Food Habits of Five Centrarchids During Filling of Beaver Reservoir, 1965-66
Food Habits of Five Centrarchids During Filling of Beaver Reservoir, 1965-66

Author: James W. Mullan

Publisher:

Published: 1970

Total Pages: 16

ISBN-13:

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Stomach contents were examined from 1,886 largemouth bass, 334 spotted bass, 1,689 bluegills, 918 green sunfish, and 579 longear sunfish from the shoreline areas of Beaver Reservoir during two of the first three years of filling. Quality and quantity of food by seasons and size is related to abundance of the principal forage. Greatest volume of food were found in winter-spring months when water level rose and inudated soils for the first time; terrestrial earthworms, insects, slugs, spiders, centipedes, sowbugs, and work snakes were major foods in these seasons, particularly for fish of 101-200 mm in total length. Except for the larger bass, fish had smallest volumes in stomachs in later fall, following the decline that began when water levels stabilized in June.

Clinical Methods for the Assessment of the Effects of Environmental Stress on Fish Health
Clinical Methods for the Assessment of the Effects of Environmental Stress on Fish Health

Author: Gary A. Wedemeyer

Publisher:

Published: 1977

Total Pages: 24

ISBN-13:

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Clinical methods are presented for biological monitoring of hatchery and native fish populations to assess the effects of environmental stress on fish health. The choice of methods is based on the experience of the authors and the judgment of colleagues at fishery laboratories of the U.S. Fish and Wildlife Service. Detailed analysis methods, together with guidelines for sample collection and for the intrepretation of results, are given for tests on blood (cell counts, chloride, cholesterol, clotting time, cortisol, glucose, hematocrit, hemoglobin, lactic acid, methemoglobin, osmolality, and total protein); water (ammonia and nitrate content); and liver and muscle (glycogen content).

Acrolein, Dalapon, Dichlobenil, Diquat, and Endothal
Acrolein, Dalapon, Dichlobenil, Diquat, and Endothal

Author: Leroy C. Folmar

Publisher:

Published: 1977

Total Pages: 24

ISBN-13:

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Toxicity tables for the herbicides acrolein, dalapon, dichlobenil, diquat, and endothal list the test organisms, types of tests, experimental conditions, and test results. Each table is followed by a list of references. The materials provide a useful source of toxicity data on these herbicides to researchers, regulatory agencies, and manufacturers.

Biology of the Redtail Surfperch (Amphistichus Rhodoterus) from the Central Oregon Coast
Biology of the Redtail Surfperch (Amphistichus Rhodoterus) from the Central Oregon Coast

Author: Donald E. Bennett

Publisher:

Published: 1977

Total Pages: 32

ISBN-13:

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Data on certain aspects of the life history of the redtail surfperch were collected along the central coast of Oregon, from April 1967 through April 1969. Annulus formation occured during February through June, usually earlier in young than in older fish. Mating occurred from late December to early January, and the young were born from July through September. The number of embryos per female ranged from 1 to 39 (mean 13.3) and increased linearly with the length and weight of the females. Food of the fish from the surf zone included crustaceans (by far the most important group in both frequency of occurrence and total volume) and (in order of decreasing importance) fishes, mollusks, and polychaetes. Parasites of the redtail surfperch were immature nematodes (Anisakinae) ; the digenetic trematode Genitocotyle acirra; the monogenetic trematode, Diclidophora sp.; and the copepods, Caligus sp., Clavella sp., and Argulus catostomi.