Early-life-history profiles, seasonal abundance, and distribution of four species of Clupeid larvae from the northern Gulf of Mexico, 1982 and 1983

We present data on ichthyoplankton distribution, abundance, and seasonality and supporting environmental information for four species of coastal pelagics from the family Clupeidae: round herring Etrumeus teres, scaled sardine Harengula jaguana, Atlantic thread herring Opisthonema oglinum, and Spanish sardine Sardinella aurita. Data are from 1982 and 1983 cruises across the northern Gulf of Mexico sponsored by the Southeastern Area Monitoring and Assessment Program (SEAMAP). This is the first such examination for these species on a multiyear and gulfwide scale. Bioproflles on reproductive biology, early life history, meristics, adult distribution, and fisheries characteristics are also presented for these species. During the summer, larval Atlantic thread herring and scaled and Spanish sardines were abundant on the inner shelf <40 m depth), but were rare or absent in deeper waters. Scaled sardine and thread herring were found virtually everywhere inner-shelf waters were sampled, but Spanish sardines were rare in the north-central Gulf. During 1982, larval Atlantic thread herring were the most abundant of the four target c1upeid species, whereas Spanish sardine were the most abundant during 1983. On the west Florida shelf, Spanish sardine dominated larval c1upeid populations both years. Scaled sardine larvae were the least abundant of the four species both years, but were still captured in 25% of inner-shelf bongo net collections. Round herring larvae, collected February-early June (primarily March-April), were abundant on the outer shelf (40-182 m depth) and especially off Louisiana. Over the 2-year period, outer-shelf mean abundance for round herring was 40.2 larvae/10 m2; inner-shelf mean abundances for scaled sardine, Atlantic thread herring, and Spanish sardine were 14.9, 39.2, and 41.9 larvae/l0 m2, respectively. (PDF file contains 66 pages.)

Reproduction, maturation, and seed production of cultured species: Proceedings of the Twelfth U.S.-Japan Meeting on Aquaculture, Baton Rouge, Louisiana, October 25-29, 1983

The United States and Japanese counterpart panels on aquaculture were formed in 1969 under the United States-Japan Cooperative Program in Natural Resources (UJNR). The panels currently include specialists drawn from the federal departments most concerned with aquaculture. Charged with exploring and developing bilateral cooperation, the panels have focused their efforts on exchanging information related to aquaculture which could be of benefit to both countries. The UJNR was begun during the Third Cabinet-Level Meeting of the Joint United States-Japan Committee on Trade and Economic Affairs in January 1964. In addition to aquaculture, current subjects in the program include desalination of seawater, toxic microorganisms, air pollution, energy, forage crops, national park management, mycoplasmosis, wind and seismic effects, protein resources, forestry, and several joint panels and committees in marine resources research, development, and utilization. Accomplishments include: Increased communication and cooperation among technical specialists; exchanges of information, data, and research findings; annual meetings of the panels, a policy-coordinative body; administrative staff meetings; exchanges of equipment, materials, and samples; several major technical conferences; and beneficial effects on international relations. (PDF file contains 79 pages.)

Net phytoplankton and zooplankton in the New York Bight, January 1976 to February 1978, with comments on the effects of wind, Gulf Stream eddies, and slope water intrusions

Results are given of monthly net phytoplankton and zooplankton sampling from a 10 m depth in shelf, slope, and Gulf Stream eddy water along a transect running southeastward from Ambrose Light, New York, in 1976, 1977, and early 1978. Plankton abundance and temperature at 10 m and sea surface salinity at each station are listed. The effects of atmospheric forcing and Gulf Stream eddies on plankton distribution and abundance arc discussed. The frequency of Gulf Stream eddy passage through the New York Bight corresponded with the frequency of tropical-subtropical net phytoplankton in the samples. Gulf Stream eddies injected tropical-subtropical zooplankton onto the shelf and removed shelfwater and its entrained zooplankton. Wind-induced offshore Ekman transport corresponded generally with the unusual timing of two net phytoplankton maxima. Midsummer net phytoplankton maxima were recorded following the passage of Hurricane Belle (August 1976) and a cold front (July 1977). Tropical-subtropical zooplankton which had been injected onto the outer shelf by Gulf Stream eddies were moved to the inner shelf by a wind-induced current moving up the Hudson Shelf Valley. (PDF file contains 47 pages.)

The decline in the commercially important species of fish and predominance of Clarias lazera in Lake Chad

About 86 species of fish have been recorded in the Lake Chad. Most of the species occurring in the lake are widespread including most of the commercially important species. Fish distribution in the lake was adversely affected by the 1972/73 and 1983/84 droughts. The commercially important species before the 1972/73 drought were; Lates, Labeo distichodus, Heterotis, Gymnarchus, Hydrocynus, Citharinus and Bagrus. Other species which had less commercial value at that time include, Clarias, Gnathanemus, Polypterus, Protopterus, Tilapia and Synodontis. Lates niloticus was the most predominant species of commercial importance comprising 50-60% of the total catches of fishermen between 1962 and 1973. Before the 1972/73 drought, occurrence of Clarias lazera was negligible and restricted to long line catches and had little commercial value. As a result of the drought of 1972/73 which resulted in near drying up to the northern sector of the lake, fish populations were confined to isolated pools and were completely scooped out. The remaining fish populations retreated to the southern basin where enough water always remained to hold the surviving representatives of the population. The effects of the drought resulted in occurrence of the little known C. lazera along with other hardy species like Tilapia and Protopterus to dominate the existing fish species composition. In 1976, C. lazera dominated the total catches of fishermen with 85.6%. An overview of the fish population in the lake, their relative abundance, changes in species composition, the effects of drought on the fauna of the lake based on the available data are discussed in this paper

1976 step in the Pacific climate: forty environmental changes between 1968-1975 and 1977-1984

Examination of 40 time series of multidisciplinary environmental variables from the Pacific Ocean and the Americas, collected in 1968 to 1984, demonstrated the remarkable consistency of a major climate-related, step-like change in 1976. To combine the 40 variables (e.g., air and water temperatures, Southern Oscillation, chlorophyll, geese, salmon, crabs, glaciers, atmospheric dust, coral, carbon dioxide, winds, ice cover, Bering Strait transport) into a single time series, standard variants of individual annual values (subtracting the mean and dividing by a standard deviation) were averaged. Analysis of the resulting time series showed that the single step in 1976, separating the 1968-1975 period from the 1977-1984 period, accounted for 89% of variance within the composite time series. Apparently, one of the Earth's large ecosystems occasionally undergoes large abrupt shifts.

The vertical distribution of zooplankton in the Goggausee (the influence of algae and Chaoborus flavicans) [Translation from: Carinthia II 166/186 373-385, 1976]

The Goggausee, a small, shallow, meromictic lake(700m long, 150m wide, max. depth=12m, mean depth=6m), was the site of a week long study (19-26 May 1974) of the limnology department of the University of Vienna. The study comprised pollen analysis and palaeolimnological studies on the one hand, as well as a stock- taking of physiochemical factors, primary production, bacteria, zooplankton, zoo benthos and fish on the other. This paper studies the zooplankton of the lake. The Goggausee is a meromictic lake, with its anoxic deep water, that restricts the vertical distribution of most zooplankton. The aim of the study was to pursue the vertical distribution of the rotifers and Crustacea. Density of individuals, biomass, percentages of zooplankton together and crustaceans and rotifers as groups. Special consideration is given to the the Dipteran Chaoborus flavicans.

On the diel rhythm of motor activity in perch [Translation from: Informatsionnyi Byulleten Biologiya Vnutrennikh Vod No.30, 12-14, 1976]

The river perch (Perca fluviatilis L.) is most active in the daytime hours, and displays seasonal changes of diel rhythm with a break of the rhythm in spring and autumn. In the present work data were obtained on the motor activity of 3 perch measuring l8-20 cm, caught by net in the littoral of a reservoir and spawned under laboratory conditions. The degree of intensity of movement of perch was judged by special experiments. The results are summarised in this short paper.

