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The Life History and Contributions to the Ecology of Camelobaetidius variabilis Wiersema 1998 (Ephemeroptera: Baetidae) in Honey Creek, Oklahoma

Description: A study of the life history and ecology of Camelobaetidius variabilis was conducted in Honey Creek, OK from February 2003-April 2004. Nymph development was assessed using changes in external morphology. Laboratory reared nymphs were used to calculate number of degree days to complete development (772 degree days at 20.8° C ±.38° C), which was used to determine voltinism. Field collected nymph microhabitat distribution was used in assessing microhabitat distribution. Nymphal thermoregulation was assessed during the winter and spring by comparing nymphal numbers present in shaded and un-shaded habitats. Camelobaetidius variabilis nymphs showed preference for algal microhabitats during the spring and leaf packs in the winter. Nymphs inhabited leaf packs to increase metabolic rate during the winter. Increased temperatures aid in development of nymphs. Camelobaetidius variabilis exhibited a multivoltine life cycle with six overlapping generations.
Date: December 2005
Creator: Perry, Heather A.
Partner: UNT Libraries

The Roles of Genic Behavioral and Biochemical Mechanisms in the Adaption of Minnows of the Genus Notropis (Cyprinidae) to Temperature

Description: Electrophoretic variation at twenty gene loci, patterns of behavioral thermoregulation, and genotype-specific malate dehydrogenase kinetics were investigated among populations of the red shiner, Notropis lutrensis, and the blacktail shiner, N. venustus, collected from thermally altered and thermally unaltered portions of their ranges. Genic variation was found to be high among red shiners and low among blacktail shiners. The behavioral response of the blacktail shiner to temperature was fixed among the populations sampled, whereas the response of the red shiner was mutable. Finally, blacktail shiners have incorporated into their genome an Mdh-B allele which functions well at low temperatures; red shiners, displaying high levels of Mdh-B polymorphism, maintain a more complex set of allozymes which function well over a wide range of environmental temperatures. These data are consistent with reported ecotypic distributions of the species in Texas waters; i.e., blacktail shiners occur in cool, thermally static habitats, and red shiners are tolerant of wide temperature ranges.
Date: December 1981
Creator: Calhoun, Stuart W. (Stuart Wayne)
Partner: UNT Libraries

Report to the William and Flora Hewlett Foundation

Description: A biological model is presented for determining effects of an environmetal variable on a physiological variable. The effect of an environmental variable, temperature, on a physiological variable, oxygen consumption, was studied. (HLW) Measurements were made on oxygen consumption of mice following exposure to different temperatures. A graph is presented to show results. A model was developed to show: thermal regulation; ratio of change in heat production to change in body temperature; thermal capacity of the body; heat transfer coefficient of the fur; and volume of oxygen required to produce a unit of heat by metabolism. The relevance of the results to ecosystems is discussed.
Date: December 1, 1978
Creator: Eisner, E.
Partner: UNT Libraries Government Documents Department

Microwaves affect thermoregulatory behavior in rats

Description: Rats, with their fur clipped, pressed a lever to turn on an infrared lamp while in a cold chamber. When 2450 Megahertz continuous wave microwaves were presented for 15 minutes, the rate of turning on the infrared lamp decreased as a function of the microwave power density, which ranged between 5 MW/cm/sup 2/ and 20 MW/cm/sup 2/. This result indicates that behaviorally significant levels of heating occur at exposure durations and intensities that do not produce reliable changes in either colonic temperature or other behavioral measures. Further study of how microwaves affect thermoregulatory behavior may help us understand phenomena such as reported non-thermal behavioral effects of microwaves.
Date: January 1, 1979
Creator: Stern, S.; Margolin, L.; Weiss, B.; Lu, S.T. & Michaelson, S.M.
Partner: UNT Libraries Government Documents Department

Thermoregulation of fish and turtles in thermally stressed habitats. Annual progress report, October 1, 1977--September 30, 1978

Description: Morphometric and heating and cooling studies on over 100 largemouth bass, Micropterus salmoides, have provided the data needed to refine the time-dependent body temperature model for fish. The model can now track the changes in body temperature of a bass if its weight and water temperature are known. The model is most sensitive to body diameter, body wall thickness, and tissue conductivity. Doubling tissue conductivity is equivalent to decreasing body diameter by a factor or two. Turtles, Chrysemys scripta, living in the heated portion of a cooling reservoir facultatively exploit the warmed water (..delta..T = 4 to 10/sup 0/C) as an auxiliary heat source for behavioral thermoregulation. Turtles in the heated arm of PAR pond have a smaller home range (200 m) than turtles in an ambient portion of the reservoir (507 m). The ability of animals to thermoregulate at a high constant body temperature depends upon the constraints imposed on them by their body size and physical characteristics and those of their environment. The net heat production required to maintain a specific body temperature changes as the size of an ectotherm increases. Operative environmental temperature is an appropriate measure of environmental heat loading and can be used as a predictor of turtle behavior. This concept may become very valuable in quantifying the effect of thermal effluents on turtle and fish behavior.
Date: June 1, 1978
Creator: Spotila, J. R.
Partner: UNT Libraries Government Documents Department

Continuation of studies on thermoregulation of fish and turtles in thermally stressed habitats. Annual progress report, 1 October 1978-30 September 1979

Description: A time dependent mathematical model accurately predicts heart, brain, and gut temperatures of largemouth bass. Body diameter, insulation thickness, and tissue thermal conductivity are controlling variables in the transfer of heat between a fish and water. Fish metabolic rate and water velocity across fish surfaces do not appreciably affect heat transfer rates. Multichannel temperature transmitters telemeter body temperatures of free swimming bass in Pond C on the Savannah River Plant while the behavior of those fish and other bass is recorded by an observer. Field studies of the home ranges and movements of turtles in Par Pond on the Savannah River Plant are completed. We have recorded the movements of 30 individuals fitted with radio transmitters. Distinct differences are apparent in the behavior of turtles in areas affected by heated effluents as compared to those in control areas. Calculations and theoretical analysis of the transient energy exchange of turtles are continuing. Laboratory experiments using /sup 133/Xe indicate that blood flow in the muscles and skin of alligators increases 2 to 6 fold during movement. Relative variation is similar in magnitude to that seen in human muscle. Evaporative water loss from alligators decreases as body size increases. The ratios of respiratory to cutaneous water loss are 1.80 at 5/sup 0/C, 1.18 at 25/sup 0/C and 0.85 at 35/sup 0/C. Boundary layer resistances to evaporative water loss are 6 fold less than predicted by calculations of aerodynamic boundary layers. Body size is a primary factor in determining the thermoregulatory strategy that is to be used by a given animal.Operative environmental temperatures (T/sub e/) are as high as 60/sup 0/C for a turtle basking on a log in the sun. In a rainstorm T/sub e/ drops to 18/sup 0/C. Experiments to measure T/sub e/ for turtles in normal and thermally affected areas are ...
Date: June 1, 1979
Creator: Spotila, J.R.
Partner: UNT Libraries Government Documents Department