摘要:

Samples of three species of Indian carp, Catla catla, Cirrhina mrigala, and Labeo rohita, were examined when they were 480 days old by biochemical tests and electrophoresis of the blood and plasma. The three species did not differ significantly in total plasma protein (micro-Kjeldahl), relative amounts of total plasma protein and total lipoprotein, and plasma albumin. Significant differences were found in body weight, blood sugar, α1-, α2-, β-, and γ-globulin fractions from the plasma, and lipoprotein fractions. Electrophoretic studies revealed two qualitatively different components: a second hemoglobin band in Catla catla, and a third lipoprotein fraction designated αFin Cirrhina mrigala. The three species were found to differ significantly when weight, blood sugar, α1-, α2-, β-, and γ-globulin fractions from the plasma were considered simultaneously.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1961)90[1:CSOTBB]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

False annuli were found in 65 to 90 percent of brook trout (Salvelinus fontinalis) specimens of several year classes sampled in four Adirondack lakes. Maximum age of fish present was known since all four lakes were recently reclaimed. One or two false annuli were found on scales of trout planted as advanced fry or hatched from eggs deposited naturally. A method of identifying accessory checks based on scale measurements was developed for determining age of these trout. Influence of environmental temperature on growth rate is discussed as a possible explanation for formation of false annuli.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1961)90[6:ROOFAI]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

During studies of Atlantic coast striped bass, Roccus saxatilis (Walbaum), by the U. S. Fish and Wildlife Service and co-operators from 1955 to 1959, 478 large fish ranging in weight from 6 to 54 pounds and in age from 3 to 18 years were tagged. Tagging locations were the North Carolina coast, where 81 fish were tagged; Albemarle Sound and Roanoke River, North Carolina, where 97 fish were tagged; and Chesapeake Bay and tributaries, where 300 tags were applied. Catches by commercial and sport fisheries indicated that large striped bass concentrated on the coast of North Carolina in late fall and winter, on or near spawning areas for striped bass in North Carolina and Chesapeake Bay in late winter and spring, and along the coast north of Chesapeake Bay as far as Massachusetts in the summer and fall. Recaptures were made of 19 fish tagged on the North Carolina coast; 23 tagged in Albemarle Sound and the Roanoke River, North Carolina; 27 tagged in Chesapeake Bay and its tributaries; and 1 tagged in the Thames River, Connecticut. Some fish were recaptured near the tagging location but most of them migrated along the coast and were caught in other concentration areas during the season of greatest fishing pressure.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1961)90[13:ACMOLS]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

To predict possible effects of the dams and gates of the proposed Passamaquoddy Tidal Power Project on herring movement in and out of the Passamaquoddy Bay region, information was first needed on the swimming performance of the fish. Maximum and sustained swimming speed tests designed for this purpose indicated (1) that the maximum swimming speed for herring 60 to 219 millimeters long ranged from 2.3 to 4.4 feet per second, and (2) that the swimming endurance (length of time a fish was able to swim in a particular water velocity) for herring of similar lengths exposed to water velocities of 1.2 to 3.2 feet per second ranged from 1 to 115 minutes. If the fish responds in the field as in the laboratory, the filling gates that operate at flood tide and emptying gates that operate at ebb tide would not appear to prevent migration.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1961)90[21:SSOIAH]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

Priest and Upper Priest Lakes located in northern Idaho produced a catch of approximately 100,000 fish in 1956. The catch was composed of kokanee (93 percent), cutthroat trout (5 percent), and Dolly Varden and lake trout (2 percent). Three out of four fishermen were nonresidents, and a third of the hours fished were expended by anglers from more than 600 private cabins. The average rate of catch for kokanee was 2.5 fish per boat per hour on Priest Lake and 0.9 on Upper Priest Lake; for cutthroat trout it was 1.0 fish per boat per hour on the upper lake and 0.7 on Priest Lake. Juvenile cutthroat trout were found to spend 2 to 3 years in tributary streams before entering the lakes. The catch and spawning escapements of kokanee from Priest Lake during 1955 and 1956 were composed chiefly of fish in their fifth year of life.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1961)90[27:HASAGO]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

Pigment analyses have been made of a lagoon emptying into the Gulf of Mexico. This water showed a typical cycle of early spring flowering, later spring minimum, summer oscillations, and a secondary early fall maximum. The cycle resembled those of more northern waters, but the blooms in East Lagoon occurred earlier in the year. The bloom periods were related to various physical factors—solar radiation, temperature, and rainfall—with a direct relationship between incident radiation and chlorophyll a production indicated for the fall of 1957. The chlorophyll production of the lagoon compared favorably with other waters in these latitudes, yielding a mean of 17.6 mg chlorophyll a/m3during the sampling period from October 1957 to May 1959. An analysis of the precision of the method indicated a standard error of 0.565 ± 0.085 mg/m3for chlorophyll a and 1.35 ± 0.165 MSPU/m3for chlorophyll c. The large value for the latter pigment is attributed to the method of calculation.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1961)90[32:PPIELG]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

Egg production and egg survival of the American smelt, Osmerus mordax (Mitchill), were studied during the 1958 spawning run at Dean Brook, Ellsworth, Maine. The construction, number, and location of sampling units utilized in the estimate of egg production and egg survival are discussed. Egg production was 13,726,351 ± 3,525,971 and egg survival was 3,423,177 ± 610,384. Regressions of egg density and egg survival upon distance above the stream mouth are computed. An index of spawning activity could not be related to observed environmental variables. A density of smelt eggs for hypothetical maximum prolarval production was 11,745 eggs per square foot. Maximum prolarval production occurred in regions of moderate smelt egg deposition. Sources of egg mortality are noted and a nonstatistical estimate of prolarval production is presented: 75,440. A total egg mortality of 99.5 percent is indicated.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1961)90[42:PASOEO]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

Use of radioisotopes has increased rapidly in hydrobiology and fish culture. Their use, especially P32, to study circulation of nutrients has been demonstrated and offers opportunities in problems of lake metabolism. The most extensive use of isotopes has been to determine photosynthetic activity in plankton through C14uptake. Applications and limitations are discussed. Isotopes have been successfully used in food studies of fish to determine food selection, metabolism, and storage. Water movements in fresh and salt water and in sewage problems have been successfully followed by use of various isotopes. Marking of aquatic animals with radioisotopes has many possible applications, but has been little used because of some inherent problems related to danger to organisms and in field use. Extent of future use of isotopes in hydrobiology will be determined by further study of hazards and public acceptance of field studies.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1961)90[49:UORIHA]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

A 3-year study was conducted to determine mortality rates for downstream migrant salmonids passing through spillways or turbines at McNary Dam. Mortalities were determined by releasing marked fish into the exit under study (spillway or turbine) and marked control groups immediately below the dam. Samples of released fish were recovered at stations below the dam, and survival rates were computed from the ratio of the number of experimental to control recoveries. Detailed techniques were devised to test assumptions involved in the estimating procedure. In 1955 and 1956 estimates were obtained for fingerling chinook salmon (Oncorhynchus tshawytscha) at McNary Dam. In 1957 yearling chinook were tested at Big Cliff Dam, a structure on the Santiam River with a turbine and spillway similar to those at McNary Dam. As a control measure, fingerling chinook were also tested in 1957. In all experiments the turbine was the major source of mortality. For each exit, no significant difference was found between mortalities at McNary Dam and Big Cliff Dam on fingerling chinook or between mortality rates for fingerling and yearling chinook. Estimated mortality rate of salmon passing over the spillway was 2 percent with a 95 percent confidence interval from 0 to 4 percent. Estimated mortality of salmon passing through the turbines was 11 percent with a confidence interval from 9 to 13 percent. The consistency of the results of the studies indicated that the estimates were valid representations of the mortalities experienced under the tested conditions.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1961)90[58:MODMSA]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor

摘要:

Both the transforming ammocoete and parasitic Petromyzon marinus display an endogenous cyclic activity rhythm. The rhythm is gradually lost in constant conditions of dim light but is re-established by exposing the animal to one or two artificial diurnal light cycles. The period of the endogenous cycle in one larva was 22 hours 58 minutes. Rhythm in the parasite can also be re-established by exposing the animal during a single short period to chemical sensory stimulation produced by the scent of fish. Diurnal rhythm so established was maintained during a period of 5 days at the end of which the observations ceased. Sensory stimulation can function as a “setting” mechanism of the physiological clock. In this instance the setting mechanism is not related to the metabolism of the animal but must have its seat in the central nervous system.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1961)90[73:DPITAO]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1961

数据来源: Taylor