Inter-American Tropical Tuna Commission Comision
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A study of the Eastern Pacific fishery for tuna baitfishes, with particular reference to the anchoveta (Cetengraulis mysticetus) Item Type article Authors Alverson, Franklin G.; Shimada, Bell M. Download date 27/09/2021 21:50:35 Link to Item http://hdl.handle.net/1834/20420 INTER -AMERICAN TROPICAL TUNA COMMISSIONCOMMISSION COMISION INTERAMERICANA DEL ATUN TROPICAL TROPICAL Bulletin - BoletfnBoletín Vol. 11,II, No.2No. 2 A STUDY OF THE EASTERN PACIFIC FISHERY FOR TUNATUNA BAITFISHES, WITH PARTICULAR REFERENCE TO THE THE ANCHOVETA (CETENGRAULlS(CETENGRAULIS MYSTICETUSJ MYSTICETUSJ ESTUDIO DE LA PESQUERIA DE PECES DE CARNADA PARAPARA EL ATUN EN EL PACIFICO ORIENTAL, CON PARTICULARPARTICULAR REFERENCIA A LA ANCHOVETA (CETENGRAULlS (CETENGRAULIS MYSTlCETUSMYST'CETUS J J by - por FRANKLIN G. ALVERSON and - y BELL M. 5HIMADASHIMADA La Jolla,Jollar California 1957 CONTENTS - INDICE ENGLISH VERSION - VERSION EN INGLES Page Introduction _ . 25 Acknowledgements . .... .... ...... .. 25 The fishery for tuna baitfishesbaitfishes....................................... ............... 25 Origin and developmenL . 25 Methods of catching live baiLDan................................... _ . .... 27 Kinds of tuna baitfishes and baiting localities.... 28 Total catch of baitfishes........................................................baitfishes _ _.................. ....... 31 Sources and tabulation of data.....................data _ _ . _...................... 31 Actual and estimated catches by California baitboats keeping logs. 32 Estimated total catch by the entire California tuna fishing fleeLfleet.. _ 33 Comparison of logged bait catches, estimated catches of vessels keeping logs, and estimated total catch _......................._ _ _ 33 Estimated total catches by species and area.....area _ 34 Relationship between total catch of yellowfin and skipjack tuna and the total catch of baitfishesbaitfishes _.. 34 The effects of the tuna-bait fishery upon the populations of the Eastern Pacific baitfishes 35 Consideration of the effects of baiting upon the populations of California sardine, Northern anchovy, Southern anchovy, and GalapagoosGalapago's sardine__ __ 35 Consideration of the effects of baiting upon the populations of anchoveta _ _ 36 Population structure.............................structure.. _. __ . _ __ _ 36 Abundance......Abundance _._ . _ _ _ _ _ _ 36 Total catchca~cIl _ _ _ _ _ 37 Total relative fishing intensity.....................intensity._ _ _ _ 37 Relationship between abundance and fishing intensity............................intensity _ _ 37 Conclusions . ..................................................................., 38 FIGURES - ILUSTRACIONESILUSTRACIONES._ __ . .___ __ _._._.__._ 39 TABLES - TABLAS __ _._ _._._ _ . __ 46 SPANISHSPANISH VERSION - VERSION EN ESPESPAÑOLANOL PaginaPágina Introducci6n._ . .. _ _ __ 62 Reconocimiento _ . _ _ _ _. ._ . _62 La pesqueriapesquería de peces de carnadacarnada.___ __ __ _................._. _.. __ 62 Origen y desarrollodesarrollo._.........__ ._ _. ___ ._ _.........._ _...... 62 MetodosMétodos para la pesca de carnada vivaviva..........................................................._.._........... 64 ClaosesClases de peces de carnada para el atunatún y localidades en que se pescan._ 65 CONTENTS - INDICE (Continued)(Confinued) PáginaPagina Pesca total de peces de carnadacarnada................................................................................ 69 69 Origen y tabulacióntabulacion de los datosdatos.................................................................... 69 69 Pescas reales y pescas estimadas de los barcos de carnada de California que que llevan registros de bitácorabitacora 70 70 EstimaciónEstimacion de la pesca total efectuada por toda la flota atunera de California 71 71 E'studio comparativo de las pescas de carnada anotadas en los registros de de bitácora,bitacora, de las pescas estimadas correspondientes a los barcosbareos que llevan llevan registros y de la pesca total estimada . 71 71 EstimaciónEstimacion de las pescas totales por especies y por áreasareas . 7272 RelaciónRelacion entre la pesca total de atúnatun aleta amarilla y barrilete, y la pescapesca total de peces de carnada . 7373 EfectosEfeetos de la pesqueríapesqueria de carnada para el atúnatun sobre las poblaciones de peces-peces- cebo del PacíficoPacifico OrientaL . 73 73 ConsideraciónConsideracion sobre el efecto de la pesca en las poblaciones de la sardina de de California, anchoa nórdica,nordica, anchoa sureñasurefia y sardina de las Galapagos............Galápagos 73 73 ConsideraciónConsideracion sobre los efectos de la captura de carnada en las poblaciones poblaciones de anchoveta.........anchoveta.......... " '" 74 74 Estructura de la poblaciónpoblacion.................................................................. 75 75 Abundancia.......................... 75 75 Pesca totaL 7676 Intensidad total de la pe-scapooca..................... 7676 RelaciónRelacion entre la abundancia y la intensidad de la pescapesca...... .. 7676 Conclusiones................................................................................................ 78 78 LITERATURE CITED - BIBLIOGRAFIA CITADA 78 78 A STUDY OF THE EASTERN PACIFIC FISHERY FOR TUNA BAITFISHES, WITH PARTICULAR REFERENCE TO THE ANCHOVETA (CETENGRAULlS(CETENGRAULIS MYSTlCETUS)MYSTICETUS) by Franklin G. Alverson and Bell M. Shimada INTRODUCTION Most of the catches of yellowfin and skipjack tuna from the Eastern Pacific Ocean are made by vessels fishing with poIpoleses and lines and live bait. From 1931 to 1954, these baitboats, on the average, accounted for over three-fourths of the total annual California landings of yellowfin and skipjack (Shimada and Schaefer, 1956). With the substantial increase in recent years in the production of the tropical tunas, there have bebeenen greater demands for live bait. This increased need for larger amounts of baitfishes has given rise to important questions relating to the manner in which these populations may be most wisely used. The Inter-American Tropical Tuna Commission has been concerned with various aspects of this problem since its establishment in 1950. This report presents sornesome of the results obtained from the Commis sion's studies of the baitfishes important to the fishery for yellowfin and skipjack tuna. It traces briefly the origin and development of the bait fishery, describes its operations, extent, and yield, and discusses sornesome aspects of the efrectseffects of exploitation upon the Eastern Pacific baitfish populations, particularly of the anchoveta (Cetengmulis mysticetus). ACKNOWLEDGEMENTS Sincere appreciation is expressed to owners and masters of tuna vesvesselsseIs who cooperated by making their fishing records available for study. THE FISHERY FOR TUNA BAITFISHES Origin and development It is difficult to determine exactly how and when the use of live bait carnecame to be an accepted means of catching tunas in the Eastern Pacific region, but is known from recorded accounts (Pacific Fisherman, 1913) that as early as 1910 albacore tuna were being caught off California by fishermen using handlines baited with live sardines. These handlines were replaced in time by bamboo poles and lines, and the technique of scattering live bait on the surface of the water to attract and induce fish to strike at 25 26 ALVERSONALVERSON AND SHIMADA artificial lures was also adopted. These fishing methods were carried overayer to the catching of yellowfin and skipjack tuna about 1918, when the California fishery turned from albacore to the more tropical tuna species (Calif. Bur. Mar. Fish., 1949). The development of the live-bait fishery went hand in hand with the growth and expansion of the yellowfin and skipjack fishery, the general features of which have already been described (Shimada and Schaefer, 1956). The fishery was still of a local nature in the late 1910's and so the first baiting areas were in Southern California, around San Pedro and San Diego. By the early part of the second decade the tropical tuna fishery had moved into Mexican waters as far south as Cape San Lucas (Fig. 1) and by 1925, when the first long-range tuna clipper went into operation, such areas along the Pacific coast of Baja California as Turtle Bay, Abreojos Point, Santa Maria Bay, and Cape San Lucas were established areas of baiting. The importance of Turtle Bay and Magdalena Bay (includ ing adjoining Almejas Bay) increased steadilystcadily as tuna fishing operations centered in these localities, and bait was also taken in limited quantities from numerous intermediate points along the Baja California coast. Baiting in Mexican territorial waters declined in importance, however, in the late 1920's because of large increases by the Mexican government in fees for bait permits. During this period, the Southern California area largely supported the needs of the tuna fishery for live bait. The yellowfin and skipjack tuna fishery expanded rapidly to the south in the 1930's. This expansion was made possible, to a great extent, by the discovery of abundant bait supplies in tropical waters. From information provided by tuna fishermen and by the trade journal Pacific Fisherman (1931, 1932), it is known that the tuna clippers obtained bait during these years from Socorro Island in the Revilla Gigedo group, from Cocos Island, and from the Galapagos Islands. Mention is alsoalso made in these accounts of specific baiting localities along the mainland such as Ceralbo Island, Espiritu Santo Island, Kino Point, and GuaymasGuayrnas