摘要:

The effect of elevated temperature on early embryonic development of tautog, Tautoga onitis, was the subject of a study in which both spawning adults and developing eggs were exposed to similar temperatures. When incubation temperature was gradually raised from 20.0 C, anatomical deformities, including stunted embryos and/or abnormal body curvatures, as well as increased mortality occurred between 24.2 and 26.3 C. Normal development was evident after the temperature returned to 20.0 C.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1978)107<820:EOETOE>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Acute toxicity tests were conducted on permethrin (Pounce(R)), a synthetic pyrethroid, by using 8-12- and 20-30-mm Louisiana red swamp crayfish (Procambarus clarkii), fry channel catfish (Ictalurus punctatus), fingerling largemouth bass (Micropterus salmoides), mosquitofish (Gambusia affinis), and bullfrog tadpoles (Rana catesbeiana). The 96-h LC50 values were 0.39, 0.62, 1.1, 8.5, 15.0, and 7,033 μg/liter, respectively.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1978)107<825:ATOPTS>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

This chronic zinc toxicity test with sockeye salmon (Oncorhynchus nerka) consisted of a 3-mo adult exposure followed by an 18-mo exposure of embryonic through smolt stages. The zinc concentrations utilized were 30 to 112 μg/liter during the adult-to-smolt exposure period, and an additional 242 μg/liter concentration was used for the embryo-to-smolt exposure period. These zinc concentrations produced no adverse effects on survival, fertility, fecundity, growth, or on the subsequent survival of smolts transferred to seawater. Exposure to 242 μg/liter produced sufficient acclimation to markedly decrease acute mortality at zinc levels lethal to unacclimated sockeye salmon juveniles. The 112- and 242-μg/liter concentrations were 0.15 and 0.32, respectively, of the 749-μg/liter, 96-h LC50 for the 8-mo-old sockeye salmon. An application factor relating 96-h LC50 and “safe” concentrations of zinc to anadromous sockeye salmon in soft water appears to be >0.15 and at least 15 times larger than the often recommended 0.01 application factor for zinc based on studies with other species.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1978)107<828:EOCZEO>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Flow-through acute toxicity tests of cadmium, copper, and zinc were conducted with adult male coho salmon (Oncorhynchus kisutch) and adult male steelhead (Salmo gairdneri). The 96-h LC50 values for copper were 46 and 57 μg/liter, and for zinc were 905 and 1,755 μg/liter, for coho salmon and steelhead, respectively. Mortality induced by cadmium was slow in onset, but 50% mortality occurred after more than a week at 3.7 μg/liter for coho salmon and 5.2 μg/liter for steelhead. Hardness and alkalinity of the water supply were higher during the toxicity tests with steelhead, complicating direct comparisons between the two species.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1978)107<837:ALLOCC>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Continuous-flow toxicity tests were conducted to determine the relative tolerances of newly hatched alevins, swim-up alevins, parr, and smolts of chinook salmon (Oncorhynchus tshawytscha) and steelhead (Salmo gairdneri) to cadmium, copper, and zinc. Newly hatched alevins were much more tolerant to cadmium and, to a lesser extent, to zinc than were later juvenile forms. However, the later progression from swim-up alevin, through parr, to smolt was accompanied by a slight increase in metal tolerance. The 96-h LC50 values for all four life stages ranged from 1.0 to >27 μg Cd/liter, 17 to 38 μg Cu/liter, and 93 to 815 μg Zn/liter. Steelhead were consistently more sensitive to these metals than were chinook salmon. When a sensitive life stage for acute toxicity tests with metals is sought, the more resistant newly hatched alevins should be avoided. Although tolerance may increase with age, all later juvenile life stages are more sensitive and should give similar results.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1978)107<841:TOCCAZ>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The possibility of in vivo conversion of inorganic mercury to MeHg in brook trout (Salvelinus fontinalis) was tested by chronically exposing fish to mercury (from Hg(NO3)2) at a concentration of 1 ng/ml, for 56 days, and then maintaining them at background levels for 294 days. The concentrations of inorganic and methylated mercury (MeHg) in several organs of control and test fish were periodically measured over this 50-wk period. The inorganic mercury levels in test fish increased rapidly during exposure. The MeHg concentrations in both control and test fish increased slowly and at the same rate, with final 350-day concentrations comparable to levels found in wild brook trout from an uncontaminated area. This information indicates that fish do not methylate inorganic mercury in vivo, and that approximately one-half of the MeHg body burdens in the fish was acquired via the food.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1978)107<848:MMIBTS>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Rainbow trout accumulated methylmercury linearly during 24 days when continually exposed to methylmercury. Exposure was by means of water solutions (0.07-1.33 μg Hg/liter), food consumption (8.0-380.5 ng Hg/g fish per day) or both. Methylmercury accumulated from one source had no influence on the rate of uptake from the second source. Methylmercury accumulated from both sources was quantitatively additive, which validates a frequently used assumption. Food consumption rate and therefore growth rate had no influence on the rate of mercury accumulation from water. Nearly 70% of the methylmercury ingested and 10% of the methylmercury passed over the gills was assimilated.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1978)107<853:TRCOMF>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Studies on the elemental composition of bluegills and other freshwater fish revealed that fish differ in concentrations of calcium, magnesium, potassium, sodium, nitrogen, phosphorus, sulfur, and ash depending upon species, size, and collecting site. For rigorous considerations of the elemental composition of fish in a body of water, fish of different species and sizes must be collected and analyzed. Nevertheless, for many ecological purposes, the variation in elemental concentrations was not too large to prevent generalizations from data presented in this study.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1978)107<862:COSEAA>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/1548-8659(1978)107<868:ROBCTL>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/00028487.1978.10493163

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor