ISSN:0002-8487    

DOI:10.1577/00028487.1943.10493108

出版商:Taylor & Francis Group    

年代:1943

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/00028487.1943.10493109

出版商:Taylor & Francis Group    

年代:1943

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/00028487.1943.10493110

出版商:Taylor & Francis Group    

年代:1943

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/00028487.1943.10493111

出版商:Taylor & Francis Group    

年代:1943

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/00028487.1943.10493103

出版商:Taylor & Francis Group    

年代:1943

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/00028487.1943.10493104

出版商:Taylor & Francis Group    

年代:1943

数据来源: Taylor

摘要:

A practical and economical method for anaesthetizing adult salmon and steelhead trout in the fish trucks used in the Grand Coulee fish salvage program is described. The method consists in generating a predetermined carbon-dioxide concentration in the 1000-gallon tanks of the trucks through the successive addition of predissolved sodium bicarbonate and dilute sulphuric acid in proper quantities. Carbon-dioxide anaesthesia effectively solved the acute problem of species segregation in the fish salvage program and, with minor modifications, could be used with equal success in certain hatchery operations necessitating the handling of large fish.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1942)72[25:TAOFBH]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1943

数据来源: Taylor

摘要:

A nutritional disease of trout, caused by a diet deficient in Vitamin B1(thiamin), is described. The symptoms are attributable, either primarily or secondarily, to malfunctioning of the nervous system and are: Loss of equilibrium accompanied by whirling, melanotic appearance, inability to feed in the latter stages of the disease, progressive weakness, and a final paralysis. It was produced in the laboratory by feeding a diet known to be lacking in thiamin. The disease was cured by injections of thiamine hydrochloride.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1942)72[30:VBDIHR]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1943

数据来源: Taylor

摘要:

A population study was conducted on 580.5 feet of Hunt Creek, a tributary of the Thunder Bay River, in Montmorency County, Michigan. Hunt Creek was open to public fishing over its entire length during the 1940 trout season. A combination of stream diversion, blocking and seining, and finally poisoning with rotenone, enabled the investigators to obtain a capture of all fish in 0.131 acres of stream. The total fish population consisted of 605 brook trout weighing 12.36 pounds, and 188 muddlers weighing 1.27 pounds. From these data it was computed that Section C of Hunt Creek was supporting 4,619 brook trout (weight, 94.40 pounds) and 1,435 muddlers (weight, 9.68 pounds) per acre. Of the 605 brook trout captured, 2.3 per cent (14) were legal-sized (7 inches, total length or longer); 22.0 per cent (133) were between 4 and 6.9 inches; and 75.7 per cent (458) were between 2 and 4 inches long. Two and one-half times as many legal-sized brook trout were captured in the deeper portion of the area as in the shallower region. Analysis of the data indicates that seining as a method of capture, even in blocked-off portions of trout streams, has an efficiency of no more than about 80 per cent, as far as number is concerned.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1942)72[35:APSOAL]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1943

数据来源: Taylor

摘要:

Pre-impoundment bottom-fauna data are presented for the Watts Bar Reservoir area (Tennessee). A salting-out technique is described which was used to facilitate the separation of organisms from debris. In deep water four major taxonomic groups made up 98.93 per cent of the total number and practically 100 per cent of the total volume. Nymphs of Hexagenia bilineata (Say) composed 82.43 per cent of the total volume. This species probably has a 1-year life cycle in Tennessee. Production was highest on the muddy bottom and lowest on sand. Data on depth distribution showed the first 10 feet to be most productive. The seasonal peak of production was reached during September and October. This maximum was due almost entirely to mayflies. The rate of growth of Hexagenia nymphs was most rapid during August and September or immediately following hatching. The riffles and flats at the shallow-water station were less productive than the mud-sand bottom of the deep water. The fauna of the riffles and flats will probably not survive impoundment; however, the fauna of the deep-water area will survive.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1942)72[52:APBSOW]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1943

数据来源: Taylor