The Okhotsk Sea and Oyashio Region

This is a final report(1993)of PICES Working Group 1. The objective of the report was to present a review of the importance of the Okhotsk Sea and Oyashio Region on the Ventilation of the North Pacific Ocean, such as the formation of the North Pacific intermediate water. (PDF contains 235 pages)

The relationships between length and weight of yellowfin tuna (Neothunnus macropterus) and skipjack tuna (Katsuwonus pelamis) from the Eastern Tropical Pacific Ocean

ENGLISH: The purposes of the Convention which established the Inter-American Tropical Tuna Commission have been discussed in the Commission's Annual Report for 1950-51 (Schaefer, 1952) and in subsequent Annual Reports. One of its functions is to gather and report on biological information for the tunas of the Eastern Tropical Pacific, the yellowfin tuna (Neothunnus macropterus) and skipjack tuna (Katsuwonus pelamis). This report gives the results of a study of the relationships between the length and the weight of individuals of each of these species, derived from samples of fish of commercial sizes captured during the course of regular fishing operations in several areas of the Eastern Tropical Pacific Ocean SPANISH: Los propósitos de la Convención que estableció la Comisión Interamericana del Atún Tropical han sido expuestos en el Informe Anual de dicho organismo correspondiente a 1950-51 (Schaefer, 1952), y en los siguientes informes anuales. Una de sus funciones es la de recoger información biológica sobre los atunes del Pacífico Oriental Tropical, es decir, el aleta amarilla (Neothunnus macropterus) y el barrilete (Katsuwonus pelamis) y darla a conocer a las partes interesadas. El presente trabajo informativo proporciona los resultados de un estudio de las relaciones entre la longitud y el peso tomados en individuos de cada una de estas especies, mediante muestreo en pescados de tamaños comerciales capturados en el curso de operaciones regulares de pesca, en diversas área del Océano Pacífico Oriental Tropical.

Some features of the autecology and distribution of chaetognatha in the Eastern Tropical Pacific

ENGLISH: The Inter-American Tropical Tuna Commission, in cooperation with the Tuna Oceanography Research program of the Scripps Institution of Oceanography, is studying in the Eastern Tropical Pacific Ocean methods of identifying waters of different characteristics that may influence the distribution and behavior of the tropical tunas. One method of attacking the problem has been to attempt to use zooplankton species as biological indicators of water masses. It has been demonstrated that certain zooplankters have ecological affinities that make them useful for identifying and tracing the movements of water masses. In the Eastern Pacific Ocean, Bieri (1957), Lea (1955), Le Brasseur (1959), Sund (1959), and Sund and Renner (1959) have presented evidence that certain species of Chaetognatha possibly can serve as indicators. The present work reports on a study of the distributions of species of Chaetognatha, obtained from various depths by means of horizontal closing-net hauls, in relation to concurrent measurements of temperature, salinity, and dissolved oxygen. Analyses of these data have provided a basis for determining which species are of potential use as biological indicators within the area of the Eastern Pacific considered in this study. SPANISH: La Comisión Interamericana del Atún Tropical, en cooperación con el programa de la "Tuna Oceanography Research" de la Institución Scripps de Oceanografía, viene estudiando en el Océano Pacífico Oriental Tropical métodos para identificar aguas de características diferentes que podrían influir en la distribución y en el comportamiento de los atunes tropicales. Uno de los métodos para abordar el problema ha sido el de intentar la utilización de especies zooplanctónicas como índices biológicos de masas de agua. Se ha demostrado que ciertos organismos del zooplancton tienen afinidades ecológicas, merced a las cuales son útiles para identificar y trazar los movimientos de las masas de agua. Bieri (1957), Lea (1955), Le Brasseur (1959), Sund (1959) y Sund y Renner (1959) presentaron evidencia de que ciertas especies de quetognatos pueden servir, posiblemente, como tales índices en el Océano Pacífico Oriental. El presente trabajo informa sobre un estudio de la distribución de las especies de quetognatos obtenidos de distintas profundidades por medio de la red de plancton que se cierra en lanzamientos horizontales y en relación con mediciones concomitantes de la temperatura, la salinidad y el oxígeno disuelto. El análisis de estos datos ofreció una base para la determinación de las especies que son potencialmente aptas para ser usadas como índices biológicos dentro del área del Pacífico Oriental a la cual se refiere este estudio.

General review of the Japanese tuna long-line fishery in the Eastern Tropical Pacific Ocean 1956-1962

ENGLISH: This paper constitutes a study of the fishery by Japanese long-line vessels in the area to the eastward of longitude 130°W, which was initiated at the western margin of this region in late 1956 and early 1957, and which has expanded fairly quickly eastward through 1962. The major part of the data was collected by the Nankai Regional Fisheries Research Laboratory (NRFRL) from fishing vessels landing at Tokyo and Yaizu and by the Kanagawa Perfectural Fisheries Experimental Station from fishing vessels landing at Misaki. SPANISH: Este trabajo constituye un estudio de la pesquería efectuada por los barcos Japoneses de palangre en el área hacia el este de los 130°W de longitud, que fue iniciada en el margen occidental de esta región a fines de 1956 y principios de 1957, y que se ha expandido bastante rápidamente hacia el este a través de 1962. (PDF contains 158 pages.)

The age and growth of the tongue sole Cynoglossus canariensis (Steind 1882)

The geometric mean regression equation for the weight; length relationship of Cynoglossus canariensis was W = 0.0025 L super(3.1770). The Von Bertalanffy constants Woo, Loo, K, and to were 507.5852 g, 47.3683 cm, 0.3333 and 0.1397 for males and 839.0753 g, 54.4720 cm, 0.3062 and 0.1737 for females. Total mortality coefficient Z ranged from 0.6482 and 0.8021

Conservation needs of fisheries resources and reorientation for sustainable captive and culture practices

A discussion is presented on the importance of conservation of fishery resources, considering in particular the situation in Nigeria and providing also an outline of various legislations made by government. Suggestions are given regarding the following: education on the importance of conservation; fish farming or aquaculture; restocking or rejuvenation of depleted water bodies; stock assessment; monitoring and surveillance; provision of fishing inputs; and, extension research linkage

Surface currents of the Eastern Tropical Pacific Ocean

(PDF contains 39 pages.)

Icthyofauna of Oramiriukwa River in Imo State, Nigeria

Oramiriukwa one of the rivers in the Imo River drainage basin runs approximately a 14.0km course from its headwaters in Abba Isu (Nwangele LGA) and discharge into Otamiri River. Based on the fish catches of local fishermen using a variety of fishing gear in a sampling station in Emekuku (Owerri LGA), a total of 17 families of fish consisting of 27 species were identified in the river. In the January sample the most numerically abundant species were Tilapia zilli (12.5%). Calamoichthys calabaricus (8.7%) and T. guineensis (8.6%). In the July samples the most numerically abundant species were Mastacemblus loenbergii (9.2%). T. zilli (7.2%) and Hemichromis fasciatus (6.6%). The Shannon Weiner Diversity index for Oranmiriukwa River was high (1.305) implying a relatively diversified and equilibrated fish community

Some freshwater ostracods (Crustacea: Ostracoda) from South Wales

As background to a study of the application of astracods in environmental archaeology, a number of sites in South Wales were visited and sampled. Sites included seven broad environmental categories consisting of lakes, permanent ponds, non-permanent ponds, semi-static canals and reens (drainage ditches), non-permanent small lotic water-bodies, permanent fast-flowing waters and wells. In all, twenty-three species were recorded, and with one exception all belonged to the predominately freshwater Cypridoidea. Overall the most commonly encountered species in South Wales was Cypria ophthalmica. Comparing finds with earlier records, it would appear that Ilyocypris bradyi, Candona pratensis, Eucypris lilljeborgi, Herpetocypris chevreuxi, Potamocypris variegata, P. similis and P. pallida are new additions to the Welsh fauna.

Habitat use by 0+ cyprinid fish in the River Great Ouse, East Anglia

This study was designed to examine the habitat use of several species of 0+ cyprinid in the regulated River Great Ouse and to determine the reasons for specific habitat use. In general, all fish species were found associated with the marginal zone, with little diel variation. Use of shallow habitats in the presence of macrophytes correlated well with the distribution of zooplankton in the river channel, the preferred food source of 0+ cyprinids. During the early to late larval phase, all species fed upon rotifers and diatoms. Cladocera, particularly Alona spp. and Chydorus spp., and early instar larvae of Chironomidae, then became prevalent in the diet along with small numbers of Copepoda. Models were developed to determine habitat availability over a range of discharges, using the physical habitat simulation (PHABSIM) component of the Instream Flow Incremental Methodology (IFIM). The results of this analysis revealed that habitat suitable for 0+ fishes comprised a relatively small percentage of the main channel and generally decreased with discharge.

Observations hydrologique et dynamique le long de deux radiales du plateau continental ivoirien durant l'année focale 1983

In this report, vertical distributions of the temperature and horizontal velocity components of the currents, got from the two sections BELIER (305 1'W) and VRIDI (4°O 5'W), carried out once a week during the 1983 year, on the Continental shelf of Ivory Coast, are shown.

Distribution patterns of tidepool fishes on a tropical flat reef

Rockpools on a tropical f lat reef off the southeastern coast of Brazil were sampled to determine the influence of pool morphometry and water characteristics on fish community structure. The pool closest to the inner fringe of the reef had lower salinity and higher temperature due to inflow of groundwater. The other pools varied only with respect to their morphometric characteristics, algal cover, and bottom composition. Species with a strong affinity for estuarine- like waters characterized the pool closest to the beach and distinguished its fish community from that of the other pools. Instead of being strongly structured by the physicochemical setting and position in the reef, fish communities of the other pools were determined by behavioral preferences and intra- and interspecific interactions. Differences in community structure were related to pool size (the larger sizes permitting the permanency of schooling species), to algal cover (which allowed camouflage for large predatory species), to bottom composition (which provided substrate for turf flora available to territorial herbivores), and to ecological effects (e.g., competition, territoriality, and predation). Although distribution patterns of tidepool fishes have previously been related to the availability of niches, independent of pool position in the reef, our results show synergistic interactions between water properties, presence or absence of niches, and ecological relationships in structuring tidepool fish communities.