Proceedings of the Workshop on the Okhotsk Sea and Adjacent Areas [Vladivostok, June 1995]

I REPORT OF THE PICES WORKSHOP ON THE OKHOTSK SEA AND ADJACENT AREAS (pdf, 0.1 Mb) 1. Outline of the workshop 2. Summary reports from sessions 3. Recommendations of the workshop 4. Acknowledgments II SCIENTIFIC PAPERS SUBMITTED FROM SESSIONS 1. Physical Oceanography Sessions (pdf, 4 Mb) A. Circulation and water mass structure of the Okhotsk Sea and Northwestern Pacific Valentina D. Budaeva & Vyacheslav G. Makarov Seasonal variability of the pycnocline in La Perouse Strait and Aniva Gulf Valentina D. Budaeva & Vyacheslav G. Makarov Modeling of the typical water circulations in the La Perouse Strait and Aniva Gulf region Nina A. Dashko, Sergey M. Varlamov, Young-Ho Han & Young-Seup Kim Anticyclogenesis over the Okhotsk Sea and its influence on weather Boris S. Dyakov, Alexander A. Nikitin & Vadim P. Pavlychev Research of water structure and dynamics in the Okhotsk Sea and adjacent Pacific Howard J. Freeland, Alexander S. Bychkov, C.S. Wong, Frank A. Whitney & Gennady I. Yurasov The Ohkotsk Sea component of Pacific Intermediate Water Emil E. Herbeck, Anatoly I. Alexanin, Igor A. Gontcharenko, Igor I. Gorin, Yury V. Naumkin & Yury G. Proshjants Some experience of the satellite environmental support of marine expeditions at the Far East Seas Alexander A. Karnaukhov The tidal influence on the Sakhalin shelf hydrology Yasuhiro Kawasaki On the formation process of the subsurface mixed water around the Central Kuril Islands Lloyd D. Keigwin Northwest Pacific paleohydrography Talgat R. Kilmatov Physical mechanisms for the North Pacific Intermediate Water formation Vladimir A. Luchin Water masses in the Okhotsk Sea Andrey V. Martynov, Elena N. Golubeva & Victor I. Kuzin Numerical experiments with finite element model of the Okhotsk Sea circulation Nikolay A. Maximenko, Anatoly I. Kharlamov & Raissa I. Gouskina Structure of Intermediate Water layer in the Northwest Pacific Nikolay A. Maximenko & Andrey Yu. Shcherbina Fine-structure of the North Pacific Intermediate Water layer Renat D. Medjitov & Boris I. Reznikov An experimental study of water transport through the Straits of Okhotsk Sea by electromagnetic method Valentina V. Moroz Oceanological zoning of the Kuril Islands area in the spring-summer period Yutaka Nagata Note on the salinity balance in the Okhotsk Sea Alexander D. Nelezin Variability of the Kuroshio Front in 1965-1991 Vladimir I. Ponomarev, Evgeny P. Varlaty & Mikhail Yu. Cheranyev An experimental study of currents in the near-Kuril region of the Pacific Ocean and in the Okhotsk Sea Stephen C. Riser, Gennady I. Yurasov & Mark J. Warner Hydrographic and tracer measurements of the water mass structure and transport in the Okhotsk Sea in early spring Konstantin A. Rogachev & Andrey V. Verkhunov Circulation and water mass structure in the southern Okhotsk Sea, as observed in summer, 1994 Lynne D. Talley North Pacific Intermediate Water formation and the role of the Okhotsk Sea Anatoly S. Vasiliev & Fedor F. Khrapchenkov Seasonal variability of integral water circulation in the Okhotsk Sea B. Sea ice and its relation to circulation and climate V.P. Gavrilo, G.A. Lebedev & A.P. Polyakov Acoustic methods in sea ice dynamics studies Nina M. Pestereva & Larisa A. Starodubtseva The role of the Far-East atmospheric circulation in the formation of the ice cover in the Okhotsk Sea Yoshihiko Sekine Anomalous Oyashio intrusion and its teleconnection with Subarctic North Pacific circulation, sea ice of the Okhotsk Sea and air temperature of the northern Asian continent C. Waves and tides Vladimir A. Luchin Characteristics of the tidal motions in the Kuril Straits George V. Shevtchenko On seasonal variability of tidal constants in the northwestern part of the Okhotsk Sea D. Physical oceanography of the Japan Sea/East Sea Mikhail A. Danchenkov, Kuh Kim, Igor A. Goncharenko & Young-Gyu Kim A “chimney” of cold salt waters near Vladivostok Christopher N.K. Mooers & Hee Sook Kang Preliminary results from a numerical circulation model of the Japan Sea Lev P. Yakunin Influence of ice production on the deep water formation in the Japan Sea 2. Fisheries and Biology Sessions (pdf, 2.8 Mb) A. Communities of the Okhotsk Sea and adjacent waters: composition, structure and dynamics Lubov A. Balkonskaya Exogenous succession of the southwestern Sakhalin algal communities Tatyana A. Belan, Yelena V. Oleynik, Alexander V. Tkalin & Tat’yana S. Lishavskaya Characteristics of pelagic and benthic communities on the North Sakhalin Island shelf Lev N. Bocharov & Vladimir K. Ozyorin Fishery and oceanographic database of Okhotsk Sea Victor V. Lapko Interannual dynamics of the epipelagic ichthyocen structure in the Okhotsk Sea Valentina I. Lapshina Quantitative seasonal and year-to-year changes of phytoplankton in the Okhotsk Sea and off Kuril area of the Pacific Lyudmila N. Luchsheva Biological productivity in anomalous mercury conditions (northern part of Okhotsk Sea) Inna A. Nemirovskaya Origin of hydrocarbons in the ecosystems of coastal region of the Okhotsk Sea Tatyana A. Shatilina Elements of the Pacific South Kuril area ecosystem Vyacheslav P. Shuntov & Yelena P. Dulepova Biota of the Okhotsk Sea: Structure of communities, the interannual dynamics and current status B. Abundance, distribution, dynamics of the common fishes of the Okhotsk Sea Yuri P. Diakov Influence of some abiotic factors on spatial population dynamics of the West Kamchatka flounders (Pleuronectidae) Gordon A. McFarlane, Richard J. Beamish & Larisa M. Zverkova An examination of age estimates of walleye pollock (Theragra chalcogramma) from the Sea of Okhotsk using the burnt otolith method and implications for stock assessment and management Larisa P. Nikolenko Migration of Greenland turbot (Reinhardtius hippoglossoides) in the Okhotsk Sea Galina M. Pushnikova Fisheries impact on the Sakhalin-Hokkaido herring population Vidar G. Wespestad Is pollock overfished? C. Salmon of the Okhotsk Sea: biology, abundance and stock identification Vladimir A. Belyaev, Alexander Yu. Zhigalin Epipelagic Far Eastern sardine of the Okhotsk Sea Yuri E. Bregman, Victor V. Pushnikov, Lyudmila G. Sedova & Vladimir Ph. Ivanov A preliminary report on stock status and productive capacity of horsehair crab Erimacrus isenbeckii (Brandt) in the South Kuril Strait Natalia T. Dolganova Mezoplankton distribution in the West Japan Sea Vladimir V. Efremov, Richard L. Wilmot, Christine M. Kondzela, Natalia V. Varnavskaya, Sharon L. Hawkins & Maria E. Malinina Application of pink and chum salmon genetic baseline to fishery management Vyacheslav N. Ivankov & Valentina V. Andreyeva Strategy for culture, breeding and numerous dynamics of Sakhalin salmon populations Alla M. Kovalevskaya, Natalia I. Savelyeva & Dmitry M. Polyakov Primary production in Sakhalin shelf waters Tatyana N. Krupnova Some reasons for resource reduction of Laminaria japonica (Primorye region) Lyudmila N. Luchsheva & Anatoliy I. Botsul Mercury in bottom sediments of the northeastern Okhotsk Sea Pavel A. Luk’yanov, Natalia I. Belogortseva, Alexander A. Bulgakov, Alexander A. Kurika & Olga D. Novikova Lectins and glycosidases from marine macro and micro-organisms of Japan and Okhotsk Seas Boris A. Malyarchuk, Olga A. Radchenko, Miroslava V. Derenko, Andrey G. Lapinski & Leonid L. Solovenchuk PCR-fingerprinting of mitochondrial genome of chum salmon, Oncorhynchus keta Alexander A. Mikheev Chaos and relaxation in dynamics of the pink salmon (Oncorhynchus gorbuscha) returns for two regions Yuri A. Mitrofanov & Larisa N. Lesnikova Fish-culture of Pacific Salmons increases the number of heredity defects Larisa P. Nikolenko Abundance of young halibut along the West Kamchatka shelf in 1982-1992 Sergey A. Nizyaev Living conditions of golden king crab Lithodes aequispina in the Okhotsk Sea and near the Kuril Islands Ludmila A. Pozdnyakova & Alla V. Silina Settlements of Japanese scallop in Reid Pallada Bay (Sea of Japan) Galina M. Pushnikova Features of the Southwest Okhotsk Sea herring Vladimir I. Radchenko & Igor I. Glebov Present state of the Okhotsk herring stock and fisheries outlook Alla V. Silina & Ida I. Ovsyannikova Distribution of the barnacle Balanus rostratus eurostratus near the coasts of Primorye (Sea of Japan) Galina I. Victorovskaya Dependence of urchin Strongylocentrotus intermedius reproduction on water temperature Anatoly F. Volkov, Alexander Y. Efimkin & Valery I. Chuchukalo Feeding habits of Pacific salmon in the Sea of Okhotsk and in the Pacific waters of Kuril Islands in summer 1993 Larisa M. Zverkova & Georgy A. Oktyabrsky Okhotsk Sea walleye pollock stock status Tatyana N. Zvyagintseva, Elena V. Sundukova, Natalia M. Shevchenko & Ludmila A. Elyakova Water soluble polysaccharides of some Far-Eastern seaweeds 3. Biodiversity Program (pdf, 0.2 Mb) A. Biodiversity of island ecosystems and seasides of the North Pacific Larissa A. Gayko Productivity of Japanese scallop Patinopecten yessoensis (IAY) culture in Posieta Bay (Sea of Japan) III APPENDICES 1. List of acronyms 2. List of participants (Document pdf contains 431 pages)

Recreational anglers' valuation of near-shore marine fisheries in Florida

This report describes and summarizes the results from a state-wide survey of Florida resident saltwater anglers. The survey was designed to provide estimates of the economic value anglers place on marginal changes in management of selected near-shore marine species. The Contingent valuation method was used to elicit angler willingness to pay for changes in management for redfish, seatrout , mullet, sheepshead, pompano. and king mackerel. Contingent valuation is a process in which respondents are presented with a detailed scenario that describes an opportunity to express their willingness to pay for a proposed change in current conditions. The process consists of three parts. First. the change in current conditions, or the "good" to be valued is described. Second, the payment method is described. The payment method is usually closely related to typical methods of buying goods similar to the one to be valued. Finally. the respondent is asked how much they would pay for the good described in the scenario. A special saltwater fishing license stamp that would allow the holder to take advantage of the described management change was used as a payment mechanism. (PDF contains 147 pages.)

Ecologic and hydrographic studies of Elkhorn Slough, Moss Landing Harbor and near coastal waters, July 1974 to June 1976

In July 1974, we began a two-year baseline study of the Moss Landing Elkhorn Slough marine environment for Pacific Gas and Electric Company as mandated by the Coastal Commission. The original proposal included strong recommendations for more complete oceanographic studies and a third year of data collection. These further studies were not funded. This report is divided into three sections: oceanography, benthic invertebrate ecology and fish and zooplankton ecology. (PDF contains 480 pages)

Feeding Ecology of Humpback Whales in Continental Shelf Waters near Cordell Bank, California

Daytime feeding behavior of humpback whales (Megaptera novaeangliae) in Gulf of the Farallones, California, and adjacent waters was observed during autumn of 1988 to 1990. Bodega Canyon, Cordell Bank, and the Farallon Islands were the primary sites of feeding activity. Fecal samples of whales and zooplankton tows contained euphausiids exclusively, dominated by Thysanoessa spinifera (79%), with lesser amounts of Euphausia pacifica (14%), Nyctiphanes simplex (4%), and Nematoscelis difficilis (3%). In 1988 and 1990, whales also were infrequently observed feeding on small schooling fish, presumably Pacific herring (Clupea pallasii), northern anchovy (Engraulis mordax), and juvenile rockfish (Sebastes spp.). Feeding was the most common behavior observed (52%), and less frequently traveling (23%), milling (21 %), and resting (4%). Whales used different methods to consume euphausiid prey at the surface (0-10 m), in shallow water (11-60 m), and deep water (61-140 m). Humpback whales fed at the surface 56% of time in 1988 and 32% of time in 1990, using primarily lateral lunges to capture swarms of euphausiids. In 1989, no surface feeding was observed; however, deep, long-duration dives were followed by extended surface intervals with many respirations. These 1989 observations coincided with increased prey depth as indicated by depth sounder records of diving whales and prey scattering layers. In 1989, increased prey depth and associated feeding behaviors were strongly associated with unusually high surface temperatures, calm seas, and changes in water circulation. Environmental conditions in 1989 triggered the most intense and wide-spread occurrence of red tide in this region since 1980. Red tide samples collected throughout this period contained Alexandrium (=Gonyaulax) catenella and Noctiluca scintillans. Surface feeding was observed only in 1988 and 1990, when surface prey were available and red tides were very limited in extent, duration, and intensity. Annual variations in humpback whale feeding behavior were related to prey availability which is affected by corresponding environmental conditions. (PDF contains 94 pages)

Larvae of Nearshore Fishes in Oceanic Waters near Oahu, Hawaii

Larvae of over 50 families of nearshore fishes were taken in oceanic waters about 13 km offshore of the leeward (southwest) coast of Oahu, Hawaii during 1977-78, The five most frequently taken families (Labridae, Parapercidae, Serranidae, Gobiidae, and Carangidae) made up over 50% of the total nearshore larvae. Most other families were taken very infrequently. Comparison of catch data from three types of nets indicated that 1.25-m diameter bongo nets often sampled larvae as well or better than a 3-m Isaacs-Kidd trawl and that smaller, 70-cm diameter bongo nets were often as effective as the larger nets for certain abundant taxa. Only a few taxa showed evidence of seasonal patterns in abundance. Irregular temporal variability in abundance of some taxa may have been related to occasional recent influxes of surface water from closer to shore. Most larvae taken were late preflexion stage or older. Densities of even the most abundant taxa were rarely greater than 0.001 m-3. The nearshore fish larvae were not dominated by taxa with large larvae or with larvae possessing apparent specializations to pelagic existence, Most taxa taken were pelagic spawners as adults, but larvae of demersal spawners were roughly as well represented as demersal spawners are among the nearshore fish fauna. Previous studies of waters closer to shore probably sampled insufficient volumes for any but a few exceptionally abundant taxa. Sampling with volumes filtered of the order of 104-105 m3 will be necessary to determine if the dominant taxa taken by the present study are ever more abundant closer to shore, (PDF file contains 23 pages.)

History of whaling in and near North Carolina

This study aims to reconstruct the history of shore whaling in the southeastern United States, emphasizing statistics on the catch of right whales, Eubalaena glacialis, the preferred targets. The earliest record of whaling in North Carolina is of a proposed voyage from New York in 1667. Early settlers on the Outer Banks utilized whale strandings by trying out the blubber of carcasses that came ashore, and some whale oil was exported from the 1660s onward. New England whalemen whaled along the North Carolina coast during the 1720s, and possibly earlier. As some of the whalemen from the northern colonies moved to Nortb Carolina, a shore-based whale fishery developed. This activity apparently continued without interruption until the War of Independence in 1776, and continued or was reestablished after the war. The methods and techniques of the North Carolina shore whalers changed slowly: as late as the 1890s they used a drogue at the end of the harpoon line and refrained from staying fast to the harpooned whale, they seldom employed harpoon guns, and then only during the waning years of the fishery. The whaling season extended from late December to May, most successfully between February and May. Whalers believed they were intercepting whales migrating north along the coast. Although some whaling occurred as far north as Cape Hatteras, it centered on the outer coasts of Core, Shackleford, and Bogue banks, particularly near Cape Lookout. The capture of whales other than right whales was a rare event. The number of boat crews probably remained fairly stable during much of the 19th century, with some increase in effort in the late 1870s and early 1880s when numbers of boat crews reached 12 to 18. Then by the late 1880s and 1890s only about 6 crews were active. North Carolina whaling had become desultory by the early 1900s, and ended completely in 1917. Judging by export and tax records, some ocean-going vessels made good catches off this coast in about 1715-30, including an estimated 13 whales in 1719, 15 in one year during the early 1720s, 5-6 in a three-year period of the mid to late 1720s, 8 by one ship's crew in 1727, 17 by one group of whalers in 1728-29, and 8-9 by two boats working from Ocracoke prior to 1730. It is impossible to know how representative these fragmentary records are for the period as a whole. The Carolina coast declined in importance as a cruising ground for pelagic whalers by the 1740s or 1750s. Thereafter, shore whaling probably accounted for most of the (poorly documented) catch. Lifetime catches by individual whalemen on Shackleford Banks suggest that the average annual catch was at least one to two whales during 1830·80, perhaps about four during the late 1870s and early 1880s, and declining to about one by the late 1880s. Data are insufficient to estimate the hunting loss rate in the Outer Banks whale fishery. North Carolina is the only state south of New Jersey known to have had a long and well established shore whaling industry. Some whaling took place in Chesapeake Bay and along the coast of Virginia during the late 17th and early 18th centuries, but it is poorly documented. Most of the rigbt whales taken off South Carolina, Georgia, and northern Florida during the 19th century were killed by pelagic whalers. Florida is the only southeastern state with evidence of an aboriginal (pre-contact) whale fishery. Right whale calves may have been among the aboriginal whalers' principal targets. (PDF file contains 34 pages.)

Ichthyoplankton of the continental shelf near Kodiak Island, Alaska

Eleven ichthyoplankton surveys were conducted (1 in 1972 and 10 between 1977 and 1979) in the northeastern Pacific Ocean over the continental shelf off Kodiak Island, Alaska. In the 677 neuston and 632 bongo tows, eggs or larvae of more than 80 fish taxa were found. They were present in every season and throughout the survey area, although more taxa and more individuals were found in summer than in other seasons. Among the more abundant species were the gadid Theragra chalcogramma and several hexagrammids and pleuronectids. The hexagrammids and several coUids were abundant in the neustonic layer, where they spent close to a year as larvae and prejuvenlles. Although the seasonal and geographic distribution of most taxa was complex, two patterns emerged: Late summer-fall spawners produce demersal eggs and have neustonic larvae that remain pelagic for several months (hexagrammids and some cottlds), and spring-summer spawners have pelagic eggs and larvae that spend several weeks in the plankton but are not closely associated with the surface (Theragra chalcogramma, pleuronectlds). (PDF file contains 95 pages.)

On the physical and biological oceanography near the entrance of the Gulf of California, October 1966-August 1967

ENGLISH: A study of the temporal and spatial distribution of larval tunas and the concomitant oceanic conditions was made in cooperation with the Direccion General de Pesca e Industrias Conexas of Mexico. Field work consisted of eight hydrographic cruises made from October 1966 through August 1967 near the entrance of the Gulf of California. From January through April, surface currents were southerly at velocities up to 20 cm/sec; currents in June were variable in direction and mostly less than 10 cm/sec; by August the surface current was northerly at 10-15 cm/sec. Surface winds were usually secondary to the distribution of mass as an influence on the surface circulation. Currents at 100 m were generally similar in direction to those at the surface, but the water moved more slowly. Between the surface and 100 m, southbound currents crossed the entrance of the Gulf at velocities of 5-10 cm/sec during January and April, forming frontal boundaries with the California Current water, which often occurred south of the entrance. From April to August, the median concentration of surface chlorophyll a increased from 0.65 to 0.97 mg/m3, while the median productivity increased from 5.6 mgC/m3/day in April to 17.8 mgC/m3/day in June before returning to 2.6 mgC/m3/day in August. Primary productivity was closely correlated with the concentration of surface chlorophyll a. Productivity was generally higher in the vicinity of the Gulf than that found for water in the open Pacific. Productivity was highest near Islas Las Tres Marias and second highest near Cabo San Lucas, both locations of local upwelling. The standing crop of phytoplankton was shown to be subjected to progressively heavier grazing pressure in the spring and summer by zooplankton. SPANISH: Un estudio de la distribución temporal y espacial de las larvas de atún y de las condiciones oceánicas concomitantes fue realizado en cooperación con la Dirección General de Pesca e Industrias Conexas de México. El trabajo experimental consistió en ocho cruceros hidrográficos realizados desde octubre 1966 hasta agosto 1967, cerca a la entrada del Golfo de California. De enero a abril, las corrientes superficiales fueron meridionales alcanzando velocidades hasta de 20 cm/seg; las corrientes en junio fueron variables en dirección y la mayoría con una velocidad de menos de 10 cm/seg; en agosto la corriente superficial fue septentrional a 10-15 cm/seg, Los vientos superficiales fueron por lo común secundarios a la dístríbucíón de la masa, como una influencia de la circulación superficial. Las corrientes a 100 m fueron generalmente similares en dirección a las de la superficie, pero el agua se movió más lentamente. Entre la superficie y los 100 m, las corrientes que se dirigen hacia el sur cruzaron la entrada del Golfo a velocidades de 5-10 cm/seg durante enero y abril formando límites frontales con el agua de la Corriente de California, que apareció a menudo al sur de la entrada. De abril a agosto, la concentración media de la clorofila a superficial aumentó de 0.65 a 0.97 mg/m3, mientras que la productividad mediana aumentó de 5.6 mgC/m3/día en abril hasta 17.8 mgC/m3/día en junio antes de regresar a 2.6 mgC/m3/día en agosto. La productividad primaria se correlacionó estrechamente con la concentración de clorofila a superficial. La productividad fue generalmente más alta en la vecindad del Golfo que aquella encontrada en el agua de alta mar del Pacífico. La productividad fue más alta cerca a las Islas Tres Marías, y el segundo máximo fue cerca al Cabo San Lucas, ambas localidades de afloramiento local. Se indicó que la reserva permanente de fitoplancton estaba sujeta por el zooplancton a una fuerta presión progresiva de apacentamiento en la primavera y el verano. (PDF contains 116 pages.)

