摘要:

Partial creel censuses were operated on five of the Fish River Lakes in 1957-59 and on one of the lakes in 1954 and 1961 also. The salmon and brook trout fishing in general compared favorably with other large Maine lakes. Fishing success in Square Lake declined by 62 percent between 1954 and 1961. The decline is attributed to a reduced growth rate that delayed attainment of legal length. Salmon caught by anglers from all the lakes were primarily ages III-VI. Estimated yield to the angler ranged from 0.13 to 0.68 pound per acre. Brook trout were generally less abundant than salmon in the sport fishery. Trout were shorter lived than salmon and suffered a higher total mortality. The growth rates of salmon in the lakes are compared, and management possibilities are discussed for the different lakes.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1963)92[193:TSATFO]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1963

数据来源: Taylor

摘要:

A program was initiated in 1956 to evaluate current hatchery practices and to determine ways of improving the rearing and liberation of juvenile steelhead trout. The physiological changes which result in the seaward migration of wild juvenile steelhead appear to occur most frequently when the fish are in the 14- to 18-centimeter length range. These fish may be 1 to 3 years of age, but the majority are 2 years old. Hatchery-reared steelhead exhibited the highest survival as returning adults when liberated at a length of 16 centimeters or longer. Results indicate that the optimum release date for hatchery-reared steelhead coincides with the peak movement downstream of wild Steelhead smolts.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1963)92[202:TSMARO]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1963

数据来源: Taylor

摘要:

Short-term effects of DDT upon summer populations of plankton animals in some Minnesota ponds are reported. DDT in bentonite and vermiculite granules was applied to three ponds in amounts used routinely for mosquito control: 1 pound per acre in early spring, and lesser amounts later as needed. By such application the nearly insoluble DDT is distributed in a thin layer on the pond bottom. Three similar ponds which were not treated with DDT during the 11-week study period served as controls. However, all six ponds had been treated with DDT in one or both of the two preceding years.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1963)92[211:POPAAR]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1963

数据来源: Taylor

摘要:

Bottom fauna and plankton populations at two physically similar locations on the Montreal River, Saskatchewan, were compared. Filter-feeding Trichoptera larvae were more abundant at the station below a series of productive lakes. This difference was related to the richer supply of suspended food in the water, rather than to differences in alkalinity. Ephemeroptera and Plecoptera distributions are also discussed.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1963)92[216:FIDAPF]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1963

数据来源: Taylor

摘要:

Walleye (Stizostedion vitreum vitreum) eggs were incubated in a temporary jar hatchery using Rainy River water taken below paper mills discharging sulfite, kraft, insulating board, and groundwood wastes. Eggs were also incubated in trays held on and off the bottom in the river below mills, above the mills, and in tributary streams. In two years, survival of eggs in jar controls was 31.2 to 73.5 percent. Survival to hatching of eggs jar-incubated in polluted water was 0.02 to 6.0 percent. At river stations below mills survival of tray eggs on bottom did not exceed 1.2 percent; and off bottom, 3.5 percent. Eggs held on bottom above mills had maximum survival of 37.6 percent; and off bottom, 49.1 percent. In most experiments in polluted Rainy River water the principal cause of mortality was Sphaerotilus growths on the eggs which prevented successful emergence of fry. Prior to hatching, egg-survival rate in jars was similar in controls and in experiments. Chemical treatment to remove slime increased hatch of eggs. Sphaerotilus-covered eggs removed to fresh water lost the bacterium and hatched at a high rate. Some bottom deposits below mills were toxic to eggs.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1963)92[220:SOWEIR]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1963

数据来源: Taylor

摘要:

Three stockings of marked, catchable-sized, warmwater fishes were made in a 30-acre lake. Creel censuses were then conducted to determine the percent recapture of these fish and their contribution to the anglers' catches. The percent returns from the spring stockings during the year in which the fish were stocked were similar for the three principal kinds of fishes, namely: crappies, 32.0 percent; bullheads, 28.3 percent; and bluegill, 26.1 percent. Further returns from these stockings during the following year averaged only 2.5 percent. As compared to returns from the spring stockings, very poor returns resulted from a fall stocking subjected to fishing the following season. The overall return in this case was only 8.6 percent.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1963)92[235:ROSCWF]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1963

数据来源: Taylor

摘要:

In an unusually large fishery for paddlefish, Polyodon spathula (Walbaum), anglers took 8,210 to 4,920 paddlefish by snagging during the March 15-May 15 seasons of 1958-61 in the Osage River and Lake of the Ozarks, Missouri. Large fish caught averaged 33 pounds in 1958, and their average weight increased annually to 38 pounds in 1961. Most of those caught in 1959 were 11 to 21 years old, with some 27 to 30. Small fish began entering the harvest in 1959 and averaged 1.6 pounds that year, 3.5 pounds in 1960, and 4.3 pounds in 1961. These young fish were 2 to 4 years old in 1959. Total weight harvested varied from 70 to 107 tons annually.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1963)92[239:TPFOTO]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1963

数据来源: Taylor

摘要:

Stomachs were examined from 1,469 Lake Michigan bloaters, Coregonus \[Leucichthys]\ hoyi, greater than 7 inches long which contained identifiable food. An additional 461 ciscoes less than 7 inches long were incorporated into the study; these latter fish were not positively identified, but most of them undoubtedly were bloaters. The specimens were caught in bottom nets except for 49, all less than 6 inches long, taken in midwater trawls.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1963)92[245:FOTBCH]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1963

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/1548-8659(1963)92[257:SOFFPI]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1963

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/1548-8659(1963)92[258:EF]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1963

数据来源: Taylor