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APPENDIX D

FULL ADVICE FROM THE SUB-COMMITTEE ON STOCK ASSESSMENT (SCSA) ON DEMERSAL AND PELAGIC SPECIES[1]

DEMERSAL SPECIES

FISHERIES: Hake (Merluccius merluccius) is one of the most important demersal species of commercial fisheries in the Gulf of Lions. In 2001 it was exploited by 113 French trawlers, 95 French gillnetters, 26 Spanish trawlers and 20 Spanish longliners. The catches of the trawlers are mainly composed of juveniles living on the continental shelf, while gillnetters and longliners are exploiting the adult part of the stock (spawners) living on the slope and in non trawlable areas. 80% of the landings are done by the trawlers; the total landings remained quite stable during the period 1988 (2941 tonnes) to 2001 (2693 tonnes). During the same period, the total number of trawlers decreased from 196 to 139, while the number of gillnetters increased from 20 to 95 and the longliners fleet increased from 13 to 20 boats. During some periods, discards can represent a significant part of the total European hake catch, both in weight and in number.

SOURCE OF MANAGEMENT ADVICE: Stock assessment of the French-Spanish shared stock of hake (Merluccius merluccius) in the Gulf of Lions: a comparative approach. French-Spanish Working Group (IFREMER - IEO - CMIMAICM) Length cohort analysis (LCA) and yield per recruit analysis (Y/R) were developed on a mean pseudocohort (1998-2001). The results have been compared to a previous similar analysis for the period 1988-1991. The objectives were to analyse hake dynamics in the Gulf of Lions and to compare its exploitation pattern and exploitation rate over a 10 years period.

STOCK STATUS: General status of resource: growth overexploitation. The biomass values showed a decreasing trend from 1988-91 to 1998-01 periods, but remained stable from 1998-00 to 1998-01. Current biomass is 2.37% of virgin biomass. For females, if Fcurrent is reduced by 82%, Y/Rmax would be 3.3 times higher the current value; for males, if Fcurrent is reduced by 68%, Y/Rmax would be 1.6 times higher the current value. There is a risk of recruitment overexploitation. Spawning females in the current stock have been estimated around one million of individuals, in comparison to 20 millions of individuals in the virgin stock. It seems that the spawning stock is decreasing in comparison to previous analysis (1988-91).

WORKING GROUP (WG) MANAGEMENT ADVICE AND RECOMMENDATIONS (2002): To avoid recruitment overfishing: reduce the effort of longline and gillnets in order to increase (or at least maintain) the SSB. Reduction of fishing effort could be achieved by establishing temporal closures for longline and gillnet during the period of maximum spawning, or by reducing time at sea, and/or fishing boats or/and engine power. To reduce growth overfishing: a transition analysis performed shows that the improvement of trawl selectivity is the most appropriate management measure (length at first capture fixed at 20 cm TL). Moreover, the reduction of fishing effort could be also considered: from the Y/R analysis, a reduction of about 80% of F should be necessary to reach the maximum Y/R at the current fishing pattern, but taking into consideration the short database, a reduction of 20% is recommended. This reduction is still far from the biological optima of the stock. Reduction of fishing effort could be achieved by establishing temporal closures for longline and gillnet during the period of maximum spawning, or by reducing time at sea, and/or fishing boats or/and engine power. It should be considered that the effort reduction or selectivity improvements imply losses at short term but gains at medium term.

SCSA COMMENTS AND ADVICE (2002): The SCSA endorsed the assessment and the recommendations. It emphasized that both alternatives, decreasing effort and increasing length at first capture are independent and complementary management measures to reach the objectives.

SCSA COMMENTS AND ADVICE (2003): Based on the assessment performed in 2002, the SCSA maintained the recommendations endorsed in 2002, considering that decreasing effort and increasing length at first capture are independent and complementary management measures to reach the management objectives. Moreover, the SCSA was informed that a French longliner targeting hake has started operating in the sub-area and it recommended its monitoring to be included in the next year assessment.

FISHERIES: Merluccius merluccius is one of the most important species in the Geographical Sub-Area 9, considering both the amount of catch and commercial value. It is fished with different strategies and gears (bottom trawling, gill nets, hooks). Within the area, several fleets operating from the different ports exploit the species. The fishing pattern changes among the ports mainly due to the major use of one or other methods of capture.

The fishing pressure in the fishing grounds closer to each port is quite different. About 150 trawlers and a more limited number of vessels belonging to the artisanal fleet exploit the species. Annual landings in the area are around 500 tonnes.

Discard of undersized individuals of the species has been assessed for particular subareas and can be considered important. However, in some areas, a reduction of discards and of landings of undersized individuals did recently occur due to enforcement of controls.

SOURCE OF MANAGEMENT ADVICE: Data sources were trawl-surveys (national and MEDITS programmes) as well as Catch Assessment Surveys that include data collection of size structure of the catches. Length Cohort Analysis and Yield-per-Recruit analysis were used to assess the status of the stocks in the area as well as similations of changes of mesh size. All the analysis were done under different assumptions regarding natural mortality.

STOCK STATUS: In the 2003 assessment a wider area than in 2002 has been considered, covering almost all the sub-area 9. The species is now considered to be overexploited. Catch rates and total catches have shown in general negative trends during the last ten years. The current level of the Spawning Stock Biomass if compared with the pristine S.S.Biomass is considered in general too low, suggesting a risk of recruitment overfishing. However, standing stock size estimated through trawl-surveys suggests an increase in biomass of the species in most of the sub-areas of Geographical Sub-Area 9. The contradiction between the trends observed from trawl-surveys and commercial data can be explained at least in part by changes in the target in the case of some fleet segments.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS: Data for this assessment proceed from a year of monitoring landings on a monthly basis (year 2000). In each port with a fleet exploiting the European hake, monthly data on landings and size composition were collected. This allowed the construction of the size structure of the total annual catch by port and gear. A Length Cohort Analysis was utilised in order to estimate the fishing mortality vector and the number of individuals at sea by size. Successively, the contribution to each gear to the F vector was calculated. Two different assumptions as regards to the natural mortality were included in the analysis. A first analysis was performed assuming a constant value of M. In a second analysis, a vector of M assuming an inverse relationship with age was used. Forecast analysis assuming equilibrium were successively performed in order to evaluate the consequence of changes in fishing pressure and in selectivity.

