Predicting Year-class Abundance of Yellowstone Lake Cutthroat Trout
Author: Ross V. Bulkley
Publisher:
Published: 1962
Total Pages: 21
ISBN-13:
DOWNLOAD EBOOKRead and Download eBook Full
Author: Ross V. Bulkley
Publisher:
Published: 1962
Total Pages: 21
ISBN-13:
DOWNLOAD EBOOKAuthor: Ross V. Bulkley
Publisher:
Published: 1962
Total Pages: 32
ISBN-13:
DOWNLOAD EBOOKFluctuations in strength of year classes from 1945 to 1956 of Yellowstone Lake cutthroat from Pelican and Chipmunk Creeks are compared with the parental stock and several climatically influenced factors of the environment. Variations in year-class strength in the two tributaries were highly correlated with fluctuations in lake water levels. Strong year classes occurred in yeas of low water. Female spawner escapement, timing of the runs, and summer air temperatures were not significant factors. A formula based on water levels is presented for predicting year-class strength in Pelican Creek and in the Fishing Bridge area fishery. Stocking of fry in years of high water is suggested as a means of supplementing natural production. A method of forecasting lake water levels several months in advance of their occurrence is discussed.
Author:
Publisher:
Published: 1962
Total Pages: 21
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DOWNLOAD EBOOKAuthor: Norman Gustaf Benson
Publisher:
Published: 1963
Total Pages: 52
ISBN-13:
DOWNLOAD EBOOKEquilibrium yield of the cutthroat trout, Salmo clarki lewisi Girard, in Yellowstone Lake, Wyo., is determined from data on catch and spawning runs from 1945 to 1961. Changes in growth rate, spawning runs, mortality rates, and year-class strength are related to differences in total catch. Three stages of exploitation of the stock are defined and the maximum safe catch or equilibrium yield is estimated at 325,000 trout. Management of the sport fishery according to equilibrium yield is discussed with reference to regulations, distribution of fishing pressure, planting, and interspecific competition. The Yellowstone River fishery is treated briefly.
Author: U.S. Fish and Wildlife Service
Publisher:
Published: 1964
Total Pages: 652
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DOWNLOAD EBOOKAuthor: United States. Bureau of Sport Fisheries and Wildlife
Publisher:
Published: 1941
Total Pages: 32
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DOWNLOAD EBOOKAuthor: Roger E. Burrows
Publisher:
Published: 1964
Total Pages: 20
ISBN-13:
DOWNLOAD EBOOKIn experiments at the Bureau's Salmon-Cultural Laboratory, to determine the excretory products of significance in rearing ponds and the possible effect of these products on fingerling chinook salmon (Oncorhynchus tshawytscha), the results demonstrated that ammonia and urea are the principal products. The relative amounts of these products vary with the concentration of fish and with their metabolic activity. Ammonia assumes dominance in an unfavorable environment. Water temperature, pH, and pond type affect the toxicity of ammonia solutions. Continuous exposure to levels of ammonia normally encountered in rearing ponds produced extensive hyperplasia of the gill epithelium in controlled experiments.
Author: Allan E. Thomas
Publisher:
Published: 1964
Total Pages: 24
ISBN-13:
DOWNLOAD EBOOKA stamina tunnel was developed to measure differences in physical performance of salmonid fingerlings. By subjecting fish samples to controlled patterns of water velocity, it has proved possible to demonstrate differences in fish stamina imparted by disease, nutrition, and environment.
Author: W. G. Smith
Publisher:
Published: 1970
Total Pages: 32
ISBN-13:
DOWNLOAD EBOOKSummer flounder eggs and larvae are described from artificially fertilized specimens and from material collected at sea, accompanied by a set of illustrative plates.