Some data on landings of pelagic fish by the artisanal fishermen near Freetown during January-December 1978

Pelagic fish (except for tuna) are landed in Sierra Leone mainly by the artisanal fishermen. The two most important species are Sardinella and Ethmalosa.Deep-sea species are normally exploited by purse seiners of foreign countries. The landings of artisanal fishermen largely comprise Sardinella eba.Landing data for Sardinella landed at Tombo and Goderich, and for Ethmalosa at Tombo, are presented in tabular form. Collection methods are described, with a definition of the unit of fishing effort, and a description of the gear used.The landing data are discussed with particular attention to fishing effort, catch per unit effort, and price per ton

The temperature dependence of the development of the embryo in Mesocyclops leuckarti (Claus) and Cyclops scutifer

This work is mainly intended as an addition to the studies of the populations dynamics of Cyclops scutifer, which is part of the ”Latn ja jaure project” (a study of the principles involved in the ecosystem of a small -initially fish free- mountain lake, before and after the introduction of fish). The field work consisted of sampling in Lake Erken in Roslagen in June, July and September, as well as in Latn ja jaure in the Abisko mountains in August and September of 1965. Additional sampling was done in Latn ja jaure for the study of the horizontal, vertical and temporal distribution of Cyclops scutifer, as well as the in situ development of the different stages. These samples have been analysed in such a way as to fit into the frame work of future studies on the population dynamics of Cyclops scutifer, The main aim of the present investigation is the determination of the dependence upon tempera- tare of the development of the embryo in the subarctic Cyclops scutifer as compared with the conditions found in the warm water species Mesocyclops leuckarti.

Mastigophora and Rhizopoda found in saline lakes Weissovo and Repnoie (near Slaviansk). Selected passages describing Ochromonas species and Pedinella. [Translation of: Trudy Obshch.Ispyt.Prir.imp.khar'kov.Univ. 21 119-140, 1888]

This translation includes selected passages of a longer paper on Mastigophora and Rhizopoda found in saline lakes Weissovo and Repnoie. The translation focuses on describing taxonomy and morphology of Ochromonas species and Pedinella. Plates and figures of the original paper are not included in the translation.

A study of flow conditions near the substratum in an experimental channel [Translation from: Verhandlungen der Internationalen Vereinigung fur Theoretische und Angewandte Limnologie 18, 718-725, 1972]

In a slow flow, on a smooth uniform substratum, a limited bed allows the existence of currents slow enough for benthic invertebrates. These conditions rarely occur naturally. The investigations carried out in this work aimed, on an intermediary scale, to define the influence of irregularities in the substratum on flow near the bottom. The substrata used were made of glass marbles. The investigations were carried out in a transparent channel of 70 cm in length and a rectangular section 10 x 5 cm. The data was analysed to study the general evolution of flow in terms of average speeds and the appearance of the turbulence near the bottom.

Langcliffe hatchery investigations 1982 [on River Ribble near Settle]

Langcliffe hatchery investigations looks at fish mortalities for salmon (fry), sea trout, brown trout and rainbow trout, and explores the River Ribble's water supply.

An assessment of the efficiency of three active fish capture methods and a study of roach / bream hybrids on the Crossens drainage system near Southport.

An assessment of three methods of fish capture, to establish the best fishing method which reflects the best range of sizes and species of fish in a given area. The methods used were trawl netting, electrofishing, and seine netting which were assessed on the Crossens drainage system near Southport. The report also includes a study of roach / bream hybrids that were found at the site, which focuses on their distinguishing features and compared with the features of roach and bream.