The different trends of biomass between trawl surveys and commercial landings could be explained by the fact that fishermen in the recent years do not concentrate in nursery areas where density is higher, this can produce a reduction in commercial catch rates. This is reflected by a change in the length frequency distribution of commercial landings in some ports.

A status of growth overfishing is confirmed by this study. The species length at first capture is too low and fishing pressure very high. The current surviving fraction of the Spawning Stock Biomass (%SSB0) in both cases (assuming a constant low M and with M inversely related with age) is extremely reduced, indicating a real danger of recruitment overfishing for the stock.

The necessary reduction of fishing mortality should be of about 70% if the current mesh size is maintained. By enlarging the cod-end mesh size to 60 mm (stretched mesh size) the reduction, in order to drive spawning biomass to a safer level (about 30% of pristine stock), should be of about 60%. At the current very high levels of fishing pressure, simulations show that an enlargement of the legal mesh size up to 60 mm would produce a long term improvement of more than 30% in yield per recruit while the improvement is considered negligible as regards to the Spawning Stock survival.

The reduction of fishing mortality can be obtained through a drastic reduction of fleet capacity or fishing activity. Alternatively this reduction could be obtained by establishing protected areas where young individuals are densely concentrated.

SCSA COMMENTS AND ADVICE: The SCSA endorsed the diagnosis of overexploitation and expressed concern for the low level of SSB which is well below the generally accepted safe biological levels. In consequence the SC recommended a reduction of 60% of fishing mortality and an improvement of the exploitation pattern. The reduction of fishing effort, either through a drastic reduction of fleet capacity or in fishing activity, is in this case more effective for a management goal of a spawning stock biomass enhancement. A safer value for the % SSBo (of about 30%) can be obtained as soon as the new equilibrium will be reached. The enlargement of the legal mesh size, up to 60 mm, if not combined with fishing mortality reduction, determine a modest improvement of the Spawning Stock Biomass while producing a substantial improvement in Yields per recruit.

A final statement is necessary here, related to the important fleet reduction that has occurred in the last 3 years (up to 30% in some ports). It is likely that this fact had produced a noticeable reduction of the fishing mortality reported in the assessment. In fact, available data used for the assessment of the stock status corresponds to year 2000 situation and this reduction could not be taken under consideration in the analyses presented here. Hence, future assessments, discounting this reduction and using new data proceeding from the fisheries, is expected to show a less critical situation regarding the current stock status.

FISHERIES: Mullus barbatus is among the most valuable commercial species in the area and make part of a species assemblage that is the target of the bottom trawling fleets that operate near shore and a prime target in some particular periods when the species in densely concentrated near the coast. It is caught mainly with three different variants of the bottom trawl net. The fishing pressure on the species changes in the different sub-areas of the Geographical Sub-Area 9 depending on the consistency of the fleets that exploit the different grounds as well as on their traditional targets. Mullus barbatus catches are higher during the post-recruitment period (from September to November). About 150 vessels exploit the species. Annual landings are around 350 tonnes. Discard of undersized individuals is in general negligible, due to the fact that immediately after recruitment, small sized individuals are still concentrated inside the 3 miles stripe forbidden for trawling activities. Hence, some illegal captures do occur.

SOURCE OF MANAGEMENT ADVICE: Data proceed from trawl-surveys (national and MEDITS programmes) as well as from Catch Assessment Surveys that includes data collection of size structure of the catches. Length Cohort Analysis, Composite Production Models and Yield-per-Recruit analysis were used for assess the status of the stocks in the area. Assessments were performed separately for different operational units present in the area.

STOCK STATUS: The species is considered fully exploited and in some areas overexploited, depending on the fishing grounds where the different fishing fleets operate with different levels of fishing effort. The current level of the Spawning Stock Biomass if compared with the pristine S.S.Biomass is considered too low, suggesting a risk of recruitment overfishing. Catch rates and total catches do not show any trend during the last ten years. However, standing stock size estimated through trawl-surveys suggests an increase in biomass of the species in most of the sub-areas.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS (2002): Management measures should include spatial and temporal closures, effort limitation, a minimum landing size, gear modifications, quotas and market restrictions. A total closure of the 3 miles in order to protect juveniles immediately after recruitment was recommended.

SCSA COMMENTS AND ADVICE: Based on the 2002 assessment the SCSA kept the recommendations provided last year, i.e. reduction of fishing effort especially on the areas and season where and when recently recruited juveniles are concentrated. This can be obtained through the enforcement of a seasonal fishing ban of a period during the late summer and early autumn. This management measure should also produce a shift in the size of first capture.

FISHERIES: Mullus barbatus is among the most valuable commercial species in the area and make part of a species assemblage that is the target of the bottom trawling fleets which operate near shore. No commercial catch data and no information on the fleets were reported to the demersal WG.

SOURCE OF MANAGEMENT ADVICE: Trawl survey data from MEDITS and SAMED EU projects. The indices of abundance (weight and number per square km by swept area method), size composition at sea by sex, sex ratio, maturity growth, natural and total mortality. The Length frequency analysis, Chen & Watanabe vector, Alagaraja formula, length convrted catch curve, simulation of different scenarios using a pool dynamic model.

STOCK STATUS: Full exploitation and a growth overfishing can be assumed for the species. No significant trend in biomass abundance estimates.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS: Data collected during MEDITS trawl surveys from 1994 to 2001 were used to estimate abundance indices, biological and demographic parameters applying the standardised protocols adopted in the SAMED project. Moreover, the consequences of changes in the exploitation scenarios (total mortality and gear selectivity) were simulated by a dynamic pool model in which stochasticity was introduced.

The abundance indices (number and weight per km2) did not show any temporal trend. The results from the model showed that increasing the size at first capture would produce less advantage then decreasing total mortality. Under a conservative hypothesis (length at 50% of maturity of 140 mm), the performed analysis highlighted, in the current scenario, a level of 12% in the ratio between average Spawning Stock Biomass and average virgin Spawning Stock Biomass. As MEDITS bottom trawl surveys were carried out during the spawning season of the species, no significant trend of the abundance indices would indicate a stable condition for the spawner’s fraction of the population.

The rather constant trawl survey biomass trend coupled with the indications derived from the dynamic pool model, could imply that the self renewal of the stocks is not compromised despite of the high total mortality (more than twofold the natural mortality). Growth overfishing can be assumed for the species.

A reduction of 10-15% of the total mortality, which could drive in a more save position the SSB/SSB0 (the ratio between average Spawning Stock Biomass and average virgin Spawning Stock Biomass), could be probably obtained enforcing the area and temporal closures currently applied.

SCSA COMMENTS AND ADVICE: The SC endorsed the WG recommendation of reducing 10-15% of the total mortality, which could drive in a more save position the SSB/SSB0. This could be obtained enforcing the already existing permanent spatial closures complemented if necessary with temporary closures. Notwithstanding the stable trend or the relative aboundance index the SC indicates that it does not say anything on the sustainability of the stock.

FISHERIES: The main demersal resources are Mullus barbatus, Trachurus trachurus and Parapenaeus longirostris, Sparids such as Pagellus acarne. The contribution of this species in the landings of demersal species is between 40% and 50%.

The exploitation is carried out by coastal fleet composed mainly by trawlers. This fleet operates in the proximity of the base ports and the trips have duration between one and three days. The number of boats varies between 90 and 120 depending on the year and the fishing activity is carried out at depth less than 200 m.

SOURCE OF MANAGEMENT ADVICE: Monitoring of resources is based on landing statistics, biological data collected in the frame of a sampling programme developed in the two main landing ports. An analysis of length frequency distribution obtained from sampling of landings has been performed by means of analytical models (LCA) for the main resources exploited by the Mediterranean fleet of Morocco (geographic subarea 3).

WG MANAGEMENT ADVICE AND RECOMMENDATIONS: The Y/R analysis was utilised to test the behaviour of the populations to different exploitation levels. A situation of overexploitation has been detected. The sampling ports (Nador and Alhoceima) represent 86% of the total demersal Morocco Mediterranean landings. There are no discards. The season of recruitment was detected by analysis of monthly length frequency distribution. The catch of other gears except trawl-net is negligible. A reduction of the fishing effort in coastal areas was recommended, and this could be achieved by transferring part of the fishing effort to more offshore fishing grounds.

SCSA COMMENTS AND ADVICE: The SC endorsed the WG assessment and recommendation; however the SC drew up the attention of the WG regarding the necessity to include figures when a recommendation is made. In this case, taking into consideration the working paper submitted at the WG the SC considered that a reduction of 60% of current effort should be recommended. The SC also recommended to use also a more conservative reference point, such as F0.1, together with the Fmax.

FISHERIES: The red shrimp (Aristeus antennatus) is one of the most important resources of bottom trawling in Alboran Sea. It is fished on the slope between depths of 400 to 800 m. Landings in the period 1976-2001 were around 300 with a maximum of 517 t in 1991 and a minimum in 2001 115 t. Mean size in the landings was 27 mm CL and the catches in the last three years have decreased since the most recent peaks by about 50%.

SOURCE OF MANAGEMENT ADVICE: The state of the fishery of the Red shrimp considering the average 2000-2002 years and the whole population (females and males together) was analysed. Assessment of the exploited resource was carried out using length and age based methods (LCA and VPA) and yield per recruit analysis (Y/R). Size length catches were transformed into age data and a Pseudochort Analysis was performed.

STOCK STATUS: Results showed a stable fishery based on adults specimens. The VPA revealed that the mean age of the catch was greater than the mean age of the stock, however, the Y/R curves in all areas pointed to an overfishing scenario. Moreover, a very high fishing effort on the spawning stock biomass was detected.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS: Yield per Recruit analysis shows a lower exploitation level. Yield per Recruit analysis showed an optimum effort close to half of the current level. A transition analysis of 15 years with a reduction effort factor of 25% in the first year could bring the biomass of the stocks up to 35% higher than the current value. As a general trend the mean length of the catch was larger than the size of first maturity. Fishing mortality by age have an increasing trend from year class 2 to the oldest, probably the age class 0 has a low accessibility. The recommendation was to keep the current level of effort and if possible to reduce it.

SCSA COMMENTS: The SC noted the state of full exploitation and that the current Biomass is about 13% of the Virgin Biomass. A 25% reduction of the effort could bring the biomass of the stock up to 35% higher than the current value in 3 years. The SC endorsed the WG recommendation of keeping the current level of effort and if possible to reduce it as indicated by the analysis.

FISHERIES: The red shrimp (Aristeus antennatus) is one of the most important resources of bottom trawling in the Balearic Islands. It is fished on the slope between depths of 400 to 800 m. In biomass, it represents an average of 5% of the overall catches, but its economic value is 30% of the total earnings of the fishery. The trawl yields varied between 3 and 14 kg/h. The highest yields occurred in winter and spring. The decline of the sizes at first capture in 1997 and the increase of juveniles in the catches can be interpreted as a change in the fishery strategy, which has increased the exploitation effort on the small sizes. The average landings in the last three years has been 170 t. Mean CPUE varied from 25 to 45 kg per vessel and day. Mean size in landings was 29 mm CL.

SOURCE OF MANAGEMENT ADVICE: The state of the fishery of the Red shrimp considering the average 2000-2002 years and the whole population (females and males together) was analysed. Assessment of the exploited resource was carried out using length and age based methods (LCA and VPA) and yield per recruit analysis (Y/R). Size length catches were transformed into age data and a Pseudochort Analysis was performed.

STOCK STATUS: The VPA revealed that the mean age of the catch was greater than the mean age of the stock, however, the Y/R curves in all areas pointed to an overfishing scenario. Moreover, a very high fishing effort on the spawning stock biomass was detected.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS: Landings keep up similar levels for the three years. Nevertheless it has been detected a smooth decreasing trend. Yield per Recruit analysis shows a full exploitation and an optimum effort close to half of the current level. A transition analysis of 15 years with a reduction an effort factor of 25% in the first year could bring the biomass of the stock up to 32% higher than the current value.

As a general trend the mean length of the catch was larger than the size of first maturity. Fishing mortality by year have an increasing trend from year class 2 to the oldest, probably the age class 0 has a low accessibility. Catches in the last three years have decreased since the most recent peaks by about 50%. The recommendation was to keep the current level of effort and if possible to reduce it.

SCSA COMMENTS: The SC noted the state of full exploitation and that the current Biomass is about 16% of the Virgin Biomass. A 25% reduction of the effort could bring the biomass of the stock up to 32% higher than the current value in 3 years. The SC endorsed the WG recommendation of keeping the current level of effort and if possible to reduce it as indicated by the analysis.

FISHERIES: The red shrimp is one of the most important resources of bottom trawling in this sub area. It is fished on the slope between depths of 400 to 800 m. Recent average annual landings were 114 t. Mean size in the landings was 26 mm CL.

SOURCE OF MANAGEMENT ADVICE: The state of the fishery, considering the average 2000-2002 years and the whole population (females and males together) was analysed. Assessment of the exploited resource was carried out using length and age based methods (LCA and VPA) and yield per recruit analysis (Y/R). Size length catches were transformed into age data and a Pseudochort Analysis was performed.

STOCK STATUS: The VPA revealed that the mean age of the catch was greater than the mean age of the stock, however, the Y/R curves in all areas pointed to an overfishing scenario. Moreover, a very high fishing effort on the spawning stock biomass was detected.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS: Results of the assessment showed a full exploitation based on adults specimens. Landings keep up similar levels for the three years analysed, nevertheless a smooth decreasing trend have been detected. Yield per Recruit analysis showed an optimum effort close to half of the current level. A transition analysis of 15 years with a reduction effort factor of 25% in the first year, could bring the biomass of the stocks up to 36% higher than the current value.

As a general trend the mean length of the catch was larger than the size of first maturity. The recommendation was to keep the current level of effort and if possible to reduce it.

SCSA COMMENTS: The SC noted the state of full exploitation and that the current Biomass is about 12% of the Virgin Biomass. A 25% reduction of the effort could bring the biomass of the stock up to 36% higher than the current value in 3 years. The SC endorsed the WG recommendation of keeping the current level of effort and if possible to reduce it as indicated by the analysis.

FISHERIES: The main demersal resources are Mullus barbatus, Trachurus trachurus and Parapenaeus longirostris, Sparids such as Pagellus acarne. The contribution of this species in the landings of demersal species is between 40% and 50%.

The exploitation is carried out by coastal fleet composed mainly by trawlers. This fleet operates in the proximity of the base ports and the trips have duration between one and three days. The number of boats varies between 90 and 120 depending on the year and the fishing activity is carried out at depth less than 200 m.

SOURCE OF MANAGEMENT ADVICE: Monitoring of resources is based on landing statistics, biological data collected in the frame of a sampling programme developed in the two main landing ports. An analysis of length frequency distribution obtained from sampling of landings has been performed by means of analytical models (LCA) for the main resources exploited by the Mediterranean fleet of Morocco.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS: The Y/R analysis was utilised to test the behaviour of the populations to different exploitation levels. A situation of full exploitation was detected. The sampling ports (Nador and Alhoceima) represent 86% of the total demersal Morocco Mediterranean landings. There are no discards. The season of recruitment was detected by analysis of monthly length frequency distribution. The catch of other gears except trawl-net is negligible. Horse mackerel in Morocco is caught almost only by demersal trawlers.

The WG recommended not to increase the fishing effort.

SCSA COMMENTS AND ADVICE: No SC comments. The SC recommended to the WG that assessment should be presented on a species by species basis. The SC also recommended to use also a more conservative reference point, such as F0.1, together with the Fmax.

FISHERIES: The main demersal resources are Mullus barbatus, Trachurus trachurus and Parapenaeus longirostris, Sparids such as Pagellus acarne. The contribution of this species in the landings of demersal species is between 40% and 50%.

The exploitation is carried out by coastal fleet composed mainly by trawlers. This fleet operates in the proximity of the base ports and the trips have duration between one and three days. The number of boats varies between 90 and 120 depending on the year and the fishing activity is carried out at depth less than 200 m.

SOURCE OF MANAGEMENT ADVICE: Monitoring of resources is based on landing statistics, biological data collected in the frame of a sampling programme developed in the two main landing ports. An analysis of length frequency distribution obtained from sampling of landings has been performed by means of analytical models (LCA) for the main resources exploited by the Mediterranean fleet of Morocco (geographic subarea 3).

WG MANAGEMENT ADVICE AND RECOMMENDATIONS: The Y/R analysis was utilised to test the behaviour of the populations to different exploitation levels. The pink shrimp shows a situation of underexploitation. The sampling ports (Nador and Alhoceima) represent 86% of the total demersal Morocco Mediterranean landings. There are no discards. The season of recruitment was detected by analysis of monthly length frequency distribution. The catch of other gears except trawl-net is negligible.

The WG recommended transferring part of the fishing effort exerted in coastal areas to deeper fishing grounds.

SCSA COMMENTS AND ADVICE: No SC comments. The SC recommended that the WG combines assessments for males and females in order to have an assessment of the stock as a whole and give an advice on it.

FISHERIES: Red shrimp Aristaeomorpha foliacea is caught only by deep water trawling. In the last twelve years an increase from 59 to 70 trawlers fishing on red shrimps was observed in the geographical sub-area.

SOURCE OF MANAGEMENT ADVICE: The assessment was carried out by Relative Y/R analysis using exploitation rate (E) as indicator of fishing effort. Data were collected during trawl survey programs. The current level of E was derived from Z and M estimates

STOCK STATUS: According to this analysis the current value of E is very close to Emax.

WG MANAGEMENT ADVICE AND RECOMENDATIONS: No management advice was given.

SCSA COMMENTS AND ADVICE: Based on the assessment of 2002 the SC kept the recommendation of not to increase the effort. The SC requested the WG to provide figures on current E.

FISHERIES: Nephrops norvegicus is a very important species with a very high commercial value. It is the target of a variable fraction of all the fleets operating in the Geographical Sub-Area 9 during the whole year. Annual landings in the area do not reach 100 tonnes. The species is caugth with the traditional Italian bottom trawl net at depths between 250-500 m.About 40 vessels exploit the species in the area. No discards of the species exist being the size of almost all the individuals caught around or beyond the legal size.

SOURCE OF MANAGEMENT ADVICE: Data were collected during trawl-surveys (national and MEDITS programmes) as well as from Catch Assessment Surveys that includes data collection of size structure of the catches, 1985-2001. Length Cohort Analysis and Yield-per-Recruit analysis were used to assess the status of the stocks in the area.

STOCK STATUS: The species is considered to be fully or underexploited, depending on the fishing grounds exploited by the different fishing fleets with different rates. Catch rates showed in general positive trends during the last ten years. The current level of effort and fishing pattern looks adequate in order to warrant the sustainability of the resource and fishery.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS: No specific recommendation.

SCSA COMMENTS AND ADVICE: No SC recommendation. The SC was informed that the fishing effort targeting on Norway lobster has increased recently.

SMALL PELAGIC SPECIES

FISHERIES: Anchovy and Sardine are the main target species of the purse seine fleet in the Northern Alboran Sea. Other accompanying species with lower economical importance are also caught such as: Horse mackerel (Trachurus spp), mackerel (Scomber spp), Atlantic saury (Scomberesox saurus) and gilt sardine (Sardinella aurita). In the South-Mediterranean Region (from Gibraltar Strait to Cape of Gata) the fleet continuously decreased in the last two decades, from more 230 vessels in 1980 to 120 in 2001. The present fleet has a mean GRT of 17.2. Only Malaga Bay fishing area, which represents 85% of total landings, has been considered by the WG. After 1993 minimum a slight recovery of landings was observed in 1996, but a new diminution occurred in the following years, reaching a minimum in 2000. Finally, a strong increment of landings was recorded in 2001, together with an increase of CPUE values, which reached this year the highest level since 1995, despite the autolimitations in the volume of landings decided by the fishermen in order to maintain the market prices.

SOURCE OF MANAGEMENT ADVICE: Information from fishery: landings and CPUE trends. Acoustic survey carried out 2000 to 2001.

STOCK STATUS: Biomass estimation for Malaga Bay in 2001 survey (13210 tonnes) represented an important increment respect to the previous year situation (1716 tonnes). Since most of the stock is concentrated in Malaga Bay this estimation can be considered as representative of the whole northern Alboran area.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS (2002): Since that fishing effort was already significantly reduced in number of vessels (from 185 in 1985 to 120 in 2001), and taking into account the good 2001 recruitment, it would be advisable to maintain the current level of fishing effort. However, taking into account the important fluctuations of this stock and the few age classes composing the catches (practically only 0 and 1), it would be necessary to continue the monitoring of this stock.

SCSA COMMENTS (2002): The SC endorsed the assessment and recommended that, although the image of the stock situation has changed because of the very good last year recruitment, the SC recommended maintaining the current level of fishing effort.

SCSA COMMENTS (2003): Since no assessment was submitted in 2003, the SC requested the WG to up date this assessment. In addition the SC was informed that a temporarly fishing ban for purse seiners has been enforced during spring in the last years.

FISHERIES: Anchovy and sardine are the main target species of the purse seine fleet in the Northern Spain. Sardine is the species with the highest amount of catch; on the other hand, anchovy is the most sought due to its economical value. The present fleet has 191 purse seiners, a 12% smaller than the previous year, with a mean GRT of 32.60. A peak of landings of around 22000 tonnes was found in 1994, but then decreased to an overall value of 6000 tonnes in year 2000; this value is the lowest for the last fiveteen years. The anchovy landings represent 80% of the total catch anchovy in Spanish Mediterranean.

SOURCE OF MANAGEMENT ADVICE: Acoustic surveys carried out from 1990 to 1993, and from 1995 to 2001, between La Nao Cape and Creus Cape (Tramontana Region).

