ASSESSMENT AND MONITORING OF THE FISHERY RESOURCES AND THE ECOSYSTEMS IN THE STRAITS OF SICILY MEDSUDMED GCP/RER//ITA MiPAAF FAO-MedSudMed CC/9/Info 5 9 th Meeting of the MedSudMed Coordination Committee Mazara del Vallo Capo Granitola Italy, 6-8 May 2 Assessment of deep water pink shrimp, Parapenaeus longirostris, in the south-central Mediterranean Sea
SAC GFCM Sub-Committee on Stock Assessment DAY MONTH YEAR Date* 6 October 2 Code* DPS99S. Authors* S. Ben Meriem, F. Fiorentino, V. Gancitano, L. Knittweis, O. Jarboui, L. Ceriola, E. Arneri Affiliation* Institut National des Sciences et Technologies de la Mer (INSTM), Tunisia; IAMC-CNR Mazara del Vallo, Italy; Ministry for Resources and Rural Affairs (MRRA), Malta GFCM Priority S Parapenaeus longirostris - DPS DPS Species Scientific name* Source: GFCM Priority Species 2 Source: - 3 Source: - Geographical area* GSA 2, 3, 4, 5 and 6 Geographical Sub-Area (GSA)* Combination of GSAs 2 3 99 - Combination of GSAs 6 - South of Sicily 5 - Malta Island 2 - Northern Tunisia SCSA
Sheet # Basic data on the assessment Date* 6 Oct Code: DPS99S. 2 Authors* S. Ben Meriem, F. Fiorentino, V. Gancitano, L. Knittweis, O. Jarboui, L. Ceriola, E. Arneri Species Scientific name* Parapenaeus longirostris - DPS Data Source 6 - South of Sicily, 5 - Malta Island, 2 - Northern GSA* Period of time* 27-29 Tunisia 2 6 - South of Sicily, 5 - Malta Island, 2 - Northern Tunisia Description of the analysis Type of data* Method of assessment* Parapenaeus longirostris - DPS LFD from commercial catches, landings data LCA, Y/R analysis Species common name* Deepwater rose shrimp Tunisian national data collection Data source* programme, EU Data Collection Framework Analen, VIT4win, Yield Software used* Sheets filled out B P P2a P2b G A A2 A3 Y Other D Z C 4 --- 4 4 3 4 4 4 3 Comments, bibliography, etc. 34 Chevailler P., Laurec A., 99. Logiciels pour l'evaluation des stocks de poisson. ANALEN: Logiciel d'analyse des donnees de capture par classes de taille et de simulation des pecheries multi-engins avec analyse the sensibilite. FAO Doc. Tech. Peches,, Suppl. 4: 24p. Fiorentino, F., Meriem, S., Bahri, T., Camilleri, M., Dimech, M., Ezzedine-Naja, S., Massa, F., Jarboui, O., Zgozi, S., 28. Synthesis of information on some target species in the MedSudMed Project area (central Mediterranean). GCP/RER//ITA/MSM-TD-5. MedSudMed Tech. Docs, 5: 67 pp. Fortibuoni, T., Bahri, T., Camilleri, M., Garofalo, G., Gristina, M., Fiorentino, F., 2. Nursery and spawning areas of deep-water rose shrimp, Parapenaeus longirostris (Decapoda:Penaeidae), in the strait of Sicily (Central Mediterranean Sea). Journal of Crustacean Biology, 3(2):67-74. Guijarro B., Massuti E., 26. Selectivity of diamond- and square-mesh codends in the deepwater crustacean trawl fishery off the Balearic Islands (western Mediterranean). ICES J. of Mar. Sci. 63: 52-67. Lleonart J., Salat J., 2. Vit4winVersion..www.faocopemed.org/es/activ/infodif.htm.
Sheet # (page 2) Comments, bibliography, etc. 3677 MEDSUDMED, 27. Spatial distribution of demersal fishery resources, environmental factors and fishing activities in GSA 5 (Malta Island). GCP/RER//ITA/MSM-TD-3. MedSudMed Technical Documents, 3: 3pp. SAMED, 22. Stock assessment in the Mediterranean. European Commission - DG XIV, Project 99/47. Final Report.
Sheet B Biology of the species Biology Somatic magnitude measured (LH, LC, etc)* CL Sex Fem Mal Both Unsexed Maximum size observed 42-46 38-4 Size at first maturity Recruitment size 2.85 3.65 5 5 to 8 Units* Reproduction season Reproduction areas Nursery areas Code: DPS99S. mm Peak summer/fall yes yes Parameters used (state units and information sources) Growth model Length weight relationship L K t Data source a b M sex ratio (mal/fem) Sex Units female male both unsexed mm 42.75 33.56 44.59.67.73.6 year -.28 -.3 -.8 Average SAMED (22) / Ben Meriem (unpubl.).29.345.33 2.4885 2.496 2.4572.57-.67.5.2.5 Comments Reproduction 658 According to Levi et al., (995) mature females are found in GSA 5 and 6 throughout the year, with a maturity peak extended from November to February, and another maturity peak in April. Ben Mariem et al. (2) reported that P. longirostris off the Tunisian coasts (GSA 2) reproduces all year along, with a peak in June-July and a minimum in winter. The stock structure of deep water pink shrimp (Parapenaeus longirostris) in the Strait of Sicily has yet to be defined. Levi et al. (995) hypothesised that there is a flux of eggs, larvae and juvenile P. longirostris from east to west due to an intermediate water current present in the region. More recently, the existence of at least two sub-populations in the northern side of the area (GSA 5 and 6) were reported by Fortibuoni et al. (2). This idea is based on the occurrence of local spawning and nursery areas, which are connected by the Atlantic Ionian Stream flow (-5 m depth). It is hypothesised that the development of larval and juveniles phases occurs in this Atlantic Ionian Stream. These local sub-populations, one on the Adventure Bank and one on the Malta Bank, are separated by a wide area, where the species abundance is scanty The sex ratio was calculated as F/(F+M) both in terms of population at sea (.57) and catch (.67)
Sheet P General information about the fishery Code: DPS99S. Data source* Tunisian National Data Collection Programme, EU Data Collection Framework Year (s)* 29 Data aggregation (by year, average figures between years, etc.)* By year Fleet and catches (please state units) Country GSA Fleet Segment Fishing Gear Class Group of Target Species Species Operational Unit * Operational Unit 2 Operational Unit 3 Operational Unit 4 Operational Unit 5 MLT ITA ITA TUN 99 E - Trawl (2-24 metres) 99 E - Trawl (2-24 metres) 99 F - Trawl (>24 metres) 99 F - Trawl (>24 metres) 3 - Trawls 3 - Trawls 3 - Trawls 3 - Trawls 34 - Demersal slope species 34 - Demersal slope species 34 - Demersal slope species 34 - Demersal slope species DPS DPS DPS DPS Operational Units* MLT 99 E 3 34 - DPS ITA 99 E 3 34 - DPS ITA 99 F 3 34 - DPS TUN 99 F 3 34 - DPS Fleet (n of boats)* Kilos or Tons 6 Tons 25 Tons 4 Tons 7 Tons Catch (species assessed) 8.2 5496 777 55 Other species caught Discards (species assessed) Discards (other species caught) Effort units Total 476 886.2 Legal minimum size EU: 2mm CL (EC 967/26) Comments 6 5 4 Tons 3 2 26 27 28 29 2 ITA Small Boat ITA Big Boat Tunisia Malta
Sheet P (page 2) Comments The main fishing areas of P. longirostris for distant (coloured) and coastal (black) Sicilian trawlers in the Strait of Sicily (modified from Levi et al. 995).
Sheet P2a Fishery by Operational Unit Code: DPS99S. Page / 4 Data source* EU Data Collection Framework OpUnit * MLT 99 E 3 34 - DPS Time series Year* 27 28 29 Catch 8 22 8.239 Minimum size Average size Lc 22.86 Maximum size 35 Fleet E-Trawl Year Catch Minimum size Average size Lc Maximum size Fleet Selectivity Remarks 93 L25 9. Selectivity parameters for 4mm square mesh net, taken from Guijarro L5 2.2 and Massuti (26; Balearic Islands). L75 2.4 Selection factor Structure by size or age Length Class Female_29 Male_29 5 6 7 8 38 44 9 7 23 72 25 786 5359 2 365 846 3 4495 3485 4 688 264 5 786 2552 6 9869 24836 7 45 46695 8 26338 6839 9 28577 224 2 64785 225589 2 746 954
Sheet P2a (Page / 4-2 sheet) Structure by size or age 22 3998 22 23 98863 7454 24 98647 8473 25 26657 38752 26 22663 7566 27 3546 249 28 7575 544 29 965 2529 3 425 3 2256 32 83 33 6423 34 879 35 927 36 37 38 39 4 4 42
Sheet P2a Fishery by Operational Unit Code: DPS99S. Page 2 / 4 Data source* EU Data Collection Framework OpUnit 2* ITA 99 E 3 34 - DPS Time series Year* 27 28 29 Catch 3248 3734 5496 Minimum size Average size Lc Maximum size Fleet Year Catch Minimum size Average size Lc Maximum size Fleet Selectivity L25 5.5 L5 7 L75 8.5 Selection factor.42 Remarks 2 Structure by size or age LC 29 Male Female 28_F 28_M 27_F 27_M 34844 82 34 74932 2 9636 97475 9567 49389 3 689325 772598 793744 723444 847899 53279 4 4228 552947 345838 376333 4942327 486499 5 526487 985795 663783 852668 227864 3222924 6 33436 752 35692 283723 3937772 4255472 7 5287276 8782243 442826 369359 3627564 462867 8 637455 28829 695257 37293873 332265 446422 9 4526858 3342823 855846 3974464 423745 45427 2 4569654 44526242 232592 2642725 427234 47679 2 3224357 475764 22948 287835 4692626 32546273 22 9674494 48864893 2268288 39466 34523 728346 23 948845 5238256 22468774 736439 79225 73589 24 3892223 59258 2873452 3392939 35334 377849 25 6369 4557385 626276 44222 93597 3865262 26 58725 389243 9969758 935824 647974 4952 27 7387 3967 49844 286536 5762245 89
Sheet P2a (Page 2 / 4-2 sheet) 28 79647 2365957 936488 75267 466 22 29 5988 4794257 83633 28962 386788 22 3 5988 65727 44934 543 973553 3 479826 26223 3758 32 256732 738 287639 33 887977 7742 2386 34 654335 44689 2386 35 596 36 3666
