摘要:

This paper describes the behavior of sockeye salmon fry (Oncorhynchus nerka) during their migration from stream spawning gravels to lake nursery areas. Fry were negatively phototactic, sought holding areas along stream banks during daylight hours, and only left holding areas and gravel to migrate during the darkest hours of the night. Fry migrated as individuals, facing downstream, and usually exhibited swimming movements. Certain features of the migratory behavior are discussed in terms of survival values in the face of intense piscivorous predation.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1962)91[133:SABOSS]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

In the spring of 1959 two wild stocks and a domesticated stock of brook trout were planted as fingerlings in Bear Pond in the northern Adirondack Mountains of New York. A resident population of brook trout of domesticated parentage was also present. Differences in behavior between the four groups affected the catch by angling and trap-netting. During the summer of 1960, when all four groups were approximately the same length, over 30 percent of the domesticated stocks were taken by fly fishing, while during the same period only 12 percent of the two wild stocks were recovered. The stocked domestic group was found to be much more vulnerable to trap-netting than the other groups. During the first 24 hours of netting, 46 percent of the trout estimated at large from this stock were recovered. At the end of three weeks of trap-netting, 84 percent of the stocked domestic, 64 percent of the resident domestic, 66 percent of the Long Pond Stream wild, and 44 percent of the Honnedaga Lake wild brook trout were recovered. Gill-netting was not found to be selective for any of the four groups.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1962)91[140:PISWAD]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

Four experiments with marked, legal-sized, hatchery-reared, brown and rainbow trout were conducted on portions of five Michigan trout streams to determine which season of release would yield the greatest return to the angler. Equal numbers of tagged or fin-clipped fish were planted in the fall after the close of the trout season and in the spring before the trout season opened. In two experiments, larger numbers of fish were also released during the fishing season; May, June, and July. In three of the experiments, angler returns were obtained by voluntary reports and by partial creel census conducted during the first season that marked fish were present. In the fourth experiment, all recoveries were reported voluntarily. Almost 63,000 fish were planted, and recaptures of 1,173 brown trout and 2,307 rainbow trout were reported. In six tests with rainbow trout and four tests with brown trout, spring planting yielded significantly higher returns than did fall planting. In two tests with brown trout, spring planting yielded higher returns, but its superiority over fall planting was not statistically significant.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1962)91[145:RBAOLT]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

The Aquatic Sciences Information Retrieval Center is being developed to meet the urgent necessity for rapid synthesis and dissemination of information related to the aquatic sciences. The inability of researchers to maintain familiarity with recent work in their discipline is looming as one of the most significant problems in many fields of endeavor, including fisheries and related aquatic sciences. Further rapid progress in the aquatic sciences is believed to be contingent upon an objective means of relieving this problem.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1962)91[151:ADASIR]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

Juvenile coho salmon, Oncorhynchus kisutch (Walbaum), were held at 20° C. in 12-gallon bottles, usually 10 to a bottle, in continuously renewed fresh water having various dissolved oxygen concentrations. Reduced oxygen concentrations were maintained by bubbling nitrogen through the inflowing water. In most of the experiments, the fish were fed beach hoppers (marine amphipods) to repletion twice daily so that food was available for 10 hours each day. Growth and food consumption rates of age-class 0 juveniles observed in the year 1956 declined slightly with reduction of oxygen concentration from a mean of about 8.3 to 6 and 5 mg/l, and declined more sharply with further reduction of oxygen concentration. Weight gains in grams per gram of food consumed (food conversion ratios) were slightly depressed at concentrations near 4 mg/l, and were markedly reduced at lower concentrations. At concentrations averaging 2.1 to 2.3 mg/l, many fish died and surviving fish consumed very little food and lost weight, although some food was assimilated. Interesting seasonal variations were noted of the dissolved oxygen requirements of coho salmon, their food and oxygen consumption rates, and their gross food conversion efficiencies. The conversion efficiencies apparently increased, whereas food consumption rates declined in the fall of 1956. The seasonal variations are not ascribable entirely to size differences. Very poor growth and low food consumption rates at reduced oxygen concentrations near 4 and 5 mg/l and unexpected mortalities at lower concentrations near 3 mg/l observed in the summer of 1955 probably were due to synergistic action of a toxicant leached from rubber (latex) tubing supplying water to the test vessels. The stated results of 1956 tests were not likewise invalidated.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1962)91[155:IOOCOT]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

Lack of suitable conditions for natural spawning is a limiting factor in brook trout production in waters in the Adirondack Mountains, New York. Presence of ground water or springs is considered a major requirement for successful spawning in this species. Two kinds of improved spawning areas have been offered: (1) replacement of unsuitable bottom material with gravel on or near known natural spawning areas; (2) piping and dispersing water through a gravel-filled box. Both types of improvements have been used by brook trout under some conditions. Further studies are required to determine factors responsible for acceptance or rejection of improved areas and to evaluate efficiency in the production of fry.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1962)91[168:ASFFBT]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

Bioassays were conducted with thirteen organic phosphorus insecticides to determine their relative toxicity to four species of fish. An extremely wide range in toxicity was found with 96-hour TLm(median tolerance limit) values ranging from 0.0052 to 610 p.p.m. Bluegills were generally the most sensitive fish, followed by guppies, fathead minnows, and then goldfish. The maximum sensitivity of the different species to particular compounds ranged from 4 to as high as 900 times the minimum. Additional experiments were conducted with some of the compounds. Larger bluegills (10 grams) were slightly more tolerant than smaller bluegills (2 grams) to Delnav, parathion, and malathion; green sunfish of similar size and largemouth bass (5 grams) were not greatly different in sensitivity from the larger bluegills. Tests of five compounds revealed that the toxicity of emulsible concentrates or wettable powders was similar to that of the technical grade material. Fathead minnow fry from 2 to 30 days old were about ten times as sensitive to Delnav as adults. However, when exposed to TEPP there was little difference in sensitivity between the fry and adults. During exposure for 15 days the toxic effect of Delnav increased about fivefold over that shown in 96 hours, but there was no additional fish mortality between 15 and 30 days.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1962)91[175:TTOOPI]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

Thirteen dams, twelve deflectors, and several covers were constructed in a 450-yard section of Hayes Brook, Prince Edward Island, to create suitable hiding places for brook trout, Salvelinus fontinalis (Mitchill). In the following year the standing crop of fingerlings (age 0) was above average. The numbers of age I and older trout were approximately doubled. The alterations had no noticeable effect on the growth of trout.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1962)91[185:PAOSHT]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

Field studies using tagging and recapture techniques with displaced fish were employed to demonstrate a significant exchange of winter flounder, Pseudopleuronectes americanus, between two areas of Narragansett Bay separated by a natural constriction and earth sill. The tagging studies also provided information on movement, exploitation rates, and sex ratios of the winter flounder. A mathematical model derived from the heat diffusion equation was utilized to suggest that a relatively short search time would be required by winter flounder to locate a hurricane-barrier opening when empirical values for model parameters were utilized. It is concluded from the tagging studies and from theoretical considerations that the proposed hurricane protection devices will not act as physical barriers to fishes which use the bay for spawning or feeding.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1962)91[189:PHBRTW]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

Diallel crosses were made among Coregonus clupeaformis (Mitchill), Leucichthys artedii LeSueur and Prosopium cylindraceum (Pallas). Embryos of the crosses Coregonus ♂ X Leucichthys ♀, Coregonus ♂ X Prosopium ♀, and Leucichthys ♂ X Coregonus ♀ completed development and hatched. This is the first known instance of successful hybridization between the genera Coregonus and Prosopium. Embryos of crosses Leucichthys ♂ X Prosopium ♀, Prosopium ♂ X Coregonus ♀, and Prosopium ♂ X Leucichthys ♀ passed through a considerable portion of their development, but all died prior to the expected time of hatching. Embryos of these three crosses were invariably deformed.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1962)91[196:EHATCF]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor