Report on the recovery of historical data of bluefin tuna catches in the Portuguese tuna traps. João Gil Pereira

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1 Report on the recovery of historical data of bluefin tuna catches in the Portuguese tuna traps by João Gil Pereira Universidade dos Açores Horta, Portugal Summary Historical data of the bluefin tuna catches in the Portuguese traps, was recovered under the GBYP Data Recovery Plan on Historical bluefin tuna. The data recovered includes the Task-I and Task-II data of the Portuguese trap fishery on BFT between 1896 and Complementary information recovered, included daily catches for several traps, in number of fish and corresponding weights for a large number of years, between 1876 and Information concerning Portuguese imports of large bluefin tuna from Moroccan traps, from 1948 to 1965 includes the total number of fish imported and the corresponding weights. Introduction In April 2011, a contract has been signed between the University of Azores and ICCAT, under the GBYP Data Recovery Plan on Historical bluefin tuna (Call for Tenders, Circular n. 320/2011), in order to support the recovery of historical data of the bluefin tuna catches in the Portuguese traps. The work has been developed according to the main objectives of the contract, i.e., the recovery of the Task-I and Task-II data of the Portuguese trap fishery on BFT between 1896 and This objective was fully achieved and the detailed data collected was transmitted to ICCAT. A preliminary presentation of the data recovered was presented at the Bluefin tuna trap symposium in Tangier, Morocco, in May During the data recovery, information was also found concerning some Portuguese imports of large bluefin tuna from Moroccan traps. This information from1948 to 1965 includes the total number of fish imported and the corresponding weights. The recovery of this information was 1

2 included in the contract as a secondary objective, was also presented at the Bluefin tuna trap symposium in Tangier, Morocco, in May 2011, and is presented in annex During the research done in some historical archives, more detailed and complementary information was found and recovered. This complementary information recovered, included daily catches for several traps, in number of fish and corresponding weights for a large number of years, between 1876 and Recently (August, 2011), new detailed information was found and recovered in some municipal archives. This new information is presently been processed to be transmitted to ICCAT. Detailed description of the recovered datasets Information concerning the historical Portuguese tuna trap catches is now available for a large number of years, with different kinds of detail. The most detailed data concerns the period from 1896 to For this period, the information was obtained by trap, month and/or 2 month periods: May/June; July/August, corresponding to the 2 fishing seasons, the first called direito for the fish entering the Mediterranean and the second revés for the fish going out of the Mediterranean.). The catches of bluefin tuna were recorded in number and by commercial category, since the bluefin caught by the Portuguese traps were commonly recorded in number of fish, qualified in 4 commercial categories ( atum : > 90 kg; atuarro : from 50 to 89 kg; albacore : from 30 to 49 kg; cachorreta : <30 kg). A fifth category, the cachorretitas, used for fish less than 10 kg was also found in some of the detailed records from some traps. Some of the traps did not include in their official catch declarations the smaller sizes, the albacore : from 30 to 49 kg; and cachorreta : <30 kg. However, in the cases where the detailed records are available, information on the catches of these small fish was also recovered and it s now available for some traps/years. The commercial categories used in Portugal for bluefin and their respective weights and sizes, are given in table 1. Portugal - Commercial Categories (BFT) CCatID CCatName Description MeanWprev(kg) CC1 Small (< 10kg) Cachorretitas 5 CC2 Small (< 30kg) Cachorretas ( < 1.00 m) 20 CC3 Medium (30>= X < 50 kg) Albacora (1.00 m>= X < 1.30 m) 40 CC4 Medium (50>= X < 90 kg) Atuarros (1.30 m>= X < 1.90 m) 70 CC5 Large (>= 90 kg) Atum > 1.90 m 150 Table 1. Commercial categories for bluefin tuna used in the Portuguese statistics In the data recovered for some traps/years, different values were found for the total catch of bluefin or for the catches by commercial category. This can be explained by the fact that in some traps, only the large bluefin were recorded or when reporting the total annual catch referred only to large bluefin (atum category), the other size categories were converted to atum (2 atuarros, 4 2

3 albacoras or 8 cachorretas corresponded to 1 atum). However, since we had the possibility of consulting records with several levels of detail, this situation has been corrected in many cases. For some years and traps, it was also possible to recover information on daily catches by commercial category, including the information on the respective weights. This information is available for 4 traps from 1962 to 1967 and from 1958 to 1972 for 1 trap. (table 4). This detailed records allowed the estimation of daily average weights for the different size categories of bluefin tuna caught in south Portugal, from 1958 to The recovered information is presented in several files, containing the following information: 1. Catches in number of fish by commercial categories, by trap, year and month. Includes 11 traps and 1042 records 2. Catches in number of fish by commercial categories, by trap and year. Includes 24 traps and 699 records 3. Catches in number of fish by commercial categories, by trap, year and season (bimonthly). Includes 24 traps and 1034 records 4. Estimated total catch of bluefin tuna, in weight, by commercial categories from 1896 to Daily catches in number of fish and respective weight. Includes 5 traps and 4878 records. 6. All the detailed information collected was merged in a single excel file and transmitted to ICCAT GBYP. Type of support The information was found in different locations, including public and private libraries, historical archives, historical municipal archives and some private collections. Some of the public libraries/archives where information was collected are listed below: Instituto Nacional de Estatística Biblioteca, Direcção Geral das Pescas e Aquicultura Arquivo Histórico da Direcção Geral das Pescas Arquivo do Grémio dos Armadores de Atum (GAPATUM) Arquivo Distrital de Faro Arquivo Municipal de Tavira Arquivos da Companhia de Pescarias do Algarve, Faro Bibliotecas Municipais da Horta, Ponta Delgada e Tavira Given its historical content (centenary data in its majority) and its dispersion across the various data sources, a considerable travelling was necessary to consult and collect the information. For some years and traps, the catch information of the different sources is contradictory, which required a further validation process. The sources containing the information are of variable quality (mostly in paper) and were found throughout many publications and documents of different types, including statistical bulletins, daily traps records, financial reports of the traps societies and other historical documents. The detailed records from the traps are mostly handwritten with different levels of quality. 3

4 Due to the difficulty in the interpretation of the handwritten information and the amount of paper records found, most of the archives were photographed and processed later. A short summary of the recovered information is presented in the figures and tables bellow. Trap Period Number of years Abóbora ; Barril (3 Irmãos) Beliche 1905; 1 Bias 1896; ; ; Burgau Cabeço Cabo de Stª Maria ; ; ; Farol ; 1905; 6 Forte Novo ; Medo branco ; ; Medo das Cascas Olhos de Água ; 24 Pedra da Galé Penedo do Sono Ramalhete ; Srª da Rocha Srª do Livramento Sul da Ponta Baleeira Sul da Ponta do Zavial Sul do Cabo Carvoeiro ; Torre Alta Torre Altinha Torre da Barra Vau 1896; Total 699 Table 1. Historical tuna traps in southern Portugal and years for which data on bluefin catches were recovered (catches in number of fish by commercial categories). 4

5 Month Month Year Total Year Total Total Table 2. Number of tuna traps with monthly catch data recovered (catch in number of BFT, by commercial category) 5

6 TRAP Abobora Barril Cabo Stª Maria Medo das Cascas Srª do Livramento YEAR N W (kg) N W (kg) N W (kg) N W (kg) N W (kg) Total Table 3. Tuna traps and years for which daily catches in number of BFT, by commercial category, and respective weights, were recovered. 6

7 Season: Direito (incoming) Season: Revés (return) Year Nb Traps Atum > 90 kg Atuarro (50-90 kg) Albacora (30-50 kg) Cachorreta (<30kg) Year Nb Traps Atum > 90 kg Atuarro (50-90 kg) Albacora (30-50 kg) Cachorreta (<30kg) Table 4. Recovered information on the number of active traps and catches in number, by commercial category, of bluefin tuna by the Portuguese tuna traps from 1896 to 1972, during the incoming (May- June) and return (July-August) seasons. 7

8 Total Year Nb Traps Atum > 90 kg Atuarro (50-90 kg) Albacora (30-50 kg) Cachorreta (<30kg) Total Table 5. Recovered information on the number of active traps and catches of bluefin tuna in number, by commercial category, by the Portuguese tuna traps from 1896 to

9 BFT Category: CC5 (atum: >= 90 kg) Month Year Total Total BFT Category: CC4 (atuarro: 50>= X < 90 kg) Month Year Total Total BFT Category: CC3 (albacora: 30>= X < 50 kg) Month Year Total Total Table 6. Monthly mean weights for 3 commercial categories of bluefin tuna caught in the traps of southern Portugal 9

10 CC5 CC4 CC3 CC2 Year Atum>90kg Atuarro 50-90kg Albacora 30-49kg Cachorreta <30kg Total ,800, ,930 54, ,491, ,020, , , ,856, ,485, , , ,423, ,792,550 1,007, , ,911, ,454, , , ,544, ,186, , , ,204, ,301,850 54, ,356, ,211,600 1,617, , ,539, ,968,850 1,377,880 60, ,407, ,335, ,990 67, ,575, ,604, ,630 33, ,184, ,770, ,170 31,320 10,380 6,199, ,568, ,860 76,160 31,540 5,242, ,375, , ,600 50,620 4,263, ,510, , ,320 93,600 3,094, ,905, , ,360 13,120 3,367, ,874, , ,520 4,960 3,521, ,207, , , ,780, ,306,150 1,157,520 92, ,555, ,730, ,200 74, ,110, ,627, ,160 21,760 1,820 1,824, ,755, , ,760 2,340 3,160, , ,660 34,440 10,120 1,134, ,601, ,500 54,320 6,540 1,819, ,981, , ,800 22,820 3,385, ,628, ,830 38,160 2,400 1,793, , ,320 75,600 11,860 1,105, ,176,450 82,460 25,600 18,260 1,302, ,231, ,000 15,160 3,160 1,397, ,700 74,130 29,120 9, , ,250 72,170 22,040 61,180 1,039, ,289,750 44, ,334, ,132, ,610 18,040 3,120 3,260, ,320, ,500 22,520 8,040 1,557, ,939, ,680 19,200 1,380 2,087, ,768, ,130 42,720 5,180 2,016, ,095,350 63,350 25,520 2,980 2,187, ,009, ,130 40,560 6,040 2,165, ,002,900 61,180 22,840 4,100 1,091, ,253, ,870 47,840 3,880 1,503, ,454, ,540 98,400 7,900 3,898, ,220, , ,840 6,440 3,600, ,024, , ,640 14,580 1,398, , ,490 62,200 3, , , , ,240 9, , ,090, ,830 73,560 20,520 1,392, ,021, ,130 89,440 11,780 1,308, ,134, , ,320 18,260 3,737, ,802, ,330 99,000 11,840 2,187, ,263, , ,040 17,880 1,761, ,960, ,640 77,200 17,960 3,528, ,610, , ,160 44,360 2,211, ,626, , ,280 45,600 2,148, ,828, , ,520 16,320 2,255, ,159, , ,480 38,420 1,615, ,026, , ,960 20,580 1,434, ,539, , ,200 12,660 2,171, ,305, , ,520 16,740 2,822, , ,770 44,040 21,140 1,259, ,130, ,100 19,600 6,360 1,333, ,075, ,930 39,520 14,760 2,353, , ,360 19,000 7, , , ,460 5,880 3, , ,850 98,700 7, , , ,249,350 35,280 11,440 73,940 1,370, ,393,650 93,940 7,360 77,280 1,572, ,500 31,360 7,440 13, , ,500 35,980 7,360 5, , ,350 14,000 2, , , ,850 20, , ,250 15,890 1,560 40, , ,850 18, , ,600 2, , ,400 4, , , , ,280 31, ,371 11,547 Table 7. Estimated catches, in weight (kg) by commercial categories, of the Bluefin tuna caught by the traps of southern Portugal. 10

11 Figure 1. Bluefin annual mean weight, by fishing season, in the Portuguese traps (D: May June; R: July August) Figure 2. Bluefin annual mean weight, by commercial category, in the Portuguese traps from 1958 to 1972 (CC5: atum > 90 kg; CC4: atuarro: 50>= X < 90 kg; CC3: albacora: 30>= X < 50 kg)) 11

12 Figure 3. Annual bluefin tuna catches in southern Portugal traps (number of fish) 12

13 Figure 4. Size frequencies of Bluefin tuna caught in the Portuguese traps from 1962 to 1970 Figure 5. Bluefin tuna catches by season (in number of fish), in 2 Portuguese tuna traps. 13

14 Figure 6. Daily catches of bluefin tuna (in number of fish), of 2 commercial categories (CC5: atum > 90 kg; CC4: atuarro: >50 < 90 kg), in 5 Portuguese tuna traps, from 1962 to

15 Annex 1: Portuguese imports of Bluefin tuna from Moroccan traps 15

16 Annex: BFT imported from Morocco Bluefin Tuna imported from Marroco (Traps) Year nº weight (t) mean w (kg) Annex 1: Table 1. Portuguese imports of BFT from Moroccan traps Bluefin Tuna imported from Marroco (Traps) Year n w (kg) mean w Annex 1: Table 2. Portuguese imports of BFT from Moroccan traps 16

17 Annex: BFT imported from Morocco Annex 1: Figure 1. Total annual Portuguese imports of BFT from Moroccan traps Annex 1: Figure 2. Annual mean weights of Portuguese imports of BFT from Moroccan traps 17

U.S. Census Bureau News Joint Release U.S. Department of Housing and Urban Development

U.S. Census Bureau News Joint Release U.S. Department of Housing and Urban Development Raemeka Mayo or Stephen Cooper Economic Indicators Division (01) 76-5160 FOR IMMEDIATE RELEASE TUESDAY, MARCH 17, 015 AT 8:0 A.M. EDT NEW RESIDENTIAL CONSTRUCTION IN FEBRUARY 015 The U.S. Census Bureau