Browsing Flødevigens rapportserie (1982-1992) by Title
Now showing items 27-46 of 67
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Genetic analyses of cod in northern norway. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)Several polymorphic proteins have been used in studies of cod stock structure in northern Norway. Samples of Arctic cod spawning in Lofoten in the spring of 1981 were analysed for enzyme polymorphism by starch gel ... -
Growth of cod in relation to fish size and ration level. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)This study presents the main results of a series of growth experiments on cod with particular reference to ration size, size of the fish and growth and feeding in the spawning season. The experiments were started in ... -
Growth, energy consumption and prey density requirements in first feeding larvae of cod (Gadus morhua L.). In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)Growth, oxygen uptake, swimming activity, feeding ability and energy content were investigated in cod larvae from several groups under different experimental conditions. At yolk absorption the larvae consumed 0.090-0.120 ... -
Growth, mortality and feeding of cod (Gadus morhua L.) larvae in enclosed water columns and in laboratory tanks. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)In April 1982 cod larvae were reared in four 30 l laboratory tanks and in two 300,000 l columnar plastic enclosures for 3-4 weeks from hatching. North Sea oil "production water" was added to one of the enclosures ... -
Gyting hos hyse (Melanogrammus aeglefinus) under experimentelle betingelser
(Flødevigen rapportserie, Research report, 1982)Maturing haddocks were caught in late January 1982 and transferred to a spawning basin at the State Biological Station Flødevigen, Arendal. The spawning took place from February 26th to May 27th, with a maximum in March ... -
Habitat selection and inter year class interactions of young cod (Gadus morhua) in aquaria. In: Flødevigen rapportserie no 1, 1987
(Flødevigen rapportserie, Research report, 1987)Groups of five small (12 - 18 cm) cod were kept in aquaria with two compartments, one with sand and one with stones and algae. When alone, the small fish usually spent most of the time in the compartment with stones and ... -
Habitat selection of juvenile cod (Gadus morhua), whiting (Merlangus merlangius) and some littoral fish in an aquarium. In: Flødevigen rapportserie no 1, 1987
(Flødevigen rapportserie, Research report, 1987)Experiments were conducted to study the habit at selection of juvenile cod Gadus morhua, juvenile whiting merlangus merlangius, black goby Gobius niger, great pipefish Syngnathus acus, sand eel Ammodytes tobianus, ... -
The haemoglobin polymorphism in Atlantic cod (Gadus morhua L.); genotypic differences in somatic growth and in maturing age in natural populations. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)The two common alleles at the polymorphic haemoglobin locus HbI (Sick, 1961) in the Atlantic cod (Gadus morhua L.) code for proteins whose functional properties are differentially influenced by environmental ... -
Hydrografi i Oslofjorden og Langesundsområdet 1974-1978
(Flødevigen rapportserie, Research report, 1982) -
Importance of genetic variation in the propagation of cod. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)During the last decade the existence of genetic diversity within species and populations has been generally accepted. The complex structure of populations as well as the variations within populations is believed to be ... -
Inferences regarding predation on the early life stages of cod and other fishes. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)Little information exists on the predation on the early life stages of marine fish in general and even less on cod. Thus the approach used in this review was to infer the predatory processes that may be significant in ... -
Ingestion of bacteria by cod (Gadus morhua L.) larvae. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)The uptake of Rhodamine-labelled bacteria by cod larvae was demonstrated using a fluorescent microscopy technique, which allowed a quick estimate of bacterial uptake and gut clearance. Live or heat-killed bacteria, ... -
The intensive tearing of juvenile cod, Gadus morhua L. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)Cod were reared in the laboratory from the egg to marketable size using cultured live foods for the early stages and then artificial diets. Survival to metamorphosis was about 10%; subsequent mortalities were negligible. The ... -
Large-scale rearing of cod fry on the natural food production in an enclosed pond. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)For four years (1980-1983) populations of 5 day old cod larvae have been transferred to a dammed seawater pond (60 000 m^3 ). The water volume had been treated with rotenone in advance, and the larvae were released ... -
Large-scale rearing of cod fry on the natural food production in enclosed pond
(Flødevigen rapportserie, Research report, 1983-06) -
Larval fish trophodynamic studies on Georges Bank: sampling strategy and initial results. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)A sampling strategy is outlined to serve as a framework for determining the fine- to micro-scale vertical disribution or fish larvae and their prey on Georges Bank in a single vessel, interdisciplinary mode of operation. ... -
The management of cod stocks with special reference to growth and recruitment overfishing and the question whether artificial propagation can help solve management problems. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)The terms qrowth overfishinq and recruitment overfishinq are defined. The exploitation and management of two of the major cod stocks in the North-East Atlantic, North-East Arctic cod and North Sea cod, are briefly ... -
Mass occurrence of Gyrodinium aureolum Hulburt and fish mortality along the southern coast of Norway in September-October 1981
(Flødevigen rapportserie, Research report, 1982)At the end of September 1981 the sea appeared "coffee brown" along the southern coast of Norway due to mass occurrence of Gyrodinium aureolum Hulburt. The maximum cell concentration observed was 70*10^6 cells*1^-1. When ... -
Morphological, psychological and genetical studies of egg quality in cod (Gadus morhua L.). In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen Rapportserie, Conference object, 1984)The development of cod eggs from various parent fishes was studied. Fertilization success, and proportion of normally developing embryos and larvae varied according to the quality of the eggs. Eggs from poor quality cultures ... -
Neuromasts and cupular growth of cod larvae. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983
(Flødevigen rapportserie, Conference object, 1984)Use of phase contrast microscopy and vital staining showed that newly hatched cod larvae had five free neuromasts on either side of the body and four on the head. About three weeks later, when feeding was established ...