STOCK STATUS: The period in which the surveys were carried out corresponds to the recruitment season of the species. The most important recruitment area is located between Barcelona and the south of the Ebro River Delta. For this area, the surveys suggested that the recruitment was very low from 1996 to 2000, but the population appeared to have recovered in 2001 to amounts close to the half of those found in 1992, when the highest value was estimated. The estimated biomass for the whole area in 2001 (27000 tonnes) was two times higher than that in 2000.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS (2002): Taking into account the important fluctuations observed in the recruitment, which have a direct effect on the total biomass of the stock, it was recommended that current levels of fishing effort should be maintained.

SCSA COMMENTS (2002): The SC endorsed the assessment and recommended not to increase the fishing effort.

SCSA COMMENTS (2003): Since no assessment was submitted in 2003, the SC requested the WG to update this assessment. In addition, the SC was informed that a temporarly fishing ban for purse seiners has been enforced during spring in the last years.

FISHERIES: Gulf of Lions and North Catalonian anchovy stock is shared by Spanish and French fleets. Both France and Spain are sharing this stock with a predominance of Spanish purse seiners fishing at night with lights in the Gulf of Lions. At the moment, there is no conflict with French trawlers that operate only during daytime. The annual catch is between 5000 and 6000 tonnes. The production, however, is regulated by market demand. When market prices are low, pelagic trawlers shift their activities toward demersal resources, which are overexploited. Echo-integration methodology is used annually since 1993 in the Gulf of Lions, during summer, in order to estimate the importance and the variations of resources of anchovy, sardine and other commercial pelagic species. The state of the anchovy population in the Gulf of Lions appears to improve, since in the last two years an increase in the reproductive biomass has been observed, (48000, 70000 and 112000 t. respectively in 1999, 2000 and 2001). On the other hand, for sardine, the biomass seems to be stable.

SOURCE OF MANAGEMENT ADVICE: Biomass and abundance indices obtained by direct methods from French and Spanish surveys (from 1990 to 1993 and from 1995 to 2001) are analysed and combined, as well as catches and fishing effort series for 1993-2001

STOCK STATUS: High level of biomass and relatively low catches

WG MANAGEMENT ADVICE AND RECOMMENDATIONS (2003): Taking into account the high level of biomass available at this time and the relatively low catches on this shared stock, the WG recommended to maintain the fishing effort and to continue evaluating yearly the state of the stock, due to the variability of the recruitment of the anchovy that can result in important natural fluctuations in the abundance of the stock.

SCSA COMMENTS: The SC endorsed the assessment and recommended not increasing the fishing effort.

FISHERIES: Anchovy (Engraulis encrasicolus, L.) is one the most important commercial species of the Adriatic Sea. The small pelagic fishery is particularly diffuse in the Northern and Central Adriatic Sea and sardine is fished by the fleets of Italy, Slovenia and Croatia. The Italian fleet in the Northern and Central Adriatic is composed of about 132 (66 couples) pelagic trawlers (volante) mainly operating from Trieste to Ancona and of about 36 lampara vessels (purse seiners with light) which operates mainly in the Central Adriatic Sea. Fishing regime (regulations in force in Italy): Since 1988 closing fishing season concerning trawling is also applied to mid-water pair trawlers during summer (about 45 days of closing season between July and September). Closing fishing season is not applied for the purse seiners. Fishing activity is suspended during week-end.

The estimated stock biomass of Adriatic anchovy by VPA, carried out in the context of FAO-Adriamed-SP research programme, showed strong fluctuations during the observed period (1975-2002). After the collapse occurred in 1987 the recovery of the stock biomass shows now a positive trend. Nevertheless, the biomass level has not reached the previous high values.

SOURCE OF MANAGEMENT ADVICE: SAC Assessment form VPA tuned with CPUE (Laurec-Shepherd method)

STOCK STATUS: The estimated stock biomass of Adriatic anchovy by VPA showed a strong fluctuation during the observed period (1975-2002). Collapse occurred in 1987 and the recovery of the stock biomass shows a positive trend. Nevertheless, the biomass level has not reached the previous higher values. The present amount of catches is about the 22% of estimated biomass.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS: Given this situation and considering also that the present amount of catches (22,150 tonnes, average catch on the period 2000-2002) is about the 22% of the estimated biomass, the current level of fishing effort should not be increased.

SCSA COMMENTS: The SC endorsed the assessment and recommended not increasing the effort. In this context, the SC also considered that GFCM Members should provide updated figures on size and characteristics of fishing fleets and gear exploiting this stock in order to stablish the current level of fishing effort. The SC noted that in the frame of the ADRIAMED project for the first time a joint analytical assessment covering the whole northern Adriatic and an echosurvey in the northern part were conducted. The SC recommended combining the outcomes of both approaches in the forthcoming assessment.

FISHERIES: A purse seining fleet based in the ports of Alexandroupolis, Kavala and Thessaloniki (Greece) operates in the area. No available data on fishing effort, trends in catches, landings and discards.

SOURCE OF MANAGEMENT ADVICE: The DEPM was applied for estimating the anchovy spawning biomass at an area indicated between the Thraki mainland in the north and the isles of Samothraki and Thasos in the south.

STOCK STATUS: The estimated spawning biomass, in 1999, yielded 13180 tonnes

WG MANAGEMENT ADVICE AND RECOMMENDATIONS (2002): No comments

SCSA COMMENTS (2002): The SCSA recommended to the WG to extend the study area and to include the whole spawning ground of the stock in order to increase the precision of the estimation. The SCSA also recommended a standardisation of the methodology used by different groups of the small pelagic WG operating in the same area. Such approach would provide a more accurate evaluation of the stock spawning biomass.

SCSA COMMENTS (2003): Since no assessment was submitted in 2003, the SC requested the WG to update this assessment. The SC has been informed that information on fleets, catch trends and discarded catches exist and in consequence recommended that this information be made available to the WG.

FISHERIES: Anchovy and Sardine are the main target species of the purse seine fleet in the Northern Alboran Sea. Other accompanying species with lower economical importance are also caught such as: Horse mackerel (Trachurus spp), mackerel (Scomber spp), Atlantic saury (Scomberesox saurus) and gilt sardine (Sardinella aurita). In the South-Mediterranean Region (from Gibraltar Strait to Cape of Gata) the fleet continuously decreased in the last two decades, from more 230 vessels in 1980 to 120 in 2001. The present fleet has a mean GRT of 17.2. Only Malaga Bay fishing area, which represents 85% of total landings, has been considered by the WG. A peak of landings of around 6000 tonnes was found in 1991-1992, but then decreased to an overall mean value of 1000-2000 tonnes during 1994-1998. From 1998 onwards, both landings and CPUE showed an increasing trend, reaching in 2000 and 2001 CPUE values higher than those observed in previous years

SOURCE OF MANAGEMENT ADVICE: Information from fishery: landings and CPUE trends.

STOCK STATUS: Unknown

WG MANAGEMENT ADVICE AND RECOMMENDATIONS (2002): Taking into account information available it does not seem necessary to recommend any reduction of fishing effort on this stock

SCSA COMMENTS (2002): No comments

SCSA COMMENTS (2003): Since no assessment was submitted in 2003, the SC requested the WG to up date this assessment. In addition the SC was informed that a temporarly fishing ban for purse seiners has been inforced during spring in the last years.

FISHERIES: Sardine is one of the most exploited species in the Moroccan Mediterranean. The landings of this species represent around 80% of the total small pelagics landings. At present the species is exploited by 141 purse seiners, of a mean gross tonnage of 40 tx and mean horsepower 450 cv. The vessels operate all the year, 5-6 days per week, 12 to 15 hours at sea per fishing day. During one fishing day two or three fishing operations can be carried out. Sardine landings have undergone important fluctuations during the period 1984-2000, with a maximum around 28000 toones in 1987, and a minimum value around 9300 tonnes in 1998. The fishing effort (number of fishing days*GRT) has also fluctuated during 1992-2000, with a maximum in 1993 and a minimum in 1998. In 1999 and 2000 the fishing effort increased.

SOURCE OF MANAGEMENT ADVICE: The method used was LCA, applied to annual length frequency distributions for the period 1990-2001 collected from commercial landings. The sampling port was Al Hoceima, which is the most important fishing port regarding sardine landings in the Moroccan Mediterranean. Data on von Bertalanffy growth parameters are those estimated during Spanish 1998 echo surveys in the Alboran Sea.

STOCK STATUS: Sardine biomass has decreased during the period 1993-1997 but later, since 1998, a positive trend has been observed. Results indicate that the optimum fishing mortality F0,1 corresponds to 60% of the current fishing mortality. The stock is thus overexploited. The Fmax could not be estimated because the resulting Y/R curve was asymptotic.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS (2002): Neither management advice nor recommendations were proposed

WG MANAGEMENT ADVICE AND RECOMMENDATIONS (2003): The production of sardine in the Mediterranean coast of Morocco is estimated at 14000 mt/year landed by a fleet of 141 boats carrying out more than 15000 trips per year. According to the biomass estimation made in the Institute of Nador by length cohort analysis, the stock of sardine presended a strong decrease from 1992 to 1997 and a trend of slightly increasing biomass from 1998 to 2001. The higher mortality rate was observed for speciments larger than 16 cm.

SCSA COMMENTS: The SC recommended continuing further analysis with the available data. Furthermore, considering the decreasing trend of catches despite the increasing fishing effort on this stock and the recommendations provided by the marrocan scientists[2] to the WG, the SC recommended the WG to analyse in depth this recommendations.

FISHERIES: Anchovy and sardine are the main target species of the purse seine fleet in the Northern Spain. Sardine is the species with the highest amount of catch; on the other hand, anchovy is the most sought due to its economical value. The present fleet has 191 purse seiners, a 12% smaller than the previous year, with a mean GRT of 32.60. Sardina landings have increased from 70´s, reaching a maximun of 53000 tonnes in 1994. For the last years there was a decrease reaching 38000 tonnes in year 2000.

SOURCE OF MANAGEMENT ADVICE: ECOMED acoustic surveys carried out from 1990 to 1993, and from 1995 to 2001, between La Nao Cape and Creus Cape (Tramontana Region).

STOCK STATUS: From 1990 to 2001, the estimated biomass fluctuated from 200000 tonnes in 1992 to 50000 tonnes in 2000. The estimation for 2001 was 97000 tonnes, which was double than in the previous year. The most important recruitment corresponded to the years 1991 and 1992, whereas the lower values were found in 2000 and 2001.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS (2002): Taking into account the present level of biomass and catches, as well as the low level of recruitment detected in the two last years, it would be advisable not to increase the current level of fishing effort.

SCSA COMMENTS (2002): The SC endorsed the assessment and recommendations.

SCSA COMMENTS (2003): Since no assessment was submitted in 2003, the SC requested the WG to update this assessment.

FISHERIES: Sardine is exploited in the Gulf of Lions by 120 mid water trawlers shifting toward demersal ressources when the market prices are low and by 8 purse seiners operating in the zone. The number of the involved trawlers changes every month according to the targeted species. The mean fished quantity reported in the relative stock assessment form, for the period 1999-2001, arises to 9000 t.

SOURCE OF MANAGEMENT ADVICE: Starting from 1993, echo-integration methodology is used annually in the Gulf of Lion, in order to estimate the importance and the variations of sardine stock and other commercial pelagic species.

STOCK STATUS: The resource is reported as moderately exploited.

WG MANAGEMENT ADVICE AND RECOMENDATIONS: From these results the species biomass is reported to be stable and the average value for the period 1999-2001 was estimated to be about 76000 t.

SCSA COMMENTS AND ADVICE: The SCSA recommended to continue the investigation on biomass and fishing effort estimation.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS (2003): Biomass evaluations from six echo-surveys carried out from June 1998 to July 2002 in the Strait of Sicily were presented. Both sardine and anchovy populations experienced quite large inter-annual fluctuations, from about 36,000 t in July 2000 to 6,000 t in 2002 for sardine and 7,000 t in 1998 to 23,000 t in 2001 for anchovy. Specifically for anchovy this evidence would suggest, taking also into account the age structure of the catches (low proportion of juveniles), the importance of environmental factors variability on yearly recruitment success. Acoustic evaluations are largely consistent with landings (from purse seiners and midwater pair trawlers) recorded in Sciacca (the most important base port in the M.U. 16 for the small pelagics landings) during the year following the evaluation campaigns. The recent decreasing trend in sardine biomass suggest to consider the risks connected to possible negative effects on this population, resulting from wintertime (from January to March) pressure of other fishing gears on larval stages.

SCSA COMMENTS AND ADVICE: According to the results presented on the local sardine stock, the SCSA recommended that the WG presents an assessement form where the time series of data on biomass estimation, the fleet characteristics and catch data will be included, allowing the proper assessment of the sardine and anchovy stock and the formulation of some management measures. The impact of local fisheries directed to larval or juvenile speciments of this species should be carefully evaluated and the results should be presented in the next meeting of the WG.

FISHERIES: Sardine (Sardina pilchardus, Walb.) is one of the most important commercial species of the Adriatic Sea. The small pelagic fishery is particularly diffuse in the Northern and Central Adriatic Sea and sardine is fished by the fleets of Italy, Slovenia, and Croatia.The Italian fleet in the Northern and Central Adriatic is composed of about 132 (66 couples) pelagic trawlers (volante) mainly operating from Trieste to Ancona and of about 36 lampara vessels (purse seiners with light) which operates mainly in the Central Adriatic Sea.

Fishing regime (regulations in force in Italy): Since 1988 closing fishing season concerning trawling is also applied to mid-water pair trawlers during Summer (about 45 days of closing season between July and September). Closing fishing season is not applied for the purse seiners. Fishing activity is suspended during week-end.

Trends in landings: Landed sardines decreased in the last years (1997-2001).

Discards: No information are available for the last years (2000 and 2001). In the previous period (1987-1999) an average of about 2000 t/year of discards were estimated for the Italian fleet by a specific research project.

SOURCE OF MANAGEMENT ADVICE: SAC Assessment form VPA tuned by commercial CPUE (Laurec-Shepherd method) on a 1975-2002 time series.

STOCK STATUS: The estimated stock biomass of sardine by VPA showed a peak between 1983 and 1985, then a gradual decrease appeared and the stock reached its lowest value in 1999. In 2000, and in a stronger way in 2001, the sardine estimated biomass increased. The present level of catches is about the 18% of the estimated biomass.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS (2002): Monitoring of sardine discards at sea and market strategies to increase the human consumption of sardine, to diminish discards at sea are recommended. The new research programme supported by FAO-ADRIAMED, entitled "Data Collection and Biological Sampling System on Small Pelagics in the Adriatic Sea (Adriamed-SP)" is implemented. Data collected with this project will improve assessment of small pelagics in Adriatic.

WG MANAGEMENT ADVICE AND RECOMMENDATIONS (2003): The estimated stock biomass of sardine by VPA carried out in the framework of FAO-Adriamed-SP research programme, showed a peak between 1983 and 1985, then a continuous decrease appeared and the stock reached its lowest value in 2001. Given this situation and considering also that the present level of the catches (19,300 tonnes, average catch on the period 2000-2002) is about the 19% of the estimated biomass, the current level of fishing effort should not be increased. Due to the low market demand in Italy for sardines, discards at sea may occur and hence monitoring of sardine discards at sea was suggested.

SCSA COMMENTS AND ADVICE: The SC expressed concern regarding the continous decreasing trend of biomass estimates observed during the last 20 years and in consequence, it recommended implementing more cautious measures, including reduction of fishing effort, to revert this trend and to reduce the Exploitation Rate below the current level of 0.4[3]. The SC, conscious of the fact that anchovy is the target species of the Italian fleet whilst the Slovenian, Albanian and Croatian fleets are targeting on sardine, also recommended to implement, as soon as possible, a harmonized management in the sub-area for small pelagics. In this context, the SC also considered that concerned GFCM Members should provide updated figures on size and characteristics of fishing fleets and gear exploiting this stock in order to establish the current level of fishing effort.

FISHERIES: A purse seining fleet based in the ports of Volos, Chalkis, Corinthos and Patras (Greece) operates in the area. No available data on fishing effort, trends in catches, landings and discards.

SOURCE OF MANAGEMENT ADVICE: The document includes biomass estimation of sardine stocks en central Aegean and eastern Ionian Seas, based on DEPM.

STOCK STATUS: Total spawning biomass was estimated in 2000 to be 19.826 tonnes

WG MANAGEMENT ADVICE AND RECOMENDATIONS: No comments.

SCSA COMMENTS: The assessment was considered to be preliminary. The SCSA recommended to organise and conduct a long term programme on biomass estimation and to present a new assessment.

[1] As extracted from the report of SCSA, Nicosia, Cyprus, 3-6 June 2003.
[2] - Reduce the fishing pressure during 3 years
- Establish a temporary ban in January
- Establish closed areas in the lagune of Nador and Bay of Al Hoceima
- Ban fishing in May in the area between Kariat Arkmen and the Chafarinas Islands
[3] Refernce point for small pelagics (Patterson, K. 1992. Fisheries for small pelagic species: an empirical approach to management targets. Rev.Fish Biol.Fish.,2:321-338.

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