 3815 | 4995 | 5781 |

FMSY | 0.086 | 0.126 | 0.174 |

BMSY | 44250 | 39774 | 33204 |

Fsq | 0.20 | 0.27 | 0.36 |

B1(2005)/BMSY | 0.44 | 0.37 | 0.34 |

Fsq/FMSY | 2.3 | 2.1 | 2.1 |

seed | 12 | 12 | 12 |

Parameters for r value of 0.17 are WGHMM estimates. For r values of 0.25 and 0.35 the parameters were obtained within the 80% bootstrap confidence interval. CV’s for the stochastic simulations were obtained from the bootstrap results of the working group.

Scenarios

For each r parameter value, 5 fishing mortality scenarios were adopted as seen in Table 4.7. Annex 3 shows the inputs and outputs for each scenario.

• Scenario 1 assumes a status quo fishing mortality from 2006 onwards.

• Scenario 2 a 10% reduction in F every year until the target reference point Fmsy is reached.

• Scenario 3 a 20% reduction in F every year until the target reference point Fmsy is reached.

• Scenario 4 a 30% reduction in F every year until the target reference point Fmsy is reached.

• Scenario 5 assumes a zero fishing mortality value (F = 0) from 2006 until B = BMSY, followed by F = FMSY.

Table 4.7. Summary table for the different scenario settings.

Scenario | S/R | Constraint TAC change | F 2006 | F 2007 onwards | Target | Error | Type |

1 | / | / | Fsq | Fsq | Fsq | / | HCR |

2 | / | / | 0.9Fsq | F -10% every year | Fmsy | / | HCR |

3 | / | / | 0.8Fsq | F -20% every year | Fmsy | / | HCR |

4 | / | / | 0.7Fsq | F -30% every year | Fmsy | / | HCR |

5 | / | / | 0 | F=0, until B=BMSY | Fmsy | / | HCR |

Results

For any r parameter, actual biomass is considered under BMSY as can be seen from the WGHMM results in Table 4.6. The projection results show that maintaining fishing mortality at the actual level (scenario 1), total biomass will progressively reduce. In the next 50 years the biomass will not invert it’s decreasing tendency (Table 4.8) and will be maintained below BMSY (Table 4.9).

Table 4.8. Number of years necessary for biomass to invert actual decreasing tendency, with a probability of 50% and 75%.

Prob. | r | Fsq | F10 | F20 | F30 | F00 |

0.17 | +50 | 5 | 3 | 3 | 2 |

50% | 0.25 | +50 | 3 | 3 | 2 | 2 |

0.35 | +50 | 3 | 3 | 2 | 2 |

0.17 | +50 | +50 | 5 | 4 | 2 |

75% | 0.25 | +50 | 7 | 4 | 3 | 2 |

0.35 | +50 | 5 | 4 | 3 | 2 |

Table 4.9. Biomass ratio to BMSY for each r parameter value and F scenario.

FR Nephrops VIIfgh | 0.0267 | 3.36 E-04 | 0.40 | 0.0899 | 0.0848 | 0.0706 |

FR Other VIIe-k | 0.0435 | 1.81 E-04 | 0.25 | 0.1221 | 0.1748 | 0.1558 |

UK Otter Trawlers VIIe-k | 3.29 E-04 | 1.69 E-04 | 0.18 | 0.0067 | 0.0126 | 0.0131 |

UK Beam Trawlers VIIe-k | -1.36 E-03 | 9.11 E-05 | 0.36 | 0.0109 | 0.0244 | 0.0236 |

Residual fleets VIIe-k , | 8.13 E-03 | 7.80 E-05 | 0.59 | 0.1472 | 0.0804 | 0.0925 |

Total F | 0.7360 | 0.6626 | 0.6091 |

- Annex 1 Table 2. Comparison of F, SSB and landings in 2002 – 2005 given by the (rejected) ICES assessment in 2005, and the values obtained from a short-term forecast to 2005 based on an XSA assessment run with 2002 as the terminal year. Two scenarios for F in 2003 and 2004 in the forecast are given. SSB and landings are in kt.

2005 WG results | SGMOS: F in 2003-2004 predicted from effort | SGMOS: F in 2003-2004 = XSA mean for 2000-2002 |

Year | F(2-5) | SSB | landings | F(2-5) | SSB | landings | F(2-5) | SSB | landings |

2002 | 0.82 | 9.7 | 8.8 | 0.741 | 10.7 | 8.8 | 0.741 | 10.7 | 8.8 |

2003 | 0.69 | 9.5 | 6.0 | 0.662 | 14.4 | 8.6 | 0.853 | 14.4 | 10.2 |

2004 | 0.59 | 6.8 | 3.4 | 0.612 | 11.4 | 6.5 | 0.853 | 9.5 | 7.0 |

2005 | 5.7 | 10.0 | 7.1 |

1 XSA estimate from run to 2002. 2 F predicted from effort. 3Mean for 2000-2002 from XSA run to 2002

[pic]

Annex 1, Figure 1. Celtic Sea cod: CS5 Run C (see text for explanation of run combinations)

[pic]

Annex 1, Figure 3 Celtic Sea cod: CS5 Run D (see text for explanation of run combinations)- Constant TAC of 5000 t

[pic]

Annex 1, Figure 4 Celtic Sea cod: CS5 Run D (see text for explanation of run combinations) Constant TAC of 7,000 t

[pic]

Annex 1, Figure 5 Celtic Sea cod: CS5 Run A_S2 (see text for explanation of run combinations)

[pic]

Annex 1, Figure 6 Celtic Sea cod: CS5 Run A_S1 (see text for explanation of run combinations)

[pic]

Annex 1, Figure 7 Celtic Sea cod: CS5 Run A_S3 (see text for explanation of run combinations)

[pic]

Annex 1, Figure 8 Celtic Sea cod: CS5 Run E_S3 (see text for explanation of run combinations)

[pic]

Annex 1, Figure 9 Celtic Sea cod: CS5 Run A_S4 (see text for explanation of run combinations)

[pic]

Annex 1 Fig. 10. Celtic sea cod: Summary of results of CS5 simulations based on starting populations in 2005 from XSA to 2002, and forecast to 2005 using F's predicted from fishing effort. (See text for explanation of run combinations)

[pic]

Annex 1. Fig. 11 Celtic Sea cod: Summary of results of CS5 simulations examining sensitivity of “base-case” model to uncertainties in starting populations, future recruitment, and assessment bias. (See text for explanation of run combinations)

[pic]

Annex 1, Figure 12- Celtic Sea cod: F-PRESS Run C - scenario with Fsq

[pic]

Annex 1, Figure 13. Celtic Sea cod: F-PRESS Run A - F reduced by 10% to F max in 2010

[pic]

Annex 1, Figure 14 Celtic Sea cod: F-PRESS Run B- Scenario with decreasing F to F max until 2015

[pic]

Annex 1, Figure 15 Celtic Sea cod: F-PRESS Run C_S1- Reduced Recruitment- scenario with Fsq

[pic]

Annex 1, Figure 16 Celtic Sea cod: F-PRESS Run B_S1 Reduced Recruitment Scenario- F reduced by 10% to F max in 2010

[pic]

Annex 1, Figure 17 Celtic Sea cod: F-PRESS Run A_S1 Reduced recruitment Scenario with decreasing F to F max until 2015

ANNEX 2 – BAY OF BISKAY SOLE

Annex 2, Table 1. Input to scenario 1 (F = Fsq).

Starting year, Last year, first age, last age

2006, 2030, 1, 7

N, se log(N hat), Bias(N hat), M, Mat, Expl, WEST, WECA

23602 0.18 1.0 0.1 0.32 0.468 0.179 0.179

17316 0.18 1.0 0.1 0.83 0.957 0.22 0.22

9642 0.14 1.0 0.1 0.97 1.259 0.286 0.286

5674 0.13 1.0 0.1 1 1.191 0.356 0.356

3062 0.09 1.0 0.1 1 1.125 0.479 0.479

1004 0.09 1.0 0.1 1 0.995 0.629 0.629

1276 0.09 1.0 0.1 1 0.995 0.712 0.712

SRR parameters (if the last no. is -1 then use Ockham, otherwise Shepherd/Ricker)

23602 11200 0.0 0.0 0.3 -1

HCR % change (up, down), Fpa, SSBincr%

15, 15, .36, -1000

Spawning Time as fraction of year

0.0

Catch in StartingYear-1

4722

Catch in the starting year, or (if negative) F constraint (F pa in 2006 = 0.36)

-0.52

Ages for calculating reference F

1 5

Reference Biomass to calculate probabilities

13000

SSB in StartingYear-1

11610

Method For each year after starting year Rule, Target (1 - apply harvest rule, 2 - fixed F, 3 - Fixed TAC)

2 1. 2006

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

2 0.52

COMMENTS

RUN id : sole BB run 1 : Fsq

Stock : Bay of Biscay sole

Starting Point : N in 2006 = SSDSWG 05

Constraint : Fixed F

Annex 2 Table 2. Input to scenario 2 (Constant TAC).

Starting year, Last year, first age, last age

2006, 2030, 1, 7

N, se log(N hat), Bias(N hat), M, Mat, Expl, WEST, WECA

23602 0.18 1.0 0.1 0.32 0.468 0.179 0.179

17316 0.18 1.0 0.1 0.83 0.957 0.22 0.22

9642 0.14 1.0 0.1 0.97 1.259 0.286 0.286

5674 0.13 1.0 0.1 1 1.191 0.356 0.356

3062 0.09 1.0 0.1 1 1.125 0.479 0.479

1004 0.09 1.0 0.1 1 0.995 0.629 0.629

1276 0.09 1.0 0.1 1 0.995 0.712 0.712

SRR parameters (if the last no. is -1 then use Ockham, otherwise Shepherd/Ricker)

23602 11200 0.0 0.0 0.3 -1

HCR % change (up, down), Fpa, SSBincr%

15, 15, .36, -1000

Spawning Time as fraction of year

0.0

Catch in StartingYear-1

4722

Catch in the starting year, or (if negative) F constraint (F pa in 2006 = 0.36)

4140

Ages for calculating reference F

1 5

Reference Biomass to calculate probabilities

13000

SSB in StartingYear-1

11610

Method For each year after starting year Rule, Target (1 - apply harvest rule, 2 - fixed F, 3 - Fixed TAC)

3 4140 2006

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

3 4140

COMMENTS

RUN id : sole BB run 2 : constant TAC

Stock : Bay of Biscay sole

Starting Point : N in 2006 = SSDSWG 05

Constraint : Constant TAC

Annex 2 Table 3. Input to scenario 3 (F06 = 0.9 Fsq; F 2007 onwards: -10% every year; Target = Fmax).

Starting year, Last year, first age, last age

2006, 2030, 1, 7

N, se log(N hat), Bias(N hat), M, Mat, Expl, WEST, WECA

23602 0.18 1.0 0.1 0.32 0.468 0.179 0.179

17316 0.18 1.0 0.1 0.83 0.957 0.22 0.22

9642 0.14 1.0 0.1 0.97 1.259 0.286 0.286

5674 0.13 1.0 0.1 1 1.191 0.356 0.356

3062 0.09 1.0 0.1 1 1.125 0.479 0.479

1004 0.09 1.0 0.1 1 0.995 0.629 0.629

1276 0.09 1.0 0.1 1 0.995 0.712 0.712

SRR parameters (if the last no. is -1 then use Ockham, otherwise Shepherd/Ricker)

23602 11200 0.0 0.0 0.3 -1

HCR % change (up, down), Fpa, SSBincr%

15, 15, .36, -1000

Spawning Time as fraction of year

0.0

Catch in StartingYear-1

4722

Catch in the starting year, or (if negative) F constraint (F pa in 2006 = 0.36)

-0.468

Ages for calculating reference F

1 5

Reference Biomass to calculate probabilities

13000

SSB in StartingYear-1

11610

Method For each year after starting year Rule, Target (1 - apply harvest rule, 2 - fixed F, 3 - Fixed TAC)

2 1. 2006

2 0.421

2 0.379

2 0.341

2 0.307

2 0.276

2 0.249

2 0.224

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

COMMENTS

RUN id : sole BB run 3 : 10% F decrease to Fmax

Stock : Bay of Biscay sole

Starting Point : N in 2006 = SSDSWG 05

Constraint : Fixed F

Annex 2 Table 4. Input to scenario 4 (F06 = 0.9 Fsq; F 2007 onwards: -10% every three years; Target = Fmax).

Starting year, Last year, first age, last age

2006, 2030, 1, 7

N, se log(N hat), Bias(N hat), M, Mat, Expl, WEST, WECA

23602 0.18 1.0 0.1 0.32 0.468 0.179 0.179

17316 0.18 1.0 0.1 0.83 0.957 0.22 0.22

9642 0.14 1.0 0.1 0.97 1.259 0.286 0.286

5674 0.13 1.0 0.1 1 1.191 0.356 0.356

3062 0.09 1.0 0.1 1 1.125 0.479 0.479

1004 0.09 1.0 0.1 1 0.995 0.629 0.629

1276 0.09 1.0 0.1 1 0.995 0.712 0.712

SRR parameters (if the last no. is -1 then use Ockham, otherwise Shepherd/Ricker)

23602 11200 0.0 0.0 0.3 -1

HCR % change (up, down), Fpa, SSBincr%

15, 15, .36, -1000

Spawning Time as fraction of year

0.0

Catch in StartingYear-1

4722

Catch in the starting year, or (if negative) F constraint (F pa in 2006 = 0.36)

-0.468

Ages for calculating reference F

1 5

Reference Biomass to calculate probabilities

13000

SSB in StartingYear-1

11610

Method For each year after starting year Rule, Target (1 - apply harvest rule, 2 - fixed F, 3 - Fixed TAC)

2 1. 2006

2 0.468

2 0.468

2 0.421

2 0.421

2 0.421

2 0.379

2 0.379

2 0.379

2 0.341

2 0.341

2 0.341

2 0.307

2 0.307

2 0.307

2 0.276

2 0.276

2 0.276

2 0.249

2 0.249

2 0.249

2 0.224

2 0.224

2 0.224

2 0.21

COMMENTS

RUN id : sole BB run 4 : 10% F decrease /3years to Fmax

Stock : Bay of Biscay sole

Starting Point : N in 2006 = SSDSWG 05

Constraint : Fixed F

Annex 2 Table 5. Input to scenario 6 (F06 = 0.9 Fsq; If SSB < Bpa: F -10% every year, else if SSB > Bpa: F -10% every three years; Target = Fmax). Note that the CS5 program has no predefined options for scenarios 5 and 6. Hence the different F values corresponding to the preset conditions were calculated manually.

Starting year, Last year, first age, last age

2006, 2030, 1, 7

N, se log(N hat), Bias(N hat), M, Mat, Expl, WEST, WECA

23602 0.18 1.0 0.1 0.32 0.468 0.179 0.179

17316 0.18 1.0 0.1 0.83 0.957 0.22 0.22

9642 0.14 1.0 0.1 0.97 1.259 0.286 0.286

5674 0.13 1.0 0.1 1 1.191 0.356 0.356

3062 0.09 1.0 0.1 1 1.125 0.479 0.479

1004 0.09 1.0 0.1 1 0.995 0.629 0.629

1276 0.09 1.0 0.1 1 0.995 0.712 0.712

SRR parameters (if the last no. is -1 then use Ockham, otherwise Shepherd/Ricker)

23602 11200 0.0 0.0 0.3 -1

HCR % change (up, down), Fpa, SSBincr%

15, 15, .36, -1000

Spawning Time as fraction of year

0.0

Catch in StartingYear-1

4722

Catch in the starting year, or (if negative) F constraint (F pa in 2006 = 0.36)

-0.468

Ages for calculating reference F

1 5

Reference Biomass to calculate probabilities

13000

SSB in StartingYear-1

11610

Method For each year after starting year Rule, Target (1 - apply harvest rule, 2 - fixed F, 3 - Fixed TAC)

2 1. 2006

2 0.421

2 0.379

2 0.341

2 0.307

2 0.307

2 0.307

2 0.276

2 0.276

2 0.276

2 0.249

2 0.249

2 0.249

2 0.224

2 0.224

2 0.224

2 0.221

2 0.221

2 0.221

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

2 0.21

COMMENTS

RUN id : sole BB run 6 : 10% F decrease if SSB<Bpa else -10%/3years to Fmax

Stock : Bay of Biscay sole

Starting Point : N in 2006 = SSDSWG 05

Constraint : Fixed F

Annex 2 Table 6. Input to scenario 7 (F06 = 0.9 Fsq; If SSB < Bpa: F -10% every year, else if SSB > Bpa: F -10% every year; Target = Fmax; 25% bias in N). Note that the CS5 program has no predefined options for scenarios 5 and 6. Hence the different F values corresponding to the preset conditions were calculated manually.

Starting year, Last year, first age, last age

2006, 2030, 1, 7

N, se log(N hat), Bias(N hat), M, Mat, Expl, WEST, WECA

23602 0.18 1.25 0.1 0.32 0.468 0.179 0.179

17316 0.18 1.25 0.1 0.83 0.957 0.22 0.22

9642 0.14 1.25 0.1 0.97 1.259 0.286 0.286

5674 0.13 1.25 0.1 1 1.191 0.356 0.356

3062 0.09 1.25 0.1 1 1.125 0.479 0.479

1004 0.09 1.25 0.1 1 0.995 0.629 0.629

1276 0.09 1.25 0.1 1 0.995 0.712 0.712

SRR parameters (if the last no. is -1 then use Ockham, otherwise Shepherd/Ricker)

23602 11200 0.0 0.0 0.3 -1

HCR % change (up, down), Fpa, SSBincr%

15, 15, .36, -1000

Spawning Time as fraction of year

0.0

Catch in StartingYear-1

4722

Catch in the starting year, or (if negative) F constraint (F pa in 2006 = 0.36)

-0.468

Ages for calculating reference F

1 5

Reference Biomass to calculate probabilities

13000

SSB in StartingYear-1

11610

Method For each year after starting year Rule, Target (1 - apply harvest rule, 2 - fixed F, 3 - Fixed TAC)

2 1. 2006

2 0.421

2 0.409

2 0.396

2 0.384

2 0.373

2 0.362

2 0.351

2 0.340

2 0.330

2 0.320

2 0.311

2 0.301

2 0.292

2 0.283

2 0.275

2 0.267

2 0.259

2 0.251

2 0.243

2 0.236

2 0.229

2 0.222

2 0.216

2 0.21

COMMENTS

RUN id : sole BB run 7 : 10% F decrease if SSB<Bpa else -3% to Fmax

Stock : Bay of Biscay sole

Starting Point : N in 2006 = SSDSWG 05 + Bias

Constraint : Fixed F

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Annex 2 Figure 1. Scenario 1 results (F = Fsq).

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Annex 2 Figure 2. Scenario 2 results (Constant TAC)

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Annex 2 Figure 3. Scenario 3 results (F06 = 0.9 Fsq; F 2007 onwards: -10% every year; Target = Fmax).

[pic]Annex 2 Figure 4. Scenario 3 results – CP program (F06 = 0.9 Fsq; F 2007 onwards: -10% every year; Target = Fmax).

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Annex 2 Figure 5. Scenario 4 results (F06 = 0.9 Fsq; F 2007 onwards: -10% every three years; Target = Fmax).

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Annex 2 Figure 6. Scenario 5 results – CP program (F06 = 0.9 Fsq; If SSB < Bpa: F -10% every year, else if SSB > Bpa: F -3% every year; Target = Fmax).

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Annex 2 Figure 7. Scenario 6 results (F06 = 0.9 Fsq; If SSB < Bpa: F -10% every year, else if SSB > Bpa: F -10% every three years; Target = Fmax). Note that the CS5 program has no predefined options for scenarios 5 and 6. Hence the different F values corresponding to the preset conditions were calculated manually.

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Annex 2 Figure 8. Scenario 7 results (F06 = 0.9 Fsq; If SSB < Bpa: F -10% every year, else if SSB > Bpa: F -10% every year; Target = Fmax; 25% bias in N). Note that the CS5 program has no predefined options for scenarios 5 and 6. Hence the different F values corresponding to the preset conditions were calculated manually.

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Annex 2 Figure 9. Scenario 8 results (F06 = 0.9 Fsq; F 2007 onwards: -10% every year; Target = Fmax; 5% implementation error).

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Annex 2 Figure A 10. Scenario 9 results (F06 = 0.9 Fsq; If SSB < Bpa: F -10% every year, else if SSB > Bpa: F -10% every year; Target = Fmax; 5% implementation error). Note that the CS5 program has no predefined options for scenarios 5 and 6. Hence the different F values corresponding to the preset conditions were calculated manually.

ANNEX 3 – IBERIAN ANGLERFISH

fleets

SPAIN

Anglerfish captures represented a low proportion (3%) of the total catch in the Spanish demersal fisheries in 2004. Different fleets are distinguished depending on the area: the North Spanish fleets (Div. VIIIc and IXa-north) that captured 98% of the anglerfish in 2004, and the Spanish fleets in the Gulf of Cadiz (Div. IXa-south) that captured 2% of the anglerfish in 2004.

North Spanish fleets (Cantabrian Sea and NW Spain)

A description of North Spanish fleets (Div. VIIIc and IXa-north) operating in the Atlantic Iberian Peninsula shelf was compiled in 2002 (STECF, 2002) updating the information of the period 1986-1993 (STECF, 1994) using the results of recent studies (Lart et al ., 2002)

Trawl fleet : Anglerfish represent 3% of landings of this fleet in 2004. It is composed of different units:

• Bottom otter trawl (OTB). Around 235 vessels. It caught 88% of the anglerfish captured by trawl in 2004. It targets a wide range of species including horse mackerel, blue whiting, mackerel, hake, anglerfish, megrims, and Nephrops. Anglerfish: 6% of landings of this fleet in 2004. Five trip types obtained in the OTB (Castro and Punzón, 2005):

- “ OTB-HM ” (VHVO): Bottom otter trawl trips targeting horse mackerel (> 70% in landings). Anglerfish: 4% of landings in 2004.

- “ OTB-M ”: Bottom otter trawl trips targeting mackerel (> 73% in landings). Anglerfish: 3% of landings in 2004.

- “ OTB-BW ”: Bottom otter trawl trips targeting blue whiting (> 40% in landings). Anglerfish: 8% of landings in 2004.

- “ OTB-demersal ”: Bottom otter trawl trips targeting anglerfish, megrims, hake, Nephrops and “other” species. Anglerfish: 40% of landings in 2004.

- “ OTB-mixed ”: Bottom otter trawl trips with mixed catch, mainly “other” species and megrims, anglerfish, hake and Nephrops . Anglerfish: 10% of landings in 2004.

• Bottom pair trawl (PTB): Around 68 pairs (136 vessels). This fleet caught 12% of the anglerfish captured by trawl in 2004. It catches mainly blue whiting (above 80%) and other pelagic species. Anglerfish: 1% of landings of this fleet in 2004. Two trip types obtained in the PTB:

- “PTB-BW”: Bottom pair trawl trips targeting blue whiting (> 87% in landings). Anglerfish: 1% of landings in 2004.

- “PTB-H”: Bottom pair trawl trips targeting mainly hake (but also pelagic species as blue whiting, mackerel and horse mackerel). Anglerfish: 5% of landings in 2004.

Static gears fleet : Around 230 vessels (40 “rasco” vessels). There are three kinds of fixed nets depending on mesh size. "Rasco" (280 mm on mesh size) is directed to anglerfish on the shelf edge and these species are around 90% of total landings by "rasco" in 2004.

Artisanal fleet : Around 8300 vessels. Anglerfish: 1% of landings in 2004.

Spanish fleets in the Gulf of Cadiz.

The Spanish fleets in the Gulf of Cadiz (Div. IXa-south) were described compiling new information available in Velasco et al . (2003).

Trawl fleet : Around 231 vessels. It targets a wide range of species including blue whiting, pink shrimp, hake, horse mackerel, cephalopods, Nephrops and wedge sole. Anglerfish: 1% of landings in 2004. .

Artisanal fleet : Around 642 vessels. Its main species are sparids (mainly red seabream), cephalopods, wedge sole, and prawn. Anglerfish lower than 0.1% of landings in 2004.

PORTUGALl

Anglerfish are caught by the Portuguese fleet in the trawl and artisanal mixed fishery. The Portuguese landings of anglerfish were 83% from the artisanal fishery and 17% from the trawl fleet, during last three years (2002-2004).

Artisanal fleet : Around 8500 vessels. There is a component of the trammelnets fleet that target anglerfish and it is the main gear with the most of the landings.

Trawl fleet : Anglerfish are a by-catch for these fleets y represent a low % of their landings. The trawl fleet comprises two components e.g., trawl fleet catching demersal fish (65 mm mesh size) and trawl fleet directed to crustaceans (55 mm mesh size). Anglerfish is more important for the trawl fleet directed to crustaceans.

DISTRIBUTION AND ABUNDANCE

SPAIN

The abundance indices of both anglerfish from the Spanish Bottom Trawl Survey that took place in October in northern Spain (Div. VIIIc and IXa-north), and in November in the Gulf of Cadiz (Subdiv. IXa-south) during last three years (2002-2004) were analysed.

In northern Spain, both anglerfish appear in the area as euribathial, occupying in a wide depth range, from 30 to 700 m (Sánchez, 1993). At the beginning of the historical series of surveys (1983-1986), the data showed a higher abundance index of L. piscatorius , located in shallower bottoms (50-300 m), and L.budegassa preferring deeper waters (75-400 m) (Sánchez, 1993). This abundance and distribution pattern has varied with the years, being the abundance of L budegassa more reduced in the last years, and L.piscatorius occupying a wider area of distribution, with higher abundance indices.

L.piscatorius specimens smaller than 25 cm show a northerly distribution (Div. VIIIc), with greater concentration in their central and western areas. The spatial distribution of the specimens larger than 25 cm is more uniform throughout all the North zone (Div. VIIIc), with scarcity of specimens in the south-western zone (Subdiv. IXa-north). This distribution, with greater indices mainly in the north (Div. VIIIc), also has been observed in the surveys during years 1991-1993 (Sanchez et al. , 1995) and 1997-1999 (Sanchez et al., 2002) although then they only occupied the Cantabrian Sea (Subdiv. VIIIc-east). The abundance of L.piscatorius in the Gulf of Cadiz (Subdiv. IXa-south) was very low.

The low recruitments of L.budegassa during the last years show a concentration of them in the north of Galicia (Subdiv. VIIIc-west) and eastern Cantabrian Sea (Subdiv. VIIIc-east). The spatial distribution of the specimens larger than 25 cm show a low abundance with higher concentrations in eastern Cantabrian Sea (Subdiv. VIIIc-east). This species shows a very clear decrease of the abundance indices during the last years (2002-2004) compared with the results of the surveys of 1991-1993 (Sanchez et al., 1995) and 1997-1999 (Sanchez et al ., 2002) where they were also more uniformly distributed throughout all the area. L. budegassa in the Gulf of Cadiz (Subdiv. IXa-south) showed low abundance values and most of the specimens were concentrated in the southern of the Gulf.

PORTUGAL

The Portuguese Bottom Trawl Survey that took place in Portuguese continental shelf (Subdiv. IXa-south) during last three years (2002-2004) showed low abundance values for both species. Most of the specimens were concentrated in the southern and south-western area of the Subdiv. IXa-south.

SIMULATIONS

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Annex 3, Figure 1. Scenario 1 results (F2006 = Fsq; F2007 onwards = Fsq; Target = Fsq; r = 0.17).

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Annex 3, Figure 2. Scenario 1 results (F2006 = Fsq; F2007 onwards = Fsq; Target = Fsq; r = 0.25).

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Annex 3, Figure 3. Scenario 1 results (F2006 = Fsq; F2007 onwards = Fsq; Target = Fsq; r = 0.35).

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Annex 3, Figure 4. Scenario 2 results (F2006 = 0.9Fsq; F2007 onwards: -10% every year; Target = Fmsy; r = 0.17).

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Annex 3, Figure 5. Scenario 2 results (F2006 = 0.9Fsq; F2007 onwards: -10% every year; Target = Fmsy; r = 0.25).

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Annex 3, Figure 6. Scenario 2 results (F2006 = 0.9Fsq; F2007 onwards: -10% every year; Target = Fmsy; r = 0.35).

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Annex 3, Figure 7. Scenario 3 results (F2006 = 0.8Fsq; F2007 onwards: -20% every year; Target = Fmsy; r = 0.17).

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Annex 3, Figure 8. Scenario 3 results (F2006 = 0.8Fsq; F2007 onwards: -20% every year; Target = Fmsy; r = 0.25).

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Annex 3, Figure 9. Scenario 3 results (F2006 = 0.8Fsq; F2007 onwards: -20% every year; Target = Fmsy; r = 0.35).

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Annex 3, Figure 10. Scenario 4 results (F2006 = 0.7Fsq; F2007 onwards: -30% every year; Target = Fmsy; r = 0.17).

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Annex 3, Figure 11. Scenario 4 results (F2006 = 0.7Fsq; F2007 onwards: -30% every year; Target = Fmsy; r = 0.25).

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Annex 3, Figure 12. Scenario 4 results (F2006 = 0.7Fsq; F2007 onwards: -30% every year; Target = Fmsy; r = 0.35).

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Annex 3, Figure 13. Scenario 5 results (F2006 = 0; F2007 onwards = 0, until B=Bmsy; Target = Fmsy; r = 0.17).

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Annex 3, Figure 14. Scenario 5 results (F2006 = 0; F2007 onwards = 0, until B=Bmsy; Target = Fmsy; r = 0.25).

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Annex 3, Figure 15. Scenario 5 results (F2006 = 0; F2007 onwards = 0, until B=Bmsy; Target = Fmsy; r = 0.35).

REFERENCES

Castro, J. & Punzón, A. 2005. Pelagic métiers of the Northern Spanish coastal bottom trawl fleet. Working Paper to the Working Group on the Assessment of Mackerel, Horse Mackerel, Sardine and Anchovy.

Lart, W. (co-ordinator). 2002. Monitoring of discarding and retention by trawl fisheries in Western Waters and the Irish Sea in relation to stock assessment and technical measures. Final Report. Contract Ref. 98/095.

Sanchez, F. 1993. Las comunidades de peces de la plataforma del Cantábrico. Publ. Espec. Ins. Esp. Oceanogr., 13, 137 pp.

Sanchez, F., de la Gandara, F. & Gancedo, R. 1995. Atlas de los peces demersales de Galicia y el Cantábrico. Otoño 1991-1993. Publ. Espec. Ins. Esp. Oceanogr., 20, 99 pp.

Sánchez, F., M. Blanco and R. Gancedo. 2002. Atlas de los peces demersales y de los invertebrados de interés comercial de Galicia y Cantábrico. Ed. Cyan, Proy. y Prod. Ed. 158 pp.

STECF. 1994. STECF Subgroup on Southern Hake Task Force. Lisbon, 10-14 October 1994. SEC (1995) 2231.

STECF. 2002. STECF Subgroup on Resource Status (SGRST) of the Scientific, Technical and Economic Committee for Fisheries (STECF) Mixed Fisheries. Brussels, 22-26 October 2002. SEC (2002) 1373.

Velasco, F.., Silva, L., and Sobrino, I. 2003. Exploring the hake Fishery in the Gulf of Cadiz: available information to perform a stock assessment. Working Document presented to the WGHMH 2003, Copenhagen 14-24 May, 2003.