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.

Fischbestände der Ostsee, ihre Entwicklung seit 1970 und Schlussfolgerungen für ihre fischereiliche Nutzung - Teil 2: Hering

The herring of the Baltic Sea shows a complicated population structure. Comparable to herring in other areas it can also be discriminated as spring and autumn spawning herring. Autumn spawning herring has been nearly vanished since the late 1960’s. Baltic Sea spring spawning herring show a broad variety as far as morphometric and other biological characteristics are concerned. It seems not very likely that all those differences are genetically based. The spawning sites of populations are, however, often clearly separated and such groups of herring are in most cases characterized by distinct differences in individual growth. Therefore for assessment purposes it is necessary to distinguish between as small as possible units in order to not endanger smaller populations to become extinct by overexploitation. On the other hand migrations and mixing of herring of different origin especially during the summer feeding period result in extreme difficulties of the discrimination of small units. For this reason only three herring assess ment units have been identified for the central and the northern Baltic Sea: herring in Sub-divisions 25–32+32, herring in Sub-division 30 and herring in Sub-division31. The spring spawning herring of the western Baltic Sea has been combined with spring spawning herring in Division IIIa. Only the herring stock in Sub-division 30 shows a positive development in the past. The largest assessment unit in Sub-divisions 25–29+32 decreased continuously during the whole period 1974–1998. The western Baltic Spring spawning herring stock decreased from 1990 to 1996. There is an ongoing debate on scientific level whether the combination of small populations into large assessment units like the one in S-D’s 25–29&32 might include the danger of the extinction of small compartments of the unit. On the other hand the practice by the International Baltic Sea Fishery Commission of managing the Baltic Sea herring fisheries by dividing a yearly Total Allowable Catch for the whole area among fishery zones without taking care of any biological structure and any individual stock development is totally against the idea of sustainability of fisheries.

Faecal indicator organisms in frozen prawn products. Pt. 2. Survival of the organisms during freezing and frozen storage

The rate of survival of different types of faecal indicator organisms like Escherichia coli, enterococci etc. during freezing and frozen storage has been studied. Peeled and deveined prawns inoculated with a mixed culture of the above organisms were subjected to freezing and storage at -10̊F and examined for over four months.

Distribution and length-weight relationship of tunas and tuna-like fishes around Ceylon

Tunas and tuna-like fishes have contributed considerably towards the increase in fish production from Ceylon's coastal waters, during the last five years and in this blood fish group lies a potential resource for a further increase in production. Consequently considerable attention is being paid to the study of these species. Length frequency sampling of these species are being carried out and quite often it becomes necessary to convert catch in terms of weight to catch in terms of number, when estimating apparent abundance of the stock. The length-weight relationship in addition to its usefulness in converting length frequency data to weight frequency data for such purpose is of general value to biologists and even to fishermen. The six species studied are yellowfin tuna (Thunnus alacares, Bonneterre), skipjack tuna (Katsuwonus pelamis, Linnaeus), mackerel tuna (Buthynnus affinis, Cantor), frigate mackerel (narrow corseleted Auxis thazard, Lacepede and broad corseleted A. rochie, Risso) and bonito (Saida orientalis, T&S).

High temperature processing of fish sausage 2. - Effect of certain preservatives on the shelf life

The effects of preservatives like fat coated sorbic acid (FCSA) and glucono-deltalactone (D-lactone), both separately and in combination, on the shelf life of high temperature (115.6°C for 20 min) processed fish sausage, stored at three different temperatures namely, ambient (28±2° C), cooler storage (2±2°C) and refrigerator (10±2° C) were studied. Whereas the control (without preservative), FCSA, D-lactone and FCSA + D-lactone treated samples could be stored for 9, 11 and 13 days respectively at ambient temperature, those stored at lower temperatures were found to be in acceptable condition for 70 and 80 days respectively. Organoleptic evaluation of taste, flavour the products carried out by panelists revealed that FCSA and FCSA + D-lactone treated samples were unacceptable with regard to the taste, flavour and texture. However, the taste flavour and texture of the control and D-lactone treated samples were in acceptable condition.