Effects of gap-based silviculture on thermal biology of a terrestrial reptile

2018 ◽  
Vol 45 (1) ◽  
pp. 72 ◽  
Author(s):  
Mickey Agha ◽  
Brian D. Todd ◽  
Ben Augustine ◽  
John M. Lhotka ◽  
Leo J. Fleckenstein ◽  
...  
Keyword(s):  
Body Temperature ◽  
Time Of Day ◽  
Canopy Gaps ◽  
Body Temperatures ◽  
Thermal Environments ◽  
Silvicultural Practices ◽  
Box Turtles ◽  
Box Turtle ◽  
Eastern Box Turtles ◽  
Environmental Temperatures

Context Terrestrial reptiles require varied thermal environments to promote optimal physiological performance, growth, reproduction, and survival. Aims Our study was designed to determine whether gap-based silvicultural practices offer suitable thermal environments for eastern box turtles (Terrapene carolina) by examining environmental temperature variation and body temperature of eastern box turtles in, and adjacent to, canopy gaps. Methods We recorded box turtle body temperature from 20 radio-tracked turtles and environmental temperatures (canopy gaps and undisturbed habitat) using temperature loggers from June to September 2014 in a managed forest after canopy gaps (0.28–1.13 ha gap–1) were created via gap-based silviculture. Key results Over the four-month study period, gap temperatures were generally higher than adjacent undisturbed microhabitats. Box turtle body temperatures were closely correlated with environmental temperatures in undisturbed habitat in June and July. Turtle body temperatures were, however, closely correlated with environmental temperatures in canopy gaps in August and September. In addition, box turtles in our study had activity areas that overlapped canopy gaps from 0 to 65%, depending on the individual. As percentage overlap of canopy gaps increased, turtle body temperatures were increasingly correlated with canopy gap temperatures. Furthermore, as percentage overlap of canopy gaps increased, daily mean body temperature records consistently stayed within the preferred box turtle body temperature range (20.2–26.2°C). Conclusions Our study suggests that gap-based silviculture can create thermally compatible environments for box turtles depending on the time of day and year, and that box turtles use these microhabitats to thermoregulate. Implications The application of relatively small-scale silvicultural practices (≤1 ha gap–1) that provide heterogeneity in forest structure, composition, and function may be a useful alternative to clearcutting and other intensive harvesting methods that are associated with declines in terrestrial reptile populations.

Shivering and nonshivering thermogenesis in the bat (Myotis myotis Borkh.) during arousal from hibernation

1970 ◽  
Vol 48 (2) ◽  
pp. 102-106 ◽  
Author(s):  
Jiří Mejsnar ◽  
Ladislav Janský
Keyword(s):  
Body Temperature ◽  
Great Increase ◽  
Late Period ◽  
Nonshivering Thermogenesis ◽  
Body Temperatures ◽  
Metabolic Capacity ◽  
Middle Range ◽  
Myotis Myotis ◽  
Speed Up ◽  
Environmental Temperatures

Nonshivering thermogenesis exists in the bat (Myotis myotis Borkh.) arousing from hibernation at environmental temperatures of 4–6 °C. Nonshivering thermogenesis is essential for the start of the arousal, and it is stimulated by noradrenaline since hexamethonium prevents the increase in metabolism and body temperature. Injection of noradrenaline abolishes this inhibition by hexamethonium by inducing nonshivering thermogenesis. After simultaneous administration of hexamethonium and alderlin no calorigenic effect of noradrenaline occurs. Shivering heat production during arousal appears at body temperatures between 10 and 17 °C predominantly. In normothermic bats the calorigenic effect of noradrenaline was observed, which indicates that nonshivering thermogenesis might also be present in awake animals. During arousal at 25 °C a great increase in intensity of shivering was observed. Elimination of nonshivering thermogenesis by hexamethonium does not prevent the attainment of the homoiothermic level of body temperature, and administration of noradrenaline does not speed up the process of arousal. As is evident from the metabolic capacity of the brown fat, the heat derived from this organ could maximally participate in total metabolism by 25% at the beginning and at the late period of arousal. In the middle range of body temperatures its significance for total metabolism is only about 10–13%.

scholarly journals Behavioral adaptations in Ameivula ocellifera (Squamata: Teiidae) in response to thermal environmental changes

2019 ◽  
Vol 18 (2) ◽  
pp. 225-240
Author(s):  
Raul Fernandes Dantas Sales ◽  
Eliza Maria Xavier Freire
Keyword(s):  
Body Temperature ◽  
Rainy Season ◽  
Environmental Changes ◽  
Northeastern Brazil ◽  
Body Temperatures ◽  
Thermal Environments ◽  
Behavioral Adaptations ◽  
Air Temperatures ◽  
External Sources ◽  
Regulate Body Temperature

Behavioral adaptations in Ameivula ocellifera (Squamata: Teiidae) in response to thermal environmental changes. Lizards rely on external sources to regulate body temperature, but in many species, it is not known whether lizards are able to change their thermoregulatory behaviors in response to variations in thermal environments. The seasonal thermal ecology of three populations of the Brazilian whiptail lizard, Ameivula ocellifera, in northeastern Brazil (two Caatinga sites and one in the Atlantic Forest) was investigated. The relationships between body temperature and microhabitat temperatures (substrate and air), and between body temperature and thermoregulatory behavior (i.e., time of exposure to sunlight classes and time spent basking) were explored. The average body temperatures of the lizards were 38–39°C; these neither varied seasonally nor among populations. Substrate and air temperatures are lower at the natural Caatinga site, and lizards in there spent less time in the shade and more time exposed to the sun. Microhabitat temperatures vary seasonally in natural Caatinga; they are lower in the rainy season, when lizards spent more time exposed to sun and less time in fltered sun. Lizard body temperatures exceeded microhabitat temperatures in the rainy season in all three populations; however, they did not exceed substrate temperature in the dry season. In each of the populations, lizards with low body temperatures during cloudy conditions spent more time basking. Thus, A. ocellifera adjusts its body temperature behaviorally to compensate for seasonal changes in environmental temperatures, as well as geographic thermal variation throughout its range.

Temperature Diurne d'Activité des Males et des Femelles de Lacerta vivipara

1987 ◽  
Vol 8 (4) ◽  
pp. 393-400 ◽  
Author(s):  
Benoit Heulin
Keyword(s):  
Body Temperature ◽  
Regression Line ◽  
Body Temperatures ◽  
Mean Body Temperature ◽  
Pregnant Females ◽  
The Mean ◽  
Lacerta Vivipara ◽  
Environmental Temperatures

AbstractMean body temperature (TC) of Lacerta vivpara ranges from 26°8 to 32° at Paimpont (France). There is a highly significant correlation between environmental temperatures (TS) and body temperatures (TC). The mean body temperature of pregnant females is lower than that of males and non-pregnant females. Also, the regression line TC = f(TS) calculated for pregnant females is different from those calculated for males and non-pregnant females. The possible relations between pregnancy and body temperature are discussed.

Correlations between body temperature and environmental factors and their variations with activity in garter snakes (Thamnophis)

1984 ◽  
Vol 62 (11) ◽  
pp. 2244-2249 ◽  
Author(s):  
Patrick T. Gregory
Keyword(s):  
Body Temperature ◽  
Environmental Variables ◽  
Cloud Cover ◽  
Garter Snakes ◽  
Body Temperatures ◽  
Data Set ◽  
Explained Variation ◽  
Highly Correlated ◽  
Activity Groups ◽  
Environmental Temperatures

The aim of this study was to determine the extent to which several environmental variables were associated with body temperatures of three species of garter snakes (Thamnophis) on Vancouver Island, and whether or not these associations changed with different activities of snakes. Perhaps because the data set was quite heterogeneous, no differences were observed between body temperatures of different species or sexes. In all activity groups, environmental temperatures were the variables most highly correlated with body temperatures; factors such as visible light intensity and cloud cover also were correlated with body temperature in some cases, but added little to the "explained" variation of body temperature. There was little evidence of seasonal or diel fluctuation in body temperature, but more careful data collection may be required to detect these. The correlation between body and environmental temperatures was highest for snakes under cover and lowest for moving snakes. Basking snakes in general were intermediate between these two groups, but snakes basking in the sun under sunny skies showed low correlation between body and environmental temperatures. Snakes, therefore, had body temperatures relatively independent of environmental temperatures under certain circumstances, but conclusions about thermoregulation could not be drawn from these data.

scholarly journals Consumption Patterns of a Generalist Omnivore: Eastern Box Turtle Diets in the Long Island Pine Barrens

Diversity ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 345
Author(s):  
Miranda P. Figueras ◽  
Timothy M. Green ◽  
Russell L. Burke
Keyword(s):  
Optimal Foraging ◽  
Prey Species ◽  
Consumption Patterns ◽  
Pine Barrens ◽  
Terrapene Carolina ◽  
Eastern Box Turtle ◽  
Box Turtles ◽  
Box Turtle ◽  
Low Levels ◽  
Eastern Box Turtles

Eastern Box Turtles (Terrapene carolina) are diet generalists and as such are predicted to have diverse diets in which familiar, low-quality foods are eaten consistently at low levels, and high-quality foods are rare but eaten whenever available. Previous work showed that they feed opportunistically on seasonally available plants (shoots, leaves, flowers, and fruit), invertebrates, mushrooms, and occasionally carrion. We used fecal samples to test optimal foraging predictions relevant to diet generalists and also whether the Eastern Box Turtle diets varied seasonally in a northeastern U.S. pine-oak habitat. We found that in-depth prey species consumption patterns of six different individuals were similar to those of the sampled population overall. Leaf and stem material was consumed by 100% of the turtles in all months despite being lower-quality than other prey available. Invertebrates were consumed by at least 80% of turtles in every study period; Coleopterans were found more commonly than other invertebrates. Snails were not eaten by more than 20% of the turtles in any study period, and mushroom consumption varied from 31–75% of samples in different study periods. Monthly diet overlap was measured using both Pianka’s Index of Overlap (PIO) and the Morisita–Horn Index (MH). The PIO method indicated that the prey consumption patterns were broadly similar from June–October, while the M–H method showed that only the July vs. August comparison was highly similar. The turtle diets changed only slightly between seasons, and they conform to predictions of diet generalist models usually applied to mammals.

EXERCISE AND TEMPERATURE REGULATION IN LEMMINGS AND RABBITS

1955 ◽  
Vol 33 (1) ◽  
pp. 428-435 ◽  
Author(s):  
J. S. Hart ◽  
O. Heroux
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Heat Production ◽  
Temperature Regulation ◽  
Thermal Equilibrium ◽  
Environmental Temperature ◽  
Body Temperatures ◽  
Temperature Changes ◽  
Extreme Cold ◽  
Environmental Temperatures

Oxygen consumption and body temperatures were determined in lemmings at environmental temperatures from 20 °C. to −10 °C. and in rabbits from 20 °C. to −50 °C. Body insulation indices were estimated as the ratio [Formula: see text]. In both species, increase in activity and decrease in temperature led to increases in oxygen consumption that were additive over the temperature range. Oxygen increments of work were independent of environmental temperature in the absence of progressive hypothermia. Work led to increases in body temperature at the upper environmental temperatures and to decreases in body temperature at the lower temperatures. In extreme cold, rabbits became progressively hypothermic during work and there was a decline in oxygen consumption. Body temperatures started to fall at environmental temperatures 18 °C. higher in working than in resting rabbits. Insulation was lower in working than in resting animals. During exercise there appears to be a readjustment of body temperature, insulation, and heat loss until thermal equilibrium is established. The regulation of heat production, within limits, seems to be independent of body-temperature changes during exercise.

Thermal environments of overwintering Eastern Box Turtles (Terrapene carolina carolina)

2010 ◽  
Vol 88 (11) ◽  
pp. 1086-1094 ◽  
Author(s):  
Yulia Savva ◽  
Christopher W. Swarth ◽  
Jayant Gupchup ◽  
Katalin Szlavecz
Keyword(s):  
Air Temperature ◽  
Site Fidelity ◽  
Mixed Effects ◽  
Thermal Environments ◽  
Terrapene Carolina ◽  
Box Turtles ◽  
Eastern Box Turtles ◽  
Terrapene Carolina Carolina ◽  
Overwintering Site ◽  
General Climate

Using a mixed-effects model for 21 Eastern Box Turtles ( Terrapene carolina carolina (L., 1758)) over three winters in Maryland, USA, we demonstrate that overwintering-site temperature was mainly related to air temperature. After controlling for air temperature, between-year variation accounted for 7%, between-turtle variation accounted for 3%, and variation owing to age class accounted for 1% of the total variation in overwintering-site temperature. Turtles showed overwintering-site fidelity and the location of overwintering sites did not depend on sex or age. According to the developed function, air temperature would have to increase by 3 °C over the overwintering period to raise the temperature of overwintering sites by about 1 °C, assuming no changes in other environmental factors; this level of warming is not expected until 2070–2090 according to general climate circulation models.

Thermoregulation of the lizard Barisia imbricata at altitudinal extremes

2019 ◽  
Vol 40 (3) ◽  
pp. 349-360
Author(s):  
Natalia Fierro-Estrada ◽  
Yasmin Guadalupe González González ◽  
Donald B. Miles ◽  
Margarita Martínez Gómez ◽  
Andrés García ◽  
...  
Keyword(s):  
Body Temperature ◽  
Narrow Range ◽  
Thermal Ecology ◽  
Body Temperatures ◽  
Mean Body Temperature ◽  
Thermal Requirements ◽  
Air Temperatures ◽  
Preferred Temperatures ◽  
Environmental Temperatures ◽  
Two Populations

Abstract Ambient temperature is a primary factor affecting the physiology and activity of reptiles. Thermoregulation involves a series of mechanisms to maintain an organism’s body temperature within a narrow range. The study of thermal ecology of lizards is relevant for understanding their distribution, life history, ecology and thermal requirements. Moreover, determining how species are able to attain physiologically active body temperatures in challenging environments is necessary for assessing the risk of extinction due to climate change, especially for threatened endemic species. We evaluated and compared the thermal ecology of two populations of the viviparous lizard Barisia imbricata, at contrasting elevations (2200 and 3700 m). We obtained variation in thermal data from winter through autumn for multiple years. We determined thermal efficiency indices based on field active body temperatures, preferred temperatures (in a thermal gradient), and operative environmental temperatures (according to null models). We also recorded substrate and air temperatures at the time of capture. Mean body temperature of both populations showed a positive correlation with environmental temperatures. We found significant seasonal differences in body temperature in both populations, and between body temperatures of the two populations. Our results suggest that B. imbricata is an eurythermic species and can thermoregulate actively at any given time. However, when environmental temperatures are within the range of preferred temperatures, the species does not engage in thermoregulatory behavior. This information expands knowledge on the range of possible thermal responses to environmental variation within a species.

EXERCISE AND TEMPERATURE REGULATION IN LEMMINGS AND RABBITS

1955 ◽  
Vol 33 (3) ◽  
pp. 428-435 ◽  
Author(s):  
J. S. Hart ◽  
O. Heroux
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Heat Production ◽  
Temperature Regulation ◽  
Thermal Equilibrium ◽  
Environmental Temperature ◽  
Body Temperatures ◽  
Temperature Changes ◽  
Extreme Cold ◽  
Environmental Temperatures

Oxygen consumption and body temperatures were determined in lemmings at environmental temperatures from 20 °C. to −10 °C. and in rabbits from 20 °C. to −50 °C. Body insulation indices were estimated as the ratio [Formula: see text]. In both species, increase in activity and decrease in temperature led to increases in oxygen consumption that were additive over the temperature range. Oxygen increments of work were independent of environmental temperature in the absence of progressive hypothermia. Work led to increases in body temperature at the upper environmental temperatures and to decreases in body temperature at the lower temperatures. In extreme cold, rabbits became progressively hypothermic during work and there was a decline in oxygen consumption. Body temperatures started to fall at environmental temperatures 18 °C. higher in working than in resting rabbits. Insulation was lower in working than in resting animals. During exercise there appears to be a readjustment of body temperature, insulation, and heat loss until thermal equilibrium is established. The regulation of heat production, within limits, seems to be independent of body-temperature changes during exercise.

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