摘要:

Laboratory experiments were conducted to measure uptake of fission products by fish from water and from oral doses. Availability of fission products to the fish was curtailed considerably by the formation and settling of radioactive particles in the water and by sorption to abiotic surfaces. Spot, Leiostomus xanthurus, and Atlantic croaker, Micropogon undulatus, accumulated relatively low levels of radioactive material from seawater. Following a single oral dose, croaker assimilated a maximum of 14% in 4 hours, but 94% of the original dose was eliminated after 4 days. Bluefish, Pomatomus saltatrix, assimilated only 3% of the cumulative dose of mixed fission products administered in shrimp meat on alternate days for 55 days. Of the amount assimilated from oral doses by croaker and bluefish, the largest concentrations were found in the internal organs.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1966)95[145:UOMFPB]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

Adult northern puffers, Sphaeroides maculatus, were exposed to graded concentrations of endrin, a chlorinated hydrocarbon insecticide, at 20 C, 24‰ salinity, and pH 8.0. All animals subjected to 10.0 ppb of endrin died within 24 hours. At concentrations of 1.0 ppb of endrin, or lower, no mortality occurred within 96 hours.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1966)95[153:EOEOBA]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

A decline of the sport fishery for salmon has been associated with the application of DDT to control human insect pests around the shores of Sebago Lake. The average DDT contents of 10-salmon samples collected in 1962, 1963, and 1964 were 1.1, 3.2, and 1.8 ppm by total wet weight. Salmon belonging to age group III had average DDT contents of 1.2 ppm; age group IV, 8.0 ppm; and age group V, 8.8 ppm. Ovaries of III-year-old salmon had 0.87 ppm of DDT, while ovaries from IV- and V-year-olds had 6.0 ppm DDT. Data also include results of DDE assays and calculated DDT concentrations in the fat. DDT concentrations found in small samples of lake chubs, common shiners, smallmouth bass, American smelt, lake white-fish, and brook trout are also reported.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1966)95[160:CODILS]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

Laboratory bioassays were conducted with some chlorinated hydrocarbon insecticides, organophosphate insecticides, other insecticides and acaricides, and with herbicides to determine their relative toxicities and immobilization values for two species of daphnids, Daphnia pulex and Simocephalus serrulatus. Both species are satisfactory bioassay organisms for the determination of a wide variety of pesticides, with D. pulex being the more sensitive.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1966)95[165:TOSPTT]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

Blood characteristics and mortality were compared between rainbow trout which were captured by (1) angling with artificial lures, (2) electroshocking, and (3) seining. The hemoglobin concentration, erythrocyte sizes, plasma protein concentrations, and plasma protein fractions varied according to the method of capture. Mortality was negligible in the shocked and seined lots, but was above 85% in the hooked fish group. Mortality was delayed and the symptoms suggest progressive shock. Definite differences in behavior were noticed in the postcapture fish and included prolonged fasting (shocked and hooked fish), hyperexcitability (shocked fish), and lethargy (hooked fish). The authors believe that presently used methods of capturing and handling fish should be re-evaluated, particularly if the fish are to be used in toxicological or management studies.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1966)95[170:IOCMOB]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

Radiographs of vertebral structures of 10,377 sockeye, 4,403 chum, and 4,777 pink salmon collected in 1958 to 1962 were examined to determine the frequency of occurrence of abnormal vertebrae in wild populations of mature Pacific salmon. Various types of deviations from the orderly processes of development or segmentation that resulted in abnormal structures were classified as fusions or abnormalities. The frequency of occurrence of abnormalities in the vertebral column was tabulated by species, sampling locations, and year of sampling. Abnormalities were found in the vertebral columns of 2.8% of the sockeye, 3.3% of the pink, and 2.9% of the chum salmon. Differences in frequency of occurrence of abnormalities among the species were not statistically significant. In sockeye salmon, 47% of the abnormalities were in the caudal region and 42% in the abdominal region; in pink salmon, 39% were in the caudal and 49% in the abdominal region.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1966)95[177:VAISPA]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

Fall-chinook salmon eggs in Abernathy incubation channel suffered as much as 85% mortality when 15 to 30% of the voids in the gravel beds were filled with sediment. With one 70-foot section of the channel used as a silt-settling basin, the mortality was reduced to 10% or less. We believe that a siltation control system consisting of a flushable sand trap and settling basin constitute the most economical means of reducing the amount of sediment entering this and similar channels.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1966)95[183:SAESII]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

Studies to show whether pink salmon (Oncorhynchus gorbuscha, Walbaum) will repeat their original choice of spawning area when captured and transported to another location were done in Olsen Creek, Prince William Sound, Alaska, in 1961, 1962, and 1963. Fish to be displaced were anesthetized with MS-222 (except in 1961 when no anesthesia was used) and marked with Petersen disk tags. Equal numbers of control fish were treated in an identical manner and left at the donor site.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1966)95[188:BODAPS]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

The periodicity, incidence, and intensity of infection of the hemoflagellate Cryptobia salmositica Katz, 1951, in freshwater fishes corresponds to the biological association between teleost hosts and rhynchobdellid vector: adult and young coho salmon (Oncorhynchus kisutch), the torrent sculpin (Cottus rhotheus), and the salmonid leech (Piscicola salmositica). Adult salmon and leeches occupy Soos Creek, a western Washington stream, only during the fall and winter months. The incidence and intensities of Cryptobia in the maturing salmon increase in response to the period that feeding and infected leeches are carried, and ultimately 80 to 100% of the spawning population acquire the parasites. Young cohos also become infected during the fall and winter, but the incidence is generally less than 5%; the overwintering fingerling population, including the few infected young, emigrates seaward in the spring. The incidence of Cryptobia in the resident sculpin population averages 60%, but significantly lower incidence and higher intensities occur in young fish, those less than 65 mm in length; the sculpins serve as reservoirs of Cryptobia in the study stream.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1966)95[196:HROCSP]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

Five hundred ten measurements of swimming speeds of skipjack tuna (Euthynnus pelamis) from four schools and 33 of yellowfin tuna (Thunnus albacares) from one school were made from underwater motion-picture records obtained at sea. The relation of swimming speed to rate of tail beats is described for yellowfin averaging 51.9 cm long and for skipjack averaging 57.2 cm long. At similar rates of tail beats, yellowfin swam faster than skipjack when speed was measured in body lengths per second. Variations in the mean swimming speed of the schools of feeding skipjack were unrelated to body length. The difference between the swimming speeds of tunas observed during this study, which ranged from 0.5 to 14.4 body lengths per second (0.3 to 6.9 m per second), and higher speeds previously reported for tunas is discussed.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1966)95[203:SSOYAS]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor