摘要:

Since 1931, the writer has been engaged in making a survey of small lakes and ponds for the New York Conservation Department Biological Survey. During this time, he has observed and studied a large number of new and old artificial lakes. These studies have included, among other important factors in fish production, an analysis of those chemical conditions that directly affect fish life. Studies were made on Minerva Lake over a period of several years after the construction of the lake.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1938)68[303:TCOIWA]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1939

数据来源: Taylor

摘要:

Experiments to determine the relationship between plankton production and fish production were conducted in a series of small, excavated ponds. The ponds were stocked with bluegill bream in May, and received four applications of inorganic fertilizers during the season. Water samples were taken from each pond every two weeks for quantitative and qualitative plankton determinations. The ponds were drained in November and the number and weight of fish from each were recorded. The data indicated that a direct relationship existed between plankton production and fish production.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1938)68[309:TRBPPA]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1939

数据来源: Taylor

摘要:

The changes in the weight of the organs and the body composition (proportions of moisture, proteins, fat, and ash) of four species of trout have been followed during normal growth and after retardation of growth by underfeeding. The eyes tend to continue growth when the fish are underfed. Retarding of growth results in loss of fat and protein accompanied by an increase in the ash content. Underfeeding also results in the loss of fat in trout livers, and in some instances this loss of fat is accompanied by an increase in the iodine number values.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1938)68[316:CPACCO]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1939

数据来源: Taylor

摘要:

Four smallmouth bass streams in the Potomac River watershed are compared. In the largest stream, the Shenandoah River near Berryville, Virginia, the fingerling bass (Micropterus dolomieu) grew to an average length of 4.25 inches during 1936, whereas in the South Branch of the Potomac near Romney, West Virginia, fingerlings attained a length of 2.75 inches by the end of the summer. In the Shenandoah River and probably also in its North Fork, bass grow rapidly and attain the legal size of 10 inches in three years, but in the South Branch of the Potomac and in the Cacapon River from four to six years or more are required for the fish to grow to legal size. The muddy condition of the Shenandoah and North Fork for long periods during the summer affects the success of natural propagation. These streams also have extensive riffle areas over limestone ledges where bass find shelter while feeding. In the South Branch of the Potomac and in the Cacapon River the riffles are short and little shelter is available.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1938)68[322:ACOFES]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1939

数据来源: Taylor

摘要:

The volume and number of organisms per unit area of bottom is now widely used in determining the relative richness of streams. The food grade determined by the volume of organisms in square-foot samples is an important factor in the calculations used to determine the number of fish to plant per mile of stream. In spite of the fact that thousands of dollars may be wasted by making an incorrect estimate no one seems to have investigated some of the fundamental problems involved in the determinations. Some of these problems are: (1) What is an adequate sample; how many square-foot samples are needed to afford a reliable estimate? (2) What is the seasonal fluctuation in food organisms; can samples taken at different seasons be used as reliable estimates? (3) Do all the organisms taken in the samples become available to the same extent to the particular species of fish a stream is to support.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1938)68[336:TDOTFG]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1939

数据来源: Taylor

摘要:

In view of the necessity of securing a method for the most economical transportation of trout, conditions permitting the accommodation of considerable numbers of fingerlings in relatively small volumes of water, have been determined. A uniform distribution of the fish in the tank is obtained through their vertical separation into groups by the use of perforated metallic shelves; this arrangement prevents the huddling of the fish at the bottom of the tank, and their consequent exhaustion through the continuous struggle they exhibit when this crowding occurs. It insures, at the same time, a rapid and constant diffusion of the oxygen which is supplied at the bottom of the tank by highly efficient diffusers.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1938)68[344:OOTROT]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1939

数据来源: Taylor

摘要:

A creel census has been taken on Fife Lake, Michigan, for four successive fishing seasons, 1934 to 1937 inclusive. The data indicate a constant decline in the catch of some species and a corresponding increase in the catch of others. The total take remained relatively constant from year to year; an increase of 92 per cent in fishing effort resulted in an increase in the take of only 16 per cent. Some correlation was found between the percentage of larger piscivorous fish and the size of pan fish in the catch.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1938)68[354:SOAFCC]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1939

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/1548-8659(1938)68[359:PSCP]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1939

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/1548-8659(1938)68[364:POTRAS]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1939

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/00028487.1939.10493067

出版商:Taylor & Francis Group    

年代:1939

数据来源: Taylor