Sheet P2a Fishery by Operational Unit Code: DPS99S. Page 3 / 4 Data source* EU Data Collection Framework OpUnit 3* ITA 99 F 3 34 - DPS Time series Year* 27 28 29 Catch 297 227 777 Minimum size Average size Lc Maximum size Fleet Year Catch Minimum size Average size Lc Maximum size Fleet Selectivity L25 5.5 L5 7 L75 8.5 Selection factor.42 Remarks 2 Structure by size or age LC 29 Male Female 28_F 28_M 27_F 27_M 2 882 3 4 4 72448 553 98253 27932 33 5 62228 34748 62834 7374 4793 6 462 73 65425 277 89548 7 36796 22497 36422 95376 84863 346 8 24964 243497 238656 332762 86923 294929 9 285642 22442 3988 428937 2535763 655898 2 45345 4687522 6697499 9977 378557 97774 2 79773 6484 23662 445 49987 894374 22 7253768 953675 384955 43483 5489 2394399 23 849346 2459466 73276 833526 689544 27788357 24 6485632 545839 89395 56424 4428865 2995397 25 29233 8396795 78469 42455 4729978 34454833 26 574239 56634 5694226 26788 336679 26496574 27 77345 36865 3533979 373466 2828533 58469
Sheet P2a (Page 3 / 4-2 sheet) 28 339655 32 848576 854 4726328 67974 29 9887 874446 38963 72324 72796 849539 3 256 648343 99883 56997 79262 839485 3 34442 479552 895794 4286 34456 248943 32 52 29225 632683 959 758 8944 33 5376 2794 334483 7443 4969229 34 562845 249782 23374 35 56485 93826 62332 36 3955 3739 39248 37 6846 367448 38 55986 74725 39 3278 9996 4 47429 4
Sheet P2a Fishery by Operational Unit Code: DPS99S. Page 4 / 4 Data source* Tunisian National Data Collection Programme OpUnit 4* TUN 99 F 3 34 - DPS Time series Year* 27 28 29 Catch 3 992 55 Minimum size 3 3 3 Average size Lc 24.89 26.8 25.56 Maximum size 42 42 42 Fleet F-trawl F-trawl F-trawl Year Catch Minimum size Average size Lc Maximum size Fleet Selectivity L25 L5 L75 Selection factor.4 Remarks 2 Structure by size or age LC 29 Male Female 28_F 28_M 27_F 27_M 3 358 32229 29937 4 2428 28976 3539 598 7782 3624 5 89585 579 24 58292 46797 723282 6 922257 657247 65279 26753 6439 88234 7 24829 67944 576372 39283 935826 36956 8 68853 72674 743755 67329 27524 95594 9 28298 22946 85756 73228 29446 876868 2 253356 24892 2689 934897 2736 296669 2 5247474 3532375 93874 24585 39233 48768 22 76339 377755 274724 383447 3892 67863 23 968438 4744672 23672 48789 369243 766242 24 863458 6442 3345677 54999 4739873 7264852 25 66424 49872 52622 3353 673853 4389338 26 494788 339734 746935 836768 898575 276294 27 43427 85246 928667 455446 994378 564246 28 65772 496879 929225 9826 942788 96725 29 6795 99655 6659 58849 5477265 53646
Sheet P2a (Page 4 / 4-2 sheet) 3 25486 82525 5772593 483425 4829296 47947 3 22955 5993883 48475 459546 3776 359436 32 3242 4286823 4958 735 29836 77375 33 2385 293329 2384787 9824 5962 649 34 8525 2685 278749 5252 674692 9446 35 433 28994 9787 5546 499 8756 36 968687 65347 34864 37 462 5277 367247 5859 692826 259 38 462 324867 9835 54235 43448 259 39 2385 222464 98828 4 79747 3926 36393 4 69 42 5843 4425 526
Sheet P2b Fishery by Operational Unit Code: DPS99S. Page / Data source* EC 967 / 26 OpUnit * MLT 99 E 3 34 - DPS Regulations in force and degree of observance of regulations At present there are no regulations in force specifically targeting giant deepwater rose shrimp. However, in order to limit the over-capacity of fishing fleet, Maltese fishing licenses had been fixed at a total of 6 trawlers since 2. Eight new licences were however issued in 28, a move made possible under EU law by the reduction of the capacities of other Maltese fishing fleets. Moreover, the Maltese Islands are surrounded by a 25 nautical miles (nm) fisheries management zone, where fishing effort and capacity are being managed by limiting vessel sizes, as well as total vessel engine powers (EC 83/4; EC 967/6). Trawling is allowed within this designated conservation area, however only by vessels not exceeding an overall length of 24m and only within designated areas. Such vessels fishing in the management zone hold a special fishing permit in accordance with Article 7 of Regulation (EC) No 627/94, and are included in a list containing their external marking and vessel's Community fleet register number (CFR) to be provided to the Commission annually by the Member States concerned. Moreover, the overall capacity of the trawlers allowed to fish in the 25nm zone can not exceed 4 8 kw, and the total fishing effort of all vessels is not allowed to exceed an overall engine power and tonnage of 83 kw and 4 35 GT respectively. Accompanying species The fishing capacity of any single vessel with a license to operate at less than 2m depth can not exceed 85 kw. In addition, the use of all trawl nets within.5nm of the coast is prohibited according to EC regulation 967 / 26, although again a transitional derogation is at present in place until 2. In terms of technical measures, the new regulation EC 967 of 2 December 26 fixed a minimum harvest size of 2mm and a minimum mesh size of 4 mm for bottom trawling of EU fishing vessels (i.e. Italian and Maltese trawlers in the Central Mediterranean). Mesh size had to be modified to square 4 mm or diamond 5 mm in July 28, and derogations are no longer possible since June 2. Deepwater rose shrimp are frequently caught together with Norway lobster (Nephrops norvegicus), large sized giant red shrimp (Aristaeomorpha foliacea), the more rare violet shrimp (Aristeus antennatus), the scorpionfish Helicolenus dactylopterus, grater forkbeard (Phicys blennioides), the flat fish Lepidorombus boscii, the squid Todarodes sagittaus, as well as small hake (Merluccius merluccius).
Sheet P2b Fishery by Operational Unit Code: DPS99S. Page 2 / Data source* OpUnit 2* ITA 99 E 3 34 - DPS Regulations in force and degree of observance of regulations At present there are no formal management objectives for giant red shrimp fisheries in the Strait of Sicily. In terms of technical measures, the new regulation EC 967 of 2 December 26 fixed a minimum mesh size of 4 mm for bottom trawling of EU fishing vessels (Italian and Maltese trawlers). Mesh size had to be modified to square 4 mm or diamond 5 mm in July 28, however derogations are possible up to 2. No minimum landing sizes have been established for this species (EC 967/6). A medium term management plan for 28-23 has been agreed for Italian trawlers operating in the GSA 5 and 6. This Italian Management Fishery Plans (IFMP) is based on : a fleet reduction of 25% of the current capacity obtained in two steps. The first (2.5%) from 28 to 2, and the second (2.5%) from 2 to 23; a trawling ban of 45 days per year between January and March (targeted to deep water pink shrimp fishery which is the main commercial species in the GSA 5 and 6); changing the mesh opening in the cod-end from the 4 mm to 5 mm (diamond) from 2; Accompanying species Although designed mainly for deep water pink shrimps, the adoption of the management measures of the IFMP are also expected to improve the stock status of giant red shrimp in the area. Deepwater rose shrimp are frequently caught together with Norway lobster (Nephrops norvegicus), large sized giant red shrimp (Aristaeomorpha foliacea), the more rare violet shrimp (Aristeus antennatus), the scorpionfish Helicolenus dactylopterus, grater forkbeard (Phicys blennioides), the flat fish Lepidorombus boscii, the squid Todarodes sagittaus, as well as small hake (Merluccius merluccius).
Sheet P2b Fishery by Operational Unit Code: DPS99S. Page 3 / Data source* OpUnit 3* ITA 99 F 3 34 - DPS Regulations in force and degree of observance of regulations At present there are no formal management objectives for giant red shrimp fisheries in the Strait of Sicily. In terms of technical measures, the new regulation EC 967 of 2 December 26 fixed a minimum mesh size of 4 mm for bottom trawling of EU fishing vessels (Italian and Maltese trawlers). Mesh size had to be modified to square 4 mm or diamond 5 mm in July 28, however derogations are possible up to 2. No minimum landing sizes have been established for this species (EC 967/6). A medium term management plan for 28-23 has been agreed for Italian trawlers operating in the GSA 5 and 6. This Italian Management Fishery Plans (IFMP) is based on : a fleet reduction of 25% of the current capacity obtained in two steps. The first (2.5%) from 28 to 2, and the second (2.5%) from 2 to 23; a trawling ban of 45 days per year between January and March (targeted to deep water pink shrimp fishery which is the main commercial species in the GSA 5 and 6); changing the mesh opening in the cod-end from the 4 mm to 5 mm (diamond) from 2; Accompanying species Although designed mainly for deep water pink shrimps, the adoption of the management measures of the IFMP are also expected to improve the stock status of giant red shrimp in the area. Deepwater rose shrimp are frequently caught together with Norway lobster (Nephrops norvegicus), large sized giant red shrimp (Aristaeomorpha foliacea), the more rare violet shrimp (Aristeus antennatus), the scorpionfish Helicolenus dactylopterus, grater forkbeard (Phicys blennioides), the flat fish Lepidorombus boscii, the squid Todarodes sagittaus, as well as small hake (Merluccius merluccius).
Sheet P2b Fishery by Operational Unit Code: DPS99S. Page 4 / Data source* OpUnit 4* TUN 99 F 3 34 - DPS Regulations in force and degree of observance of regulations Actually there are no specific regulations for pink shrimp fisheries in the Tunisian waters. However, there is a trawling ban in areas comprised under 3 miles from the coast and/or less 5m depth. In terms of technical measures, the minimum mesh size in cod end of trawler should not less than 4 mm for bottom trawling in Tunisian waters. Accompanying species Deepwater rose shrimp in Tunisia are frequently caught together with hake (Merluccius merluccius), red Pandora (Pagellus bogaraveo), common Pandora (Pagellus erythriuns), monkfish (Lophius piscatorius), mackerel (Trachurus spp.), Norway lobster (Nephrops norvegicus) and more rarely giant red shrimp (Aristaeomorpha foliacea) and violet shrimp (Aristeus antennatus).
Sheet A Indirect methods: VPA, LCA Code: DPS99S. Sex* F+M 27 Page / 4 Time series Analysis # * LCA Data (mark with X) Size x Age Model (mark with X) Cohorts Pseudocohorts x Equation used # of gears VPA 3 Tunig method Software None VIT 4 win F terminal.5 in females and.2 in males Population results (please state units) Sizes Minimum Average Maximum 4 Critical Ages.237 3.9 Recruitment Average population Virgin population Turnover Amount 357 878 Biomass mm year millions t Average mortality Gear Total Italian 2-24 Italian >24 Tunisian F.97.26.42.3 F 2 Z (F and F2 represent different possible calculations. Please state them) Comments 332 Fishing mortality obtained as (Catch F + Catch M)/ VPA mean number F + VPA mean number M) by size F is expressed as arithmetic values of F on overal size of catch
Sheet A Indirect methods: VPA, LCA Code: DPS99S. Sex* F+M 28 Page 2 / 4 Time series Analysis # * LCA Data (mark with X) Size X Age Model (mark with X) Cohorts Pseudocohorts X Equation used # of gears VPA 3 Tunig method Software None Vit4win F terminal.5 in females and.2 in males Population results (please state units) Minimum Average Maximum Critical Sizes 4 Ages.44 3.9 Amount Recruitment 273 Average population 533 Virgin population Turnover Biomass mm year millions t Average mortality F Total.97 Italian 2-24 Italian >24.32.36 Gear Tunisian.29 F 2 Z (F and F2 represent different possible calculations. Please state them) Comments 332 Fishing mortality obtained as (Catch F + Catch M)/ VPA mean number F + VPA mean number M) by size F is expressed as arithmetic values of F on overal size of catch
Sheet A Indirect methods: VPA, LCA Code: DPS99S. Sex* F+M 29 Page 3 / 4 Time series Analysis # * LCA Data (mark with X) Size x Age Model (mark with X) Cohorts Pseudocohorts x Equation used # of gears VPA 4 Tunig method Software None Vit4win F terminal.5 in females and.2 in males Population results (please state units) Sizes Ages Minimum.237 Average Maximum 4 3.9 Critical Recruitment Average population Virgin population Turnover Amount 3528 9 Biomass mm year million t Average mortality Total Italian 2-24 F.34.56 Gear Italian >24 Tunisian.3.47 Maltese.2 F 2 Z (F and F2 represent different possible calculations. Please state them) Comments 332 Fishing mortality obtained as (Catch F + Catch M)/ VPA mean number F + VPA mean number M) by size F is expressed as arithmetic values of F on overal size of catch
Sheet A Indirect methods: VPA, LCA Code: DPS99S. Sex* F+M mean 3y Page 4 / 4 Time series Analysis # * LCA Data (mark with X) Size X Age Model (mark with X) Cohorts Pseudocohorts x Equation used # of gears LCA 4 Tunig method Software no ANALEN F terminal.8 Population results (please state units) Minimum Average Maximum Critical Sizes 8 4.35 36 8.5 Ages Recruitment Average population Virgin population Turnover Amount Biomass 3326 34 9 mm million t Average mortality Total F.25 Gear Italian 2-24 Italian >24 Tunisian.42.42.45 Maltese.3 F 2 Z 2.365 (F and F2 represent different possible calculations. Please state them) Comments 335 Fishing mortality by size obtained as average of F females and F males weighted by Sex Ratio in catch F is expressed as arithmetic values of F within 38 mm CL
Sheet A2 Indirect methods: data Code: DPS99S. Sex* F & M sep. Gear* Trawl Analysis # * VPA Data source LFD Data 7 6 5 4 3 2 N Individuals Small Boat Italy Female Ita_29 N=53792 Male Ita_29 N=32757538 Female Ita_28 N=24954686 Male Ita_28 N=273834 Female Ita_27 N=378395834 Male Ita_27 5 2 25 3 35 N=36857285 4 CL (mm) Big Boat Italy Female Ita_29 N=3882672 N Individuals 4 3 2 Male Ita_29 N=4876654 Female Ita_28 N=78765475 Male Ita_28 N=7789372 Female Ita_27 N=964 5 2 25 3 35 4 45 CL (mm) Male Ita_27 N=27867424 Big Boat Tunisia Female Tun_29 N=2943332 2 Male Tun_29 N=59298 N Individuals 5 5 Female Tun_28 N=756976 Male Tun_28 N=2995824 Female Tun_27 N=83628 Male Tun_27 5 2 25 3 35 4 N=4665273 45 CL (mm) N Individuals 25 2 5 5 Female MLT N=2883 Male MLT N=6989 5 2 25 3 35 4 CL (mm) 25 2 5 5
Sheet A3 Indirect methods: VPA results Sex* F&M Gear* Trawl 27 Analysis #* Code: DPS99S. Page / 4 LCA VIT Population in figures 8 Population at sea - 27 Number at sea 6 4 2 2 4 6 8 2 22 24 CL(mm) 26 28 3 32 34 36 38 Population in biomass Biomas ss at sea (g) 3 25 2 5 5 Population at sea - 27 2 4 6 8 2 22 24 CL(mm) 26 28 3 32 34 36 38 Fishing mortality rates 2.5 2 Fishing mortalities by metiers - combined sex - 27.5.5 38 36 34 32 3 28 26 24 22 2 8 6 4 2 total (F=.97) Italian 2-24 (F=.26) Italian >24(F=.42) Tunisian (F=.3)
Sheet A3 Indirect methods: VPA results Sex* F&M Gear* Trawl 28 Analysis #* Code: DPS99S. Page 2 / 4 LCA VIT Population in figures Population at sea - 28 8 Number at sea 6 4 2 2 4 6 8 2 22 24 CL (mm) 26 28 3 32 34 36 38 Population in biomass Biomas ss at sea (g) 25 2 5 5 Population at sea - 28 2 4 6 8 2 22 24 CL (mm) 26 28 3 32 34 36 38 Fishing mortality rates 2. Fishing mortalities by metiers - combined sex - 28.5..5. 38 36 34 32 3 28 26 24 22 2 8 6 4 2 Total (F=.97) Italian 2-24 (F=.32) Italian >24(F=.36) Tunisian (F=.29)
Sheet A3 Indirect methods: VPA results Sex* F&M Gear* Trawl 29 Analysis #* Code: DPS99S. Page 3 / 4 LCA VIT Population in figures Population at sea - 29 8 Number at sea 6 4 2 2 4 6 8 2 22 24 CL (mm) 26 28 3 32 34 36 38 Population in biomass Biomas ss at sea (g) 3 25 2 5 5 Population at sea - 29 2 4 6 8 2 22 24 CL (mm) 26 28 3 32 34 36 38 Fishing mortality rates 3. 2.5 2..5..5. Fishing mortalities by metiers - combined sex - 29..8.6.4.2 38 36 34 32 3 28 26 24 22 2 8 6 4 2 total (F=.34) Italian 2-24 (F=.56) Italian >24 (F=.3) Tunisian (F=.47) Maltese (F=.2)
Sheet A3 Indirect methods: VPA results Sex* F&M Gear* Trawl Analysis #* Code: DPS99S. Page 4 / 4 LCA ANALEN Population in figures Survivors Number*^ 5 4 3 2 N: M=,5 +,2 N: M=,8 (, ) 8 8 28 38 Length (Lc in mm) Population in biomass 8 6 ^6 B* 4 2 2 3 4 Length (Lc in mm) Fishing mortality rates 3 2.5 2.5.5 INDTUNIS INDITALY ARTITALY F: M=,5 +,2 ARTMALTA 8 8 28 38 Length (cm).5..5
Sheet Y Indirect methods: Y/R Sex F+M Analysis # Code: DPS99S. LCA # of gears trawl Software VIT4win Parameters used Vector F Vector M Vector N Model characteristics Values of VPA and Y/R analyses were estimated by sex and years. For each year, results were averaged by a sex ratio (.57 females and o.43 males) weighed mean. Results Total Gear Trawl MAL Trawl ITA 2_24 Trawl ITA>24 Trawl TUN Current YR 2.44-3.3.6 -.6.453 -.88.584 -.68.44 -.57 Maximum Y/R NC - 3.8 NC NC NC -.63 NC -.45 Y/R. 2.33-3.6.5 -.6.23 -.74.65 -.68.468 -.63 F max.235 -.52 F..9 -.82 Current B/R 2.35-2.74 Maximum B/R NC - 2.24 B/R. 2.745 - NC Current SSB/R.49 NC on left VIT SSB/R..86 - NC on right ANALEN SSB/R virgin 5.59 - NC Comments Year Factor F Y/R B/R SSB Y/R Italian 2-24 Y/R Italian >24 Y/R Tunisian Y/R Maltese... 6.46 5.5... NA 27.79.76 2.2 3.3 2.7.94.77.42 NA.. 2.25 2.55.74.3.72.4 NA... 6.68 5.77... NA 28.94.95 2.46 2.72.89.29.78.38 NA..2 2.5 2.52.7.36.79.36 NA... 6.46 5.5.... 29.73.98 2.4 2.76.85.38.52.5...35 2.57 2.24.37.6.52.44.... 6.54 5.59.... MEAN.82.9 2.33 2.84.97.2.69.44...3 2.45 2.44.6.37.67.4.... 6.46 5.5.... MEDIAN.79.95 2.4 2.76.89.29.77.42...2 2.5 2.52.7.36.72.4.
Sheet Y (page 2) Comments 3.5 3 2.5 Y/R (g) 2.5.5 Y/R Total Y/R (g) ITA_Big Boat Y/R (g) MLT Y/R (g) ITA_Small Boat Y/R (g) TUN SSB/R (g) 8 7 6 5 SSB/R (g) 4 3 2 Y/R (g) 2.5 2.5.5 Y/R Total Y/R ITA Big Boat Y/R MLT Y/R ITA Small Boat Y/R TUN SSB/R (g) 4.5 4 3.5 3 2.5 2.5.5 SSB/R (g).25.5.75.25.5.75 2 Effort level.25.5.75.25.5.75 2 Effort level 3.5 3 2.5 Y/R (g) 2.5.5 Y/R Total Y/R (g) ITA_Small Boat Y/R (g) ITA_Big Boat Y/R (g) Tun SSB/R (g) 2.25.5.75.25.5.75 2 Effort level 8 7 6 5 4 3 SSB/R (g) 2.5 2.5 Y/R (g).5 Y/R Total Y/R (g) ITA_Small Boat Y/R (g) ITA_Big Boat Y/R (g) Tun SSB/R (g) 5 4.5 4 3.5 3 2.5 2 SSB/R (g).5.5.25.5.75.25.5.75 2 Effort level Y/R (gr) 3.5 3 2.5 2.5.5 Y/R (g) Total Y/R (g) ITA Small Boat Y/R (g) ITA Big Boat Y/R (g) Tun SSB/R (g).25.5.75.25.5.75 2 Effort Level 8 7 6 5 4 3 2 SSB/R (gr) Y/R (gr) 2.8.6.4.2.8.6.4.2 Y/R (g) Total Y/R (g) Ita Small Boat Y/R (g) Ita Big Boat 4.5 4 3.5 3 2.5 2.5.5.25.5.75.25.5.75 2 Effort Level SSB/R (gr)
Sheet other Other assessment methods 559 Code: DPS99S. Page / 3 Y and B per recruit of females estimated by Yield package (Branch, T. A. et, al., 2). All the linear parameters were converted in TL (cm). Conversions were made by using the relationship reported by Crosnier et al.,(97): TL(mm)= 3,646+4,436 CL(mm).Y and B per recruit estimated only Female. Probability distribution of Fmax, F. and FSPR.3 were estimated by 2 simulations. Incertidute was added to all parameters as a CV of 2%..2.4 Parameters Y/R Biomass SSB Y/R Biomass SSB Y/R Biomass SSB 'oooooooooo' 2.36 2.44.66 2.36 2.44.66 2.36 2.44.66 'o-ooo-oooo' 2.37 2.7.84 2.37 3.4 2.6 2.38 4.4 2.73 'o-ooo+oooo'.77 2.48.67.7 2.48.63.23 2.9.29 'o+ooo-oooo' 2.94 2.39.64 3.47 2.33.6 4.44 2.2.54 'o+ooo+oooo' 2.36 2.23.52 2.36 2.5.4 2.35.76.2 Changing M and k has a pronounced effect on Y/R when the variation is in the opposite direction; while B/R and SSB/R are strongly affected when the change is in the same direction
Sheet other Other assessment methods 2 Code: DPS99S. Page 2 / 3 asdfasd Y/R /g) 7 6 5 4 3 2 Y/R (g) 2.5% Y/R (g) mean Y/R (g) 97% SSB/R (g) 2.5% SSB/R (g) mean SSB/R (g) 97% 3 25 2 5 5 SSB/R (g).25.5.75.25.5.75 2 2.25 2.5 F 8 Median F max=.89 6 Median F.=.88 Median F ssb.3=.33 4 Probability % 2 8 6 4 2.5.5 2 2.5 3 3.5 4 Fishing mortality (F)
Sheet other Other assessment methods 2 Code: DPS99S. Page 3 / 3 Transient analyses with Lc=6 mm CL, Fc=.2 and F.=.9 3 5 2.8 2.6 45 2.4 4 Fishing mortality (F) 2.2 2.8.6.4.2.8 35 3 25 2 5 Yield or SSB in tons.6.4.2 F Yield SSB 5 22 22 29 28 27 26 25 24 23 22 2 2 29 28 27 26 25 24 23 22 Transient analyses with Lc=2 mm CL, Fc=.2 and F.=.9 3 5 Fishing mortality (F) 2.8 2.6 2.4 2.2 2.8.6.4.2.8.6.4.2 F Yield SSB 45 4 35 3 25 2 5 5 Yield or SSB in tons 22 22 29 28 27 26 25 24 23 22 2 2 29 28 27 26 25 24 23 22
Sheet other Other assessment methods 5 2 Y, M=,5 +,2 Y, M=,8 (, ) Code: DPS99S. Page 4 / 3 2 2-8 6 4-4 2-7.5.5 2 Effort multiplication -2 Cha ange in long term yield (%) 8 4-4 INDTUNIS ARTITALY ARTMALTA INDITALY -8.4.8.2.6 2 Effort multiplication Analen
Sheet D Diagnosis Indicators and reference points Code: DPS99S. Criterion B SSB F Y CPUE Current value Units Reference Point 2:35 g 2.745.49 g.864.3.9 2.466 g 2.33 Trend Comments All biomass and yield values are per recruit A reduction of 2% is adviced to reach the F. target reference point (VIT analyses) Stock Status* Use one (or both) of the following two systems for the stock assessment status description Unidimensional FALSE FALSE FALSE FALSE TRUE FALSE? - (or blank) Not known or uncertain. Not much information is available to make a judgment; U - Underexploited, undeveloped or new fishery. Believed to have a significant potential for expansion in total production; M - Moderately exploited, exploited with a low level of fishing effort. Believed to have some limited potential for expansion in total production; F - Fully exploited. The fishery is operating at or close to an optimal yield level, with no expected room for further expansion; O - Overexploited. The fishery is being exploited at above a level which is believed to be sustainable in the long term, with no potential room for further expansion and a higher risk of stock depletion/collapse; D - Depleted. Catches are well below historical levels, irrespective of the amount of fishing effort exerted; FALSE R - Recovering. Catches are again increasing after having been depleted or a collapse from a previous; Bidimensional FALSE FALSE FALSE FALSE TRUE FALSE Exploitation rate No or low fishing Moderate fishing High fishing mortality Uncertain / Not assessed TRUE FALSE Stock abundance Virgin or high abundance FALSE Intermediate abundance Low abundance Depleted Uncertain / Not assessed
Sheet D (page 2) Comments 3843 NB. NB. Although the stock is considered overfished taking into account F. as a reference point, no risk of depletion was recognised by the working group.
Sheet Z Objectives and recommendations Code: DPS99S. Management advice and recommendations* 862 Considering F. as target reference point (TRP), the stock appears overexploited. In order to reach this TRP the current F should be reduced by around 2%. A moderate reduction (2%) of current F would not, in the long-term, lead to a sensitive change in yield. However, this reduction would improve significantly the spawning stock biomass (SSB). A reduction in F could be achieved by reducing fishing effort through either a change in fishing capacity or a change in fishing activity. Available information suggests to reduce the fishing mortality caused mainly the trawlers 2-24m LOA, in order to protect the smaller size classes of pink shrimp which are the target of this fleet. In addition the selection pattern of the fishery should be improved. A moderate increase in the minimum length limit in catches would not have a substantial impact on the long term catches if fishing effort is kept unchanged. If the minimum length limit is increased by 2%, the long term catch would be increased only by around %, but spawning stock biomass will be increased significantly. The gain in SSB for an increase by 2 and 5% will be respectively 38 and 49%. With regards to the impacts on the separate fleet components, the moderate increase (2%) in minimum length limit leads to a gain of 6% in sustainable yield for the fleet of large trawlers, while the fleet of small trawlers would suffer long-term losses (around 7%). The working group was informed that the Italian government is adopting a management plan in which a reduction of trawling capacity of 25% is planned within 23. It is worth to note that an improvement of fishing pattern, with some effects on the current stock status, should already be expected due to the implementation of the new mesh size after June 2 in the Maltese and Italian trawl fisheries (based on EC 967/26). Finally, a protection of key nursery areas in the Strait of Sicily is recommended in order to improve the status of this fishery. Stable nurseries of this species have been identified on the Adventure and Malta Banks in the Strait of Sicily by Fortibuoni et al. (2).
Advice for scientific research* 3526 In order to make the assessment more robust, a trawl survey covering the whole area (GSA 2; 3; 4; 5 and 6) should be planned. This source of information should allow an investigation of the spatial structure of species in the area, including the position of main nursery and spawning areas of deepwater rose shrimp. Furthermore data on spatial distribution of trawling effort should be collected and made available for stock assessment and management purposes.
Sheet C Comments Code: DPS99S. Page / Comments* 2734 Several problems were encountered when completing the GFCM stock assessment form: - On the contacts sheet the old SCSA coordinator is listed (Constantina Karlou-Riga), this needs to be updated - A maximum of 3 GSAs can be added to the cover sheet, this number needs to be increased. For instance in the present assessment 5 GSAs were covered - On form P, general information for the fishery can only be provided for one year. For this assessment data was assessed for 3 years, but only data for the most recent year could be provided - On sheet Y, additional space should be added to report the results of indirect methods. For instance in this assessment two indirect methods were used (VIT and ANALEN) but there was no space to report the results of the two separate analyses. - The definition of an overexploited stock needs to be rewritten in sheet D, since it is possible to have for instance an economically overexploited stock where there is however no imminent risk of depletion or collapse - A form suitable for use with Apple-MAC computers should be made available since participants using MAC computers were unable to fill in the forms. An improvement of the forms would improve future presentation of stock assessment results.
Abstract for SCSA reporting Authors S. Ben Meriem, F. Fiorentino, V. Gancitano, L. Knittweis, O. Jarboui, L. Ceriola, E. Arneri Year 2 Species Scientific name Parapenaeus longirostris - DPS Source: GFCM Priority Species Source: - Source: - Geographical Sub-Area 6 - South of Sicily, 5 - Malta Island, 2 - Northern Tunisia Fisheries (brief description of the fishery)* 253 Sicilian trawlers between 2-24m LOA which target deep water pink shrimp are based in seven harbours along the southern coasts of Sicily. These trawlers (about 5 boats in 29) operate mainly on a short-distance trawl fishery basis, with trips from to 2 days at sea, fishing on outer shelf and upper slope. The distant trawlers of Mazara del Vallo (about 4 boats in 29) represent the main commercial fleet of trawlers in the area, and are one of the most important fleets in the Mediterranean. In contrast to the other Sicilian fleets, the large trawlers of the Mazara fleet (LOA>24m) are employed on long fishing trips (3 4 weeks) in offshore waters. These vessels thus operate in both national and international waters in the Strait of Sicily. In the Maltese Islands small vessels measuring 2-24m in length target pink shrimp at depths of about 6m, with fishing grounds located to the north / north-west of Gozo, as well as to the west / south-west of Malta. Catches are primarily destined for the local market. Tunisian vessels target pink shrimp primarily in Northern Tunisia, with 9% of the country s total P. longirostris catches originating here. The great majority of these catches are landed in the town of Bizerte. ssessment Forms
Source of management advice* (brief description of material -data- and methods used for the assessment) 2 Data was derived both from indirect (fisheries monitoring) sources. Stock status was assessed by using a Yield and Spawning Stock Biomass per Recruit analysis with the VIT, ANALEN Yield packages. Analyses were based length frequency distributions by sexes. Current F was assessed using a steady state VPA with VIT by length on LFD of 27, 28 and 29 raised to the total landings. VPA and Y/R values by sex and year were combined to obtain a single values for both the sexes. Stock Status* O - Overexploited. The fishery is being exploited at above a level which is believed to be sustainable in the long term, with no potential room for further expansion and a higher risk of stock depletion/collapse; Exploitation rate High fishing mortality Comments Stock abundance Intermediate abundance NB. Although the stock is considered overfished taking into account F. as a reference point, no risk of depletion was recognised by the working group. ssessment Forms
Management advice and recommendations* Considering F. as target reference point (TRP), the stock appears overexploited. In order to reach this TRP the current F should be reduced by around 2%. A moderate reduction (2%) of current F would not, in the long-term, lead to a sensitive change in yield. However, this reduction would improve significantly the spawning stock biomass (SSB). A reduction in F could be achieved by reducing fishing effort through either a change in fishing capacity or a change in fishing activity. Available information suggests to reduce the fishing mortality caused mainly the trawlers 2-24m LOA, in order to protect the smaller size classes of pink shrimp which are the target of this fleet. In addition the selection pattern of the fishery should be improved. A moderate increase in the minimum length limit in catches would not have a substantial impact on the long term catches if fishing effort is kept unchanged. If the minimum length limit is increased by 2%, the long term catch would be increased only by around %, but spawning stock biomass will be increased significantly. The gain in SSB for an increase by 2 and 5% will be respectively 38 and 49%. With regards to the impacts on the separate fleet components, the moderate increase (2%) in minimum length limit leads to a gain of 6% in sustainable yield for the fleet of large trawlers, while the fleet of small trawlers would suffer long-term losses (around 7%). The working group was informed that the Italian government is adopting a management plan in which a reduction of trawling capacity of 25% is planned within 23. It is worth to note that an improvement of fishing pattern, with some effects on the current stock status, should already be expected due to the implementation of the new mesh size after June 2 in the Maltese and Italian trawl fisheries (based on EC 967/26). Finally, a protection of key nursery areas in the Strait of Sicily is recommended in order to improve the status of this fishery. Stable nurseries of this species have been identified on the Adventure and Malta Banks in the Strait of Sicily by Fortibuoni et al. (2). ssessment Forms
Advice for scientific research* In order to make the assessment more robust, a trawl survey covering the whole area (GSA 2; 3; 4; 5 and 6) should be planned. This source of information should allow an investigation of the spatial structure of species in the area, including the position of main nursery and spawning areas of deepwater rose shrimp. Furthermore data on spatial distribution of trawling effort should be collected and made available for stock assessment and management purposes. ssessment Forms