On the occurrence of Pithophora oedogonia (Mont.) Wittr. var. polyspora Rendle et West fil (Cladophoraceae) in the pond of the Wroclaw Botanical Garden [Translation from: Fragmenta Floristica et Geobotanica 22 255-260, 1976]

Species of Pithophora occasionally appear in Europe and are associated mostly with the tropical, higher water plants, cultivated in numerous botanical gardens. In June 1973 pale green, branched threads were discovered in the pond of the Wroclaw Botanical Garden, amongst filaments of Spirogyra crassa (Kutz.) Czurda emend. and Cladophora glomerata (L.) Kutz. floating on the water surface. They were maintained for several weeks in crude cultures and produced numerous, dark akinetes tightly packed with reserve material. This collected material was found to be a member of the family Pithophora, Wittr. Further examinations identified the material as Pithophora oedogonia. The findings point out that it is probable, that species of Pithophora Wittr. can become acclimatized in Europe, primarily in ponds of botanical gardens, where consequently they are able to tangle easily with higher tropical plants.

Recolonisation of temporary streams and evolution of a degree of stability of the zoocenose [Translation from: Ecologia Mediterranea No.1 149-164, 1976]

When flow returns to a temporary stream a certain number of plant and animal species establish themselves more or less rapidly on the stream-bed constituting the initial phase of evolution of the re-population. This phase is essentially characterised by the ”awakening” of animal species that passed the dry season in a dormant state and by the development of the first unicellular algae that constitute the periphyton. Then they are succeeded by more or less stable animal groups and the structural complexity increases. The authors of the present study aim to analyse the dynamics of community succession from the return of water to the biotope until its drying up. It is attempted to determine the influence of the duration of flow on this evolution. This work is based on the analysis of population diversity with reference to its two complementary aspects, species richness and equitability. The River Destel which was studied for this project is situated in the Gorge of Ollioules near the town of Toulon.

Investigations on saprolegniosis. II. Study on the process of penetrations showing evidence of a proteolytic enzyme and histopathological aspects [Translation from: Riv.ital.Piscicolt.Ittiopatol. 11(4), 109-117, 1976]

The study of enzymatic activity is of great importance in the immunology of fungi. Indeed, knowledge of biological activity of antigenic structures is important for the elucidation of host-parasite relations as well as in the search for a taxonomic factor permitting differential diagnoses. The authors used Saprolegnia cultures to analyse soluble antigenic fractions arising from the mycelium of cultures of 4 species of Saprolegnia, which are found most frequently in the parasitic state on fish: S. parasitica, S. ferax, S. delica, S. diclina. The authors conclude that in the study of saprolegniasis, the enzymatic approach affords new elements for the examination of the etiology of fungi as well as an element of gravity concerning the biochemical modifications necessary to the change of saprophytism to parasitism.

Saprolegnia on roach (Leuciscus rutilus) and carp (Cyprinus carpio) [Translation from: Acta zool.pathol.Antverpiensia 43 107-123, 1976]

There is, in nature, as well as in the aquarium, a parasitic disease known as 'mousse' and which attacks predominantly fish. It is caused by Phycomycete fungi, genus Saprolegnia. The fungus causes external lesions and covers the fish with a thick white layer from whence comes the name 'mousse', commonly attributed to the disease, for which the scientific name is Saprolegnia. This article provides an overview of Saprolegnia infections on fish in nature and aquaria and then discusses symptomology of Saprolegnia in the mirror caro and t roach in more detail.

On the classification of lakes and lake-like bodies of the Ukraine [Translation from: Gidrobiologicheskie Zhurnal, Kiev 19(2) 100-101, 1983]

In the Ukraine there are several thousand large, medium and small lakes and lake-like reservoirs, distinguished by origin, salinity, regional position, productivity and by construction a significant number of large and small water bodies, ponds and industrial reservoirs of variable designation. The problem of national systems necessitates the creation of specific schemes and classifications. Classifying into specific types of reservoir by means of suitable specifications is required for planning national measures with the objective of the rational utilisation of natural resources. It is now necessary to consider the present-day characteristics of Ukranian lakes. In the case of the Ukraine it is possible to use two approaches - genetical and ecological. This paper uses the genetical system to classify the lake-like water bodies of the Ukraine.

