摘要:

The use of fish‐parasites as biological tags may become an efficient method of tracing the origin of some migratory fish. The helminth parasites of floundersPlatichthys flesus(L.) from 2 estuaries and from the sea within a 40 mile range were recorded, and an attempt was made to explain the level of infestation of each species of parasite in the 3 localities in relation to their life‐history and the physical nature of the environment. The flounders from the 3 localities were shown to have dissimilar parasite‐faunas, and, therefore, it was possible to characterize the parasite‐fauna for each of the 3 groups of flounders. Individual fish from each locality could be recognized by its parasite‐fauna and especially by the level of certain indicator‐parasites. Similarly, “foreign” flounders moving into a flounder population could be picked out by the markedly different composition of their parasite‐fauna.Podocotylesp. andZoogonoides viviparuswere useful indicator‐parasit

ISSN:0022-1112    

DOI:10.1111/j.1095-8649.1972.tb05645.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

A species of sciaenid fishes is described from Burmese waters and identified withBola chaptisHamilton. On account of the structure of its swim‐bladder and other features it is placed in the same genus,Bahaba, withB. flavolabiataLin, a species of Chinese and Korean water

ISSN:0022-1112    

DOI:10.1111/j.1095-8649.1972.tb05646.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

Confirmatory evidence has been obtained that pre‐spawning losses from ulcerative dermal necrosis (UDN) may have affected recruitment of salmonid stocks in the Lough Erne spawning streams during 1967/6

ISSN:0022-1112    

DOI:10.1111/j.1095-8649.1972.tb05647.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

Six salmonSalmo salar(L.) were vaccinated with an extract of normal salmon skin, to elicit production of anti‐epithelial antibodies. These were produced within 8 weeks and were readily detectable by immunofluorescence, no evidence for the presence of similar antibodies in UDN infected salmon or normal salmon or trout was obtained. Experimental traumatization of the skin of vaccinated salmon with dry ice failed to produce Pemphigus type lesions and it was concluded that UDN was not an auto‐immune disease of the pemphigus t

ISSN:0022-1112    

DOI:10.1111/j.1095-8649.1972.tb05648.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

Diclidophora merlangiis a common parasite of whiting in the Irish Sea. The incidence of infection over an 18‐month period of study varied between 43‐59%. The majority of flukes in single worm infections are found on the 1st gill arch, although in infections of higher intensity increasing numbers of parasites are found on the remaining arches. The factors which may influence the distribution ofDiclidophoraon the host gills are discus

ISSN:0022-1112    

DOI:10.1111/j.1095-8649.1972.tb05649.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

The occurrence of vibrio disease in coalfish, cod, dab, flounders, plaice and salmon from Norwegian waters is described. A description of the pathological findings and of the bacteriological examinations carried out is given. The causative agent was found to beVibrio anguillarum, and the reactions of these Norwegian isolates in relation to previously described biotypes ofV. anguillarumare discussed.

ISSN:0022-1112    

DOI:10.1111/j.1095-8649.1972.tb05650.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

A method of fishing using installations of the fish‐park type, known collectively as acadjas, is common in the coastal lagoons of Dahomey. Acadjas are installed in shallow sheltered waters and are constructed of dense masses of branches planted in the muddy bottom. Two main types exist, small circular acadjavis and large rectangular avas, but these may be combined to give a variety of other forms. After construction the acadjas are left for varying periods before being fished. Many species of fish are found in the installations, but the majority of these are only casual invaders and most of the catch consists of 3 species only. The fish population appears initially to be derived from immigration, but after c. 2 months of implantation, increases exponentially by growth and reproduction. Acadjas that are fished after short periods of installation are therefore regarded as refuge traps, drawing fish from the surrounding environment, where those that are left longer before being fished, develop their own populations. The yield of the acadjas also increases logarithmically with increasing densities of branches planted. Properly managed acadjas may be regarded as a method of fish culture, which, because of the exceptional yields that can be attained, are a potential means of development for shallow mud bottomed waters such as the West African coastal lagoon

ISSN:0022-1112    

DOI:10.1111/j.1095-8649.1972.tb05651.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

A technique for measuring the patterns and levels of swimming activity of unrestrained fish in their natural environment during a period of 24 h is described. The fish were marked with small tags which emitted continuous ultrasonic signals by which they could be located and tracked using submerged, remotely controlled, directional hydrophones. Preliminary results obtained from 2 brown trout (Sahno trutta) showed a pronounced diurnal activity pattern and remarkably low swimming activity levels.

ISSN:0022-1112    

DOI:10.1111/j.1095-8649.1972.tb05652.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

A chromosome study was performed on 2 sympatric species of marine fish,Fundulus heteroclitusL. andF. majalis. A modification of techniques which included the combination of the procedures of McPhail&Jones (1966) with those more recently developed by Ohnuki (1968), for demonstrating the spiral structure of cultured human leukocytes, resulted in clear and distinct chromosome spreads from gill epithelial cells of these 2 species. Optimum chromosome spreading and accumulation of metaphase figures resulted when specimens ofF. heteroclitusreceived either a 0·28 ml or a 0·4 ml injection of a 0·1 % colcemid solution for 45 h and 48 h respectively. Best results inF. majalisoccurred when specimens received a 0·1 ml dose of the 0·1 % colcemid solution for 22 1/2 h. Studies of the karyotypes of 18 specimens ofF. heteroclitusand 9 specimens ofF. majalisindicated that the 2Nchromosome number for each species wa

ISSN:0022-1112    

DOI:10.1111/j.1095-8649.1972.tb05653.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

Sustained swimming abilities of fed and starved larval largemouth bass (Micropterus salmoidesL.) were compared in the first week after swimming initiation. Fed larvae improved to a sustained velocity of 4·0 cm/sec while starved larvae attained a velocity of only 1·5 cm/sec. Swimming behaviour for fed and starved larvae was quantified for number of moves, average distance/move, and total distance for all moves in 1 min intervals. Fed larvae were always more active than starved larvae, although real differences did not appear until the 4th day after swimming initiatio

ISSN:0022-1112    

DOI:10.1111/j.1095-8649.1972.tb05654.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY