Report of the 2004 Workshop on In Situ Iron Enrichment Experiments in the Eastern and Western Subarctic Pacific

Foreword 1. BACKGROUND AND OBJECTIVES (pdf, 0.1 Mb) 2. 2004 WORKSHOP SUMMARY (pdf, < 0.1 Mb) 2.1. What have we learned from the enrichment experiments? 2.2 What are the outstanding questions? 2.3 Recommendations for SEEDS-II 3. EXTENDED ABSTRACTS OF THE 2004 WORKSHOP 3.1 Synthesis of the Iron Enrichment Experiments: SEEDS and SERIES (pdf, 0.5 Mb) Iron fertilization experiment in the western subarctic Pacific (SEEDS) by Atsushi Tsuda The response of N and Si to iron enrichment in the Northeast Pacific Ocean: Results from SERIES by David Timothy, C.S. Wong, Yukihiro Nojiri, Frank A. Whitney, W. Keith Johnson and Janet Barwell-Clarke 3.2 Biological and Physiological Responses (pdf, 0.2 Mb) Zooplankton responses during SEEDS by Hiroaki Saito Phytoplankton community response to iron and temperature gradient in the NW and NE subarctic Pacific Ocean by Isao Kudo, Yoshifumi Noiri, Jun Nishioka, Hiroshi Kiyosawa and Atsushi Tsuda SERIES: Copepod grazing on diatoms by Frank A. Whitney, Moira Galbraith, Janet Barwell-Clarke and Akash Sastri The Southern Ocean Iron Enrichment Experiment: The nitrogen uptake response by William P. Cochlan and Raphael M. Kudela 3.3 Biogeochemical Responses (pdf, 0.5 Mb) What have we learned regarding iron biogeochemistry from iron enrichment experiments? by Jun Nishioka, Shigenobu Takeda and W. Keith Johnson Iron dynamics and temporal changes of iron speciation in SERIES by W. Keith Johnson, C.S. Wong, Nes Sutherland and Jun Nishioka Dissolved organic matter dynamics during SEEDS and SERIES experiments by Takeshi Yoshimura and Hiroshi Ogawa Formation of transparent exopolymer particles during the in-situ iron enrichment experiment in the western subarctic Pacific (SEEDS) by Shigenobu Takeda, Neelam Ramaiah, Ken Furuya and Takeshi Yoshimura Atmospheric measurement by Mitsuo Uematsu 3.4 Prediction from Models (pdf, 0.3 Mb) Modelling iron limitation in the North Pacific by Kenneth L. Denman and M. Angelica Peña A proposed model of the SERIES iron fertilization patch by Debby Ianson, Christoph Voelker and Kenneth L. Denman 4. LIST OF PARTICIPANTS FOR THE 2004 WORKSHOP (pdf, < 0.1 Mb) APPENDIX 1 Report of the 2000 Planning Workshop on Designing the Iron Fertilization Experiment in the Subarctic Pacific (pdf, 1 Mb) APPENDIX 2 Terms of Reference for the Advisory Panel on Iron fertilization experiment in the subarctic Pacific Ocean (pdf, < 0.1 Mb) APPENDIX 3 Historical List of Advisory Panel Members on Iron fertilization experiment in the subarctic Pacific Ocean (pdf, < 0.1 Mb) APPENDIX 4 IFEP-AP Annual Reports (pdf, 0.1 Mb) APPENDIX 5 PICES Press Articles (pdf, 0.6 Mb) (194 page document)

Harmful algal blooms in the PICES region of the North Pacific

Foreword Background and objectives [pdf, 0.84 MB] Country reviews and status reports Section I. Western North Pacific Japan Yasuwo Fukuyo, Ichiro Imai, Masaaki Kodama and Kyoichi Tamai Red tides and harmful algal blooms in Japan [pdf, 0.7 MB] People's Republic of China Tian Yan, Ming-Jiang Zhou and Jing-Zhong Zou A national report of HABs in China [pdf, 0.24 MB] Republic of Korea Sam Geun Lee, Hak Gyoon Kim, Eon Seob Cho and Chang Kyu Lee Harmful algal blooms (red tides): Management and mitigation in Korea [pdf, 0.27 MB] Russia Tatiana Y. Orlova, Galina V. Konovalova, Inna V. Stonik, Tatiana V. Morozova and Olga G. Shevchenko Harmful algal blooms on the eastern coast of Russia [pdf, 1.4 MB] Section II. Eastern North Pacific Canada F.J.R. "Max" Taylor and Paul J. Harrison Harmful marine algal blooms in western Canada [pdf, 0.87 MB] United States of America Vera L. Trainer Harmful algal blooms on the U.S. west coast [pdf, 0.5 MB] Mexico Jose L. Ochoa, S. Lluch-Cota, B.O. Arredondo-Vega, E. Nuñes-Vázquez, A. Heredia-Tapia, J. Pérez-Linares and R. Alonso-Rodriguez Marine Biotoxins and harmful algal blooms in Mexico's Pacific littora [pdf, 0.2 MB] Summary and conclusions [pdf, 0.6 MB] Appendices A. Members of the Working Group [pdf, 0.1 MB] B. Original terms of reference (Vladivostok, 1999) [pdf, 0.08 MB] C. Annual reports of WG 15 [pdf, 0.15 MB] D. Workshop report on taxonomy and identification of HAB species and data management [pdf, 0.15 MB] (Document pdf contains 156 pages)

The valuation of riparian fisheries in Southern and Eastern Africa

This paper reviews the published and gray literature concerning economic valuations of river fisheries in eastern and southern Africa, extracting the best available information on their direct economic values and on the impacts of changes in water management on this value. It then assesses the methods used and makes recommendations regarding approaches to be used in future. The review concentrates on rivers with their associated floodplains and major deltas. The values and issues associated with estuaries and lakes are not considered.

Whales, dolphins, and porpoises of the eastern North Pacific and adjacent Arctic waters: a guide to their identification

This is an identification guide for cetaceans (whales, dolphins, and porpoises), that was designed to assist laymen in identifying cetaceans encountered in eastern North Pacific and Arctic waters. It was intended for use by ongoing cetacean observer programs. This is a revision of an earlier guide with the same title published in 1972 by the Naval Undersa Center and the National Marine Fisheries Service. It includes sections on identifying cetaceans at sea as well as stranded animals on shore. Species accounts are divided by body size and presence or lack of a dorsal fin. Appendices include illustrations of tags on whales, dolphins, and porpoises, by Larry Hobbs; how to record data from observed cetaceans at sea and for stranded cetaceans; and a list of cetacean names in Japanese and Russian. (Document contains 245 pages - file takes considerable time to open)

Ground-water resources of the Oakland Park area of eastern Broward County, Florida

The Oakland Park area obtains its water from the Biscayne aquifer, S composed of very permeable and porous, sandy limestones. The per- 3 meability of the aquifer increases with depth, and wells in the area <\ generally obtain water at depths ranging from 60 to 80 feet, or between S 100 and 200 feet, depending on the quantity of water desired. The data presented in this paper can be used for further development of water and wise management of resources in the area. Large quantities S of ground water are still available at Oakland Park, if salt-water encroachment can be controlled. The data in this study provide the necessary information to begin an effective water management program. (PDF has 49 pages)

Size composition of catches of Yellowfin tuna in the Japanese long-line fishery in the eastern tropical Pacific east of 130°W

ENGLISH (pgs. 267-283): In the spring of 1963, the senior author, who is a member of the staff of the Nankai Regional Fisheries Research. Laboratory, Fisheries Agency, Japanese Government, came to the Institute of Marine Resources of the University of California as a visiting investigator, bringing with him catch statistical data from the fishery in the eastern Pacific, which had been collected at the Nankai Regional Fisheries Research Laboratory (NRFRL) through September 1962, in order to conduct studies of these data in collaboration with the junior author, and with investigators of the InterAmerican Tropical Tuna Commission. A general review of the long-line fishery, based on the catch statistics of the commercial fishing fleet has been published by Suda and Schaefer (1965). In this paper we present an analysis of data respecting the size-composition of yellowfin tuna taken on long-line gear throughout the eastern Pacific between 1958 and 1962, and make some comparisons with data on size-composition of yellowfin tuna taken in the near-surface fishery, by bait boats and purse-seiners, in waters adjacent to the American coast. As has been shown by Suda and Schaefer (1965), the long-line fishery in the eastern Pacific is primarily directed toward the capture of bigeye tuna. However, considerable quantities of yellowfin tuna are also taken on this gear, and, in addition, there are substantial catches of albacore and of several species of spearfishes in some parts of the range of this fishery. Information respecting the catch rates of yellowfin tuna, and information respecting the size-composition of the stock of yellowfin tuna being exploited by the long-line fishery, is of particular interes~" because the yellowfin tuna population of the eastern Pacific is also subject to an intensive fishery by baitboats and purse-seiners which capture this species, together with skipjack, near the surface along the coast of the Americas, and around the outlying islands, in the region of California to northern Chile. SPANISH (pgs. 311-329): En la primavera de 1963, el autor principal, quien es miembro del personal del Nankai Regional Fisheries Research Laboratory, Fisheries Agency del gobierno japonés, vino al Institute of Marine Resources de la Universidad de California en calidad de investigador visitante y trajo consigo datos estadísticos de las capturas de la pesquería en el Pacífico oriental, que habían sido recolectados en el Nankai Regional Fisheries Research Laboratory (NRFRL) hasta septiembre de 1962, con el fin de hacer estudios de esos datos en colaboración con el coautor y con investigadores de la Comisión Interamericana del Atún Tropical. Una revisión general de la pesquería con palangre, basada sobre las estadísticas de captura de la flota pesquera comercial, ha sido publicada por Suda y Schaefer (1965). En este trabajo presentamos un análisis de los datos correspondientes a la composición de tamaños del atún aleta amarilla capturado con equipo palangrero en todo el Pacífico oriental, entre 1958 y 1962, y hacemos algunas comparaciones con los datos sobre la composición de tamaños del atún aleta amarilla cogido en la pesquería superficial cercana, por barcos de carnada y rederos en aguas adyacentes a la costa americana. Como ha sido demostrado por Suda y Schaefer (1965) la pesquería con palangre en el Pacífico oriental tiene como principal objeto la captura del atún ojo grande. Sin embargo, considerables cantidades de atún aleta amarilla son capturadas también por este equipo y, además, hay también considerables capturas de albacora y de diversas especies de peces-espada en algunas partes de la región que abarca esta pesquería. La información respecto a las tasas de captura del atún aleta amarilla, y la relativa a la composición de tamaños del stock de esta especie que explota la pesquería con palangre, es de particular interés, a causa de que la población de atún aleta amarilla del Pacífico oriental es también objeto de una pesca intensiva por barcos de carnada y rederos que capturan esta especie, junto con el barrilete, cerca de la superficie a 10 largo de la costa de las Américas y alrededor de las islas mar afuera, en la región desde California hasta el norte de Chile.

Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest): Black, green, and red abalones

All abalones belong to the genus Haliotis sensu latu, family Haliotidae. The 75 species known worldwide (Booloot ian et, al. 1962) are anatomically similar and all are adapted for attachment to hard substrates. Seven species are widely distributed along the coast of California (Cox 1962; Mottet 19781, of which several are important in the comercial and sport fisheries of the Pacific Southwest. (PDF has 19 pages.)

Assessment of Atlantic Red Drum for 1999: Northern and southern regions

An assessment of the status of the Atlantic stock of red drum is conducted using recreational and commercial data from 1986 through 1998. This assessment updates data and analyses from the 1989, 1991, 1992 and 1995 stock assessments on Atlantic coast red drum (Vaughan and Helser, 1990; Vaughan 1992; 1993; 1996). Since 1981, coastwide recreational catches ranged between 762,300 pounds in 1980 and 2,623,900 pounds in 1984, while commercial landings ranged between 60,900 pounds in 1997 and 422,500 pounds in 1984. In weight of fish caught, Atlantic red drum constitute predominantly a recreational fishery (ranging between 85 and 95% during the 1990s). Commercially, red drum continue to be harvested as part of mixed species fisheries. Using available length-frequency distributions and age-length keys, recreational and commercial catches are converted to catch in numbers at age. Separable and tuned virtual population analyses are conducted on the catch in numbers at age to obtain estimates of fishing mortality rates and population size (including recruitment to age 1). In tum, these estimates of fishing mortality rates combined with estimates of growth (length and weight), sex ratios, sexual maturity and fecundity are used to estimate yield per recruit, escapement to age 4, and static (or equilibrium) spawning potential ratio (static SPR, based on both female biomass and egg production). Three virtual analysis approaches (separable, spreadsheet, and FADAPT) were applied to catch matrices for two time periods (early: 1986-1991, and late: 1992-1998) and two regions (Northern: North Carolina and north, and Southern: South Carolina through east coast of Florida). Additional catch matrices were developed based on different treatments for the catch-and-release recreationally-caught red drum (B2-type). These approaches included assuming 0% mortality (BASEO) versus 10% mortality for B2 fish. For the 10% mortality on B2 fish, sizes were assumed the same as caught fish (BASEl), or positive difference in size distribution between the early period and the later period (DELTA), or intermediate (PROP). Hence, a total of 8 catch matrices were developed (2 regions, and 4 B2 assumptions for 1986-1998) to which the three VPA approaches were applied. The question of when offshore emigration or reduced availability begins (during or after age 3) continues to be a source of bias that tends to result in overestimates of fishing mortality. Additionally, the continued assumption (Vaughan and Helser, 1990; Vaughan 1992; 1993; 1996) of no fishing mortality on adults (ages 6 and older), causes a bias that results in underestimates of fishing mortality for adult ages (0 versus some positive value). Because of emigration and the effect of the slot limit for the later period, a range in relative exploitations of age 3 to age 2 red drum was considered. Tuning indices were developed from the MRFSS, and state indices for use in the spreadsheet and FADAPT VPAs. The SAFMC Red Drum Assessment Group (Appendix A) favored the FADAPT approach with catch matrix based on DELTA and a selectivity for age 3 relative to age 2 of 0.70 for the northern region and 0.87 for the southern region. In the northern region, estimates of static SPR increased from about 1.3% for the period 1987-1991 to approximately 18% (15% and 20%) for the period 1992-1998. For the southern region, estimates of static SPR increased from about 0.5% for the period 1988-1991 to approximately 15% for the period 1992-1998. Population models used in this assessment (specifically yield per recruit and static spawning potential ratio) are based on equilibrium assumptions: because no direct estimates are available as to the current status of the adult stock, model results imply potential longer term, equilibrium effects. Because current status of the adult stock is unknown, a specific rebuilding schedule cannot be determined. However, the duration of a rebuilding schedule should reflect, in part, a measure of the generation time of the fish species under consideration. For a long-lived, but relatively early spawning, species as red drum, mean generation time would be on the order of 15 to 20 years based on age-specific egg production. Maximum age is 50 to 60 years for the northern region, and about 40 years for the southern region. The ASMFC Red Drum Board's first phase recovery goal of increasing %SPR to at least 10% appears to have been met. (PDF contains 79 pages)

Distribution and abundance of ichthyoplankton in Florida Bay

Ichthyoplankton was sampled at 14 stations with 60 cm bongo nets fitted with 0.333 mm mesh in basins throughout Florida Bay in 1994-1995. In addition, I compared collections made using an epibenthic sled to those made with standard ichthyoplankton bongo nets at four stations during July 1997-November,1999 to determine ifthe two types of gear are complementary. In 1994-1995, in descending order of abundance, Clupeiformes, Gobiidae, Callionymidae, Sciaenidae, Labrisomidae, Soleidae and Blenniidae dominated the ichthyoplankton. Densities of clupeiforms were generally very high (> 100 larvae 100 m-3) or high (10.0 - 99.9 larvae 100 m-3). Gobiid larvae were ubiquitous with highest densities occurring in waters in close proximity to the Gulf of Mexico (109.7 larvae 100 m-3), lowest in two ofthree eastern Florida Bay stations (<1.0 larva 100 m-3). Spotted seatrout, Cynoscion nebulosus, dominated larval sciaenid collections and the only other sciaenid identified to species was the sand seatrout, Cynoscion arenarius. Taxa differed markedly between collections taken by epibenthic sled and standard ichthyoplankton bongo nets. Taxa collected with standard ichthyoplankton gear were those that spawn in Florida Bay and have pelagic larvae (i.e., engraulids and gobiids). Taxa collected with the sled were small resident species that have benthic larvae (i.e., syngnathids and cyprinodonts) or taxa that spawn outside the bay, but use the bay as a nursery area (i.e., gerreids and haemulids). Recently-settled red drum, Sciaenops ocellatus, were collected with the epibenthic sled in November 1999, although juveniles of this important gamefish are rare in the bay.

An evaluation of Northern Florida Bay as a nursery area for red drum, Sciaenops ocellatus, and other juvenile and small resident fishes.

Red drum is one ofthe most popular species sought by anglers in Florida Bay, yet juveniles are rarely encountered. We evaluated Florida Bay as a nursery area for red drum by sampling for recently-settled late larvae in basin areas within the bay with an epi-benthic sled at six stations in November 2000, and at seven stations during December 2000 through February 2001. In November 2000 we surveyed potential sampling sites in quiet backwaters adjacent to mangroves for juvenile red drum. A total of 202 sites were sampled mainly in northern Florida Bay and adjacent waters with a cast net. We collected only one recently-settled red drum larvae and no juveniles. Obviously the sites that we sampled in Florida Bay and adjacent waters are not nursery habitat for this valuable species. Sled collections were dominated by bay anchovy, Anchoa mitchilli, but densities were biased by one collection. Five small resident species were among the dominant species: rainwater killifish, Lucania parva; dusky pipefish, Syngnathus floridae; dwarf seahorse, Hippocampus zosterae; and clown goby, Microgobius gulosus. Three species that spawn outside Florida Bay in the GulfofMexico were common: pinfish, Lagodon rhomboides; pigfish, Orthopristis chrysoptera; and silver perch, Bairdiella chrysoura. Twenty-seven species were collected with the cast net. Hardhead silversides (Atherinomorus stipes), bay anchovy, tidewater mojarra (Eucinostomus harengulus), silver jenny (Eucinostomus gula), and goldspotted killifish (Floridichthys carpio) were the most common in cast net collections. Although only one red drum was collected, we were able to: (1) identify mesohaline waters from our cast net sites to test our preliminary assessment that mesohaline habitat might be limited in Florida Bay, (2) document the distribution and abundance of fishes collected by cast net that should enhance our understanding of ichthyofauna in the Northern Subdivision ofFlorida Bay and adjacent waters, and (3) from epibenthic sled collections, describe the habitats, abundance and distribution of recently settled larvae/small juveniles/small resident fishes during late fall and winter. This information should be useful to managers and future research. (PDF contains 34 pages)

Bag and size limit analyses for red drum in Northern and Southern Regions of the U.S. Atlantic

Assessments of the Atlantic red drum for the northern (North Carolina and north) and southern (South Carolina through east coast of Florida) regions along the U. S. Atlantic coast were recently completed. The joint Red Drum Technical Committee (SAFMC/ASMFC) selected the most appropriate catch matrix (incorporating an assumption on size of recreationally-released fish), selectivity of age 3 relative to age 2, and virtual population analysis (FADAPT). Given gear- and age-specific estimates of fishing mortality (F) for the 1992-1998 period, analyses were made of potential gains in escapement through age 4 and static spawning potential ratio (SPR) from further reductions in fishing mortality due to changes in slot and bag limits. Savings from bag limits were calculated given a particular slot size for the recreational fishery, with no savings for the commercial fisheries in the northern region due to their being managed primarily through a quota. Relative changes in catch-at-age estimates were used to adjust age-specific F and hence calculated escapement through age 4 and static SPR. Adjustment was made with the recreational savings to account for release mortality (10%, as in the stock assessment). Alternate runs for the northern region commercial fishery considered 25% release mortality for lengths outside the slot (instead of 0% for the base run), and 0% vs. 10% gain or loss across legal sizes in F. These results are summarized for ranges of bag limits with increasing minimum size limit (for fixed maximum size), and with decreasing maximum size limit (for fixed minimum size limit). For the southern region, a bag limit of one-fish per angler trip would be required to attain the stated target of 40% static SPR if the current slot limit were not changed. However, for the northern region, a bag limit of one-fish per angler trip appears to be insufficient to attain the stated target of 40% static SPR while maintaining the current slot limit. (PDF contains 41 pages)

Additional information on the length-weight relationship of skipjack tuna from the Eastern Tropical Pacific Ocean

ENGLISH: Results of a study of the length-weight relationships of yellowfin (Neothunnus macropterus) and skipjack (Katsuwonus pelamis) tuna from several fishing areas of the Eastern Tropical Pacific Ocean have been published by Chatwin (1959). In that report, a very low exponential value of 2.6261 was obtained for skipjack from Area 14 (off northern Chile, see Chatwin, Figure 1). It was pointed out, however, that this estimate was based on two samples of fish with a very narrow range of total lengths, not representative of the range in the catch, and that it would be desirable to obtain a further estimate based on a larger range of total lengths. In addition, there proved to be significantly large differences among exponents for the areas sampled, precluding use of a single regression equation for all areas. Two important fishing areas remained unsampled (Areas 10 and 13, see Chatwin, Figure 1), and it appeared desirable to collect length-weight measurement data from them, so that estimating equations would be available for all areas. Subsequent to publication of Chatwin's study, samples of skipjack length-weight measurements were obtained from the desired areas. Estimates derived from these data, and their effects on the previous analysis are presented herein. SPANISH:Los resultados de un estudio sobre las relaciones entre la longitud y el peso del atún aleta amarilla (Neothunnus macropterus) y del barrilete (Katsuwonus pelamis) de las diferentes áreas de pesca en el Pacífico Oriental Tropical ya han sido publicados por Chatwin (1959). En ese informe se obtuvo un valor exponencial muy bajo de 2.626 para el barrilete del Area 14 (frente a la costa norte de Chile, ver Chatwin, Figura 1). Se hizo hincapié, sin embargo, en que esta estimación se basaba en dos muestras de peces con una amplitud muy estrecha de longitudes totales, no representativa de la amplitud en la pesca, y que sería deseable obtener una estimación adicional basada en una amplitud mayor de longitudes totales. Además, se comprobó que habian diferencias significativamente grandes entre los exponentes de las áreas muestreadas lo que impedía el usa de una sola ecuación de regresión para todas las áreas. Se quedaron sin muestrear dos importantes áreas de pesca (Areas 10 y 13, ver Chatwin, Figura 1) y pareció deseable recolectar datos de medidas de longitud y peso de estas áreas, de tal manera que hubiesen disponibles ecuaciones estimadoras para todas las áreas. Después de la publicación del estudio de Chatwin, so obtuvieron muestras de medidas de longitud y peso de barriletes de las áreas deseadas. Las estimaciones derivadas de estos datos y sus efectos sabre el análisis previo se dan en el presente informe.

Distribution of fishing effort and resulting tuna catches from the Eastern Tropical Pacific by quarters of the year, 1951-1958

ENGLISH: This is a data report based on information collected from the logbooks of baitboats and purse-seiners engaged in the fishery for yellowfin (Neothunnus macropterus) and skipjack (Katsulvonus pelamis) tuna in the Eastern Tropical Pacific Ocean from 1951 through 1958. The detailed analysis of these data appears in other research bulletins, some already published and others in preparation. SPANISH: Este es un informe basado en los datos contenidos en la información recogida de los registros de bitácora de los barcos de carnada y rederos que se dedicaron a la pesca de atún aleta amarilla (Neothunnus macropterus) y barrilete (Katsuwonus pelamis) en el Océano Pacífico Oriental Tropical de 1951 a 1958. El análisis detallado de estos datos aparece en otros boletines de investigación, algunos de los cuales ya han sido publicados y otros están en preparación.

Species and size relationships within schools of yellowfin and skipjack tuna as indicated by catches in the Eastern Tropical Pacific Ocean

ENGLISH: Yellowfin tuna, Neothunnus macropterus, and skipjack tuna, Katsuwonus pelamis, are fished intensively off the west coast of the Americas in an area from about the California-Mexico border in the north to the Peru-Chile border in the south. The historical development of this fishery, and its expansion by the long-range California fleets of bait and purse-seine vessels, are well documented by Godsil (1938), Scofield (1951) and Shimada and Sehaefer (1956). The quarterly distribution of the tuna catches within this area has been reported for some recent years by Alverson (1959). SPANISH: Los atunes aleta amarilla, Neothunnus macropterus, y barrilete, Katsuwonus pelamis, son pescados con intensidad frente a la costa occidental del continente americano, en un área comprendida más o menos entre la frontera California-México en el norte y el límite Perú-Chile en el sur. El desarrollo histórico de esta pesquería y la expansión que le han dado las flotas californianas de largo radio de acción, formadas por los barcos de carnada y rederos, están bien documentados por Godsil (1938), Scofield (1951) y Shimada y Schaefer (1956). La distribución trimestral de las pescas de atún dentro de esta área ha sido tratada por Alverson (1959) con referencia a años recientes.