Influence of starvation on selected temperatures in the young of bream, roach and perch [Translation from: Informatsionnyi Byulleten Biologiya Vnutrennikh Vod No.50, 45-47, 1981]

Works devoted to the influence of starvation on temperature selection by fishes are few and their conclusions are contradictory. This study determined the influence of brief, up to 14 days, starvation on temperature selection by young fishes. The experiments were carried out in August-September 1976 on fingerling bream (Abramis brama L.), roach (Rutilus rutilus L.) and perch (Perca fluviatilis L.) with body lengths of 3-5 cm and weight 0.5-1.2 g. The young fish were caught in the littoral by seine-nets or small drag-nets. Immediately after catching the fish they were put in acclimatization boxes. The period of acclimatization did not exceed 2 days for bream and roach at a temperature of 20 °C and 6 days for perch at 17 °C. Before the start of the experiment and for the first 10 days of the experiment the fish were fed with oligochaetes, earthworms and daphnia, after that feeding discontinued. At the end of a 10-14 day period the giving of food was resumed. The study concludes that the experiments have shown that in the summer season the factor of starvation significantly changes the reaction to the gradient of temperature in young cyprihids - roach and bream.

Report of the Inter-American Tropical Tuna Commission for the year 1976

ENGLISH: The Inter-American Tropical Tuna Commission operates under the authority and direction of a convention originally entered into by the Republic of Costa Rica and the United States of America. The convention, which came into force in 1950, is open to adherence by other governments whose nationals fish for tropical tunas in the eastern Pacific Ocean. Under this provision the Republic of Panama adhered in 1953, the Republic of Ecuador in 1961, the United Mexican States in 1964, Canada in 1968 and Japan in 1970. In 1967, Ecuador gave notice of her intent to withdraw from the Commission, and her withdrawal became effective on August 21,1968The Commission held its 33rd meeting in Managua, Nicaragua, during October 11-14. SPANISH: La Comisión Interamericana del Atún Tropical está bajo la autoridad y dirección de una convención la cual fue originalmente formada por la República de Costa Rica y los Estados Unidos de América. La Convención, vigente desde 1950, está abierta a la afiliación de otros gobiernos cuyos nacionales pesquen atún en el Pacífico oriental tropical. Bajo esta medida la República de Panamá se afilió en 1953, la República del Ecuador en 1961, los Estados Unidos Mexicanos en 1964, Canadá en 1968 y el Japón en 1970. En 1967, el Ecuador anunció su intención de retirarse de la Comisión y la renuncia se hizo efectiva el 21 de agosto de 1968. La Comisión celebró su XXXIII reunión en Managua, Nicaragua del 11 al 14 de octubre. (PDF contains 180 pages.)

Report of the Inter-American Tropical Tuna Commission for the year 1983

ENGLISH: The Inter-American Tropical Tuna Commission operates under the authority and direction of a convention originally entered into by the Republic of Costa Rica and the United States of America. The convention, which came into force in 1950, is open to adherence by other governments whose nationals fish for tropical tunas in the eastern Pacific Ocean. Under this provision Panama adhered in 1953, Ecuador in 1961, the United Mexican States in 1964, Canada in 1968, Japan in 1970 and France and Nicaragua in 1973. Ecuador withdrew from the Commission in 1968, Mexico in 1978, and Costa Rica in 1979. On October 19 and 20, the Commission held its 41st meeting in Ottawa, Canada. SPANISH: La Comisión Interamericana del Atún Tropical funciona bajo la autoridad y dirección de un convenio establecido originalmente por la República de Costa Rica y los Estados Unidos de América. El convenio vigente desde 1950, está abierto a la afiliación de otros gobiernos cuyos ciudadanos pescan atún en el Pacífico oriental tropical. Bajo esta estipulación, Panamá se afilió en 1953, Ecuador en 1961, los Estados Unidos Mexicanos en 1964, Canadá en 1968, Japón en 1970, Francia y Nicaragua en 1973. Ecuador se retiró de la Comisión en 1968, México en 1978 y Costa Rica en 1979. Como se informó en el informe anual de la Comisión de 1978, la XXXVI reunión de la Comisión, convocada en Tokio (Japón) del 16 al 18 de octubre de 1978, fue suspendida sin haberse adoptado ninguna acción para fijar una cuota de atún aleta amarilla en 1979. La XLI reunión de la Comisión fue convocada en Ottawa (Canadá) del 19 al 20 de octubre de 1983. (PDF contains 272 pages.)