Phenology and ecology of hibernation in spotted turtles (Clemmys guttata) near the northern limit of their range

1999 ◽  
Vol 77 (9) ◽  
pp. 1348-1357 ◽  
Author(s):  
Jacqueline D Litzgus ◽  
Jon P Costanzo ◽  
Ronald J Brooks ◽  
Richard E Lee, Jr.

Using mark-recapture techniques, temperature-sensitive radio transmitters, and miniature temperature data loggers we investigated the hibernation ecology of northern temperate zone spotted turtles (Clemmys guttata) in Georgian Bay, Ontario, over 4 winters (1993-1997). We observed 18 hibernacula that were occupied by 34 turtles; 11 hibernacula were apparently occupied by single turtles, and 7 were used communally by up to 9 individuals. Hibernacula were located in swamps and were of 2 types: sphagnum moss hummock (n = 15) and rock cavern (n = 3). Almost half of the individuals (16 of 34) used the same hibernaculum in at least 2 winters. Turtles entered hibernacula between mid-September and October, when their body temperature was between 12 and 16°C, and exited them in mid to late April, when ambient temperatures ranged between 1 and 5°C. A waterproof temperature data logger attached to a turtle indicated that this turtle was protected from freezing in a thermally stable hibernaculum (body temperature range 0.3-3.9°C) despite highly variable (a 37°C change over 5 days) and low air temperatures (minimum -35°C). Loss of body mass (2%) during hibernation was not significant. We observed no mortality within hibernacula over the 4 winters; however, 3 turtles were destroyed by predators near the hibernacula. These data provide insight into the role of climate in limiting the northern distribution of this species.

2001 ◽  
Vol 79 (10) ◽  
pp. 1885-1890 ◽  
Author(s):  
Robert MR Barclay ◽  
Cori L Lausen ◽  
Lydia Hollis

With the development of small implantable data loggers and externally attached temperature-sensitive radio transmitters, increasing attention is being paid to determining the thermoregulatory strategies of free-ranging birds and mammals. One of the constraints of such studies is that without a direct measure of metabolic rate, it is difficult to determine the significance of lowered body temperatures. We surveyed the literature and found that many different definitions have been used to discriminate torpor from normothermy. Many studies use arbitrary temperature thresholds without regard for the normothermic body temperature of the individuals or species involved. This variation makes comparison among studies difficult and means that ecologically and energetically significant small reductions in body temperature may be overlooked. We suggest that normothermic body temperature for each individual animal should be determined and that torpor be defined as occurring when the body temperature drops below that level. When individuals' active temperatures are not available, a species-specific value should be used. Of greater value, however, are the depth and duration of torpor bouts. We suggest several advantages of this definition over those used in the past.


1996 ◽  
Vol 74 (9) ◽  
pp. 1778-1781 ◽  
Author(s):  
Doris Audet ◽  
Donald W. Thomas

The facultative depression of body temperature represents an important energy strategy for small homeotherms. However, measuring body temperature under field conditions by means other than externally attached temperature-sensitive radio transmitters is problematical. We show that skin temperatures measured by external radio transmitters can accurately reflect core temperature for the bat Carollia perspicillata. We compared body and skin temperatures at three ambient temperatures (Ta; 21, 26, and 31 °C). The difference between skin and body temperature (ΔT) was linearly correlated with Ta and can be predicted by ΔT = 4.396 − 0.118Ta. We argue that external temperature-sensitive radio transmitters can provide a reliable index of core temperature and so permit the study of torpor or facultative hypothermia under field conditions.


2011 ◽  
Vol 32 (1) ◽  
pp. 83-92 ◽  
Author(s):  
Gabriel Picard ◽  
Gabriel Blouin-Demers ◽  
Marie-Andrée Carrière

AbstractIn ectotherms, variation in body temperