摘要:

ABSTRACTFreeze‐branding and tattooing by Panjet were used as techniques for rapid application of batch marks to rainbow trout of stockable size. The subsequent performances of the marks produced were compared. Freeze brands took 2 weeks to become clear and thereafter remained wholly satisfactory for only 1 month. Pigments injected by Panjet were immediately visible but of the dyes tested only Alcian blue remained completely clear after a 3‐month trial. These results are contrasted with those of other workers in trials with various species of freshwater f

ISSN:1355-557X    

DOI:10.1111/j.1365-2109.1981.tb00001.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

ABSTRACTA stomach flushing technique is described which has been used for over a year, both in the laboratory and in the field. It is reliable, quick and relatively easy to perform and has been applied to juvenile Atlantic salmon (Salmo salarL.) and brown trout (S. truttaL.). The only limitation on its use was that fish<4 cm in length were considered too small to flush. Experiments carried out show that the technique removes 98.9% of the stomach contents from the fish and has very little effect on subsequent survival (99.3%) and condition. It is suggested that this technique is an improvement on previous designs.

ISSN:1355-557X    

DOI:10.1111/j.1365-2109.1981.tb00002.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

ABSTRACTInvestigations on the reproductive biology ofPuntius saranaan indigenous species andTiiapia remialli (melanopleura)an exotic, in an ancient man‐made lake, Parakrama Sarnudra (Sea of Parakrama), in Sri Lanka, carried out from February 1978 to May 1979 are presented. The overall female to male ratio inT. rendalliandP. saranawere 1.1:1.0 and 1.5:1.0, respectively. Considerable deviation from the mean ratio was observed and are attributed to their spawning behaviour and migrations. In the larger size groups inT. rendaltimales were dominant while the reverse was observed inP. sarana. Both species were found to breed through out the year, with well defined peaks in the caseof P. saranawhich were coincidental with the main rainy seasons. Both species are multiple spawners, fecundity ranging from 760 to 6160 inT. rendalliwith length and weight varying from 18.8 to 25.8 cm and 126 to 380 g, respectively. InP. sarana. with a length of 23.8–38.0cm and a weight of 180–792 g, fecundity ranged between 16,000 and 29

ISSN:1355-557X    

DOI:10.1111/j.1365-2109.1981.tb00003.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

ABSTRACTThis paper describes the design and construction of a floating fish transporter used in conjunction with a reservoir floating cage rearing unit.

ISSN:1355-557X    

DOI:10.1111/j.1365-2109.1981.tb00004.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

ABSTRACTPOPULATION ESTIMATES, a computer program designed to analyse fish populations in fluctuating streams, is described. Its special feature is to calculate population density (number and g m−2) as a dynamic function of variable stream area. Other output includes estimated population size, mean length, mean weight and mean condition factor. Simulated flow changes of 12.5–400% changed stream surface area 6–37% for straight channels, 11–80% for meandering channels and 18–182% for braided channels. Fish population density, however, may not change inversely proportional to stream size. The main use of POPULATION ESTIMATES is to evaluate the effects of fluctuating flows on fish po

ISSN:1355-557X    

DOI:10.1111/j.1365-2109.1981.tb00005.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

ISSN:1355-557X    

DOI:10.1111/j.1365-2109.1981.tb00006.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Book reviewed in this articleTrout Farming Manual By J. P. STEVENSON.Fish of Rare Breeding: Salmon and Trout of the Donaldson Strains By NEAL O. HINES.Salmon and Sea‐trout Fishing Ed. by ALAN WRANGLESThe Great Salmon Riveis of Scotland — An Angleis' Guide to the Rivers Dee, Spey, Tay and Tweed By JOHN ASHLEY COO

ISSN:1355-557X    

DOI:10.1111/j.1365-2109.1981.tb00007.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY