摘要:

Studies were made of the deep water cisco fishery on New York waters of Lake Ontario during the summer and fall of 1942. Experimental gill nets were set to test the 2 3/4 inch mesh, as provided under present New York regulations, against various other mesh sizes to determine if changes in the regulations were advisable in order to increase the production of ciscoes. Conclusions are based on a total catch of 2,393 ciscoes of which 93.23 per cent consisted of a single species, the bloater (Leucichthys hoyi). Characteristics of the different species of ciscoes and fishes associated with them were considered in formulating the recommendations. The catch of bloaters by the nets of each mesh size are analyzed with respect to number of fish taken, average length and weight, sex ratio and condition. Studies on the age and growth of the bloater are presented. A change to 2 1/2 inch mesh was recommended for the deep water ciscoes provided that such nets are not fished in less than 180 feet of water.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1944)74[230:ASOTDC]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1947

数据来源: Taylor

摘要:

The food and feeding habits of the three most important market fish in Hawaiian ponds (Mugil cephalus, Chanos chanos, and Elops machnata) were analyzed to ascertain the position of these fish in the food-chains and the food cycle occurring within the ponds.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1944)74[250:FATFCI]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1947

数据来源: Taylor

摘要:

The food and feeding habits of the influent and subinfluent species (11 fish, 4 shrimps, and 4 crabs) in Hawaiian fish ponds were analyzed to ascertain the biotic interaction. The dominant species were treated in a similar way and reported upon earlier. The ponds are virtually autarchic, and the available food supply is almost totally dependent upon the physical features of the biotope. Microbenthos and detritus were found to support most of the herbivorous species while larger benthos, emergent halophytes, and plankton play minor roles. The animal assemblage within the ponds includes not only herbivores and omnivores but is replete with carnivores, several of which are voracious and reach a large size.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1944)74[262:FATFCI]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1947

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/1548-8659(1944)74[281:RFNSOC]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1947

数据来源: Taylor

摘要:

Feeding sodium chloride in gelatin capsules to brook trout caused a rise in blood salt when amounts of 10, 15, 20, and 25 milligrams were ingested. No effect on the chloride level was found when 5 milligrams were fed. An edema resulted from feeding the two higher levels. This disappeared in the 20 milligram experiment with no loss of fish, but caused a mortality in the 25 milligram level. The absorption curves for salt were similar to those described for carbohydrates. Excretion curves were found to be curvilinear, but showed a break in the two higher levels with the appearance of edema. It was necessary to feed between 0.91 and 1.82 grams of salt per kilogram of body weight to produce a rise in blood salt and between 2.72 and 3.64 grams per kilogram to cause an edema.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1944)74[297:TPEOSC]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1947

数据来源: Taylor

摘要:

The mortality that nearly exterminated the huge stocks of smelt in Lakes Huron and Michigan during the fall and winter of 1942–1943 appears to have originated in central Lake Huron in the Saginaw Bay area in late September or early October 1942. The mortality spread rapidly northward reaching the Drummond Island area about the latter part of October and the St. Ignace region of the Straits of Mackinac near the end of the month. In the latter part of October smelt died also in the Canadian waters of Lake Huron including North Channel and Georgian Bay but exact details as to time and course are lacking. There is some evidence that the epidemic had not reached the Ontario shore of central Lake Huron by late May 1943. Spreading through northern Lake Michigan the mortality had penetrated as far south as Grand Traverse Bay by November 19 and as far west as Point Aux Barques, Michigan, by November 26, 1942. Smelt were reported to be dying in Lake Charlevoix, Michigan, in early February 1943, and in Green Bay toward the middle of that month. The mortality did not reach Crystal Lake where in contrast to Lake Charlevoix a dam barred the passage of fish from Lake Michigan. At the time of the 1943 spring spawning run (April) only a few scattered survivors remained from the vast populations.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1944)74[310:MOSOMM]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1947

数据来源: Taylor

摘要:

Ammonia, nitrite, nitrate, and organic nitrogen were determined at 10-day intervals for 24 ponds at Leetown, West Virginia. These ponds were stocked with 15,000 smallmouth black bass fry per acre and all fish reared in them were counted individually and weighed when the ponds were drained after an average season (during 1943) of 105 days. The purpose of the study was to determine what correlations, if any, existed between fish production and the nitrogen content of the water.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1944)74[338:VINCAF]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1947

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/1548-8659(1944)74[350:ALSOFP]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1947

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/1548-8659(1944)74[360:ATEOTF]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1947

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/00028487.1947.10493248

出版商:Taylor & Francis Group    

年代:1947

数据来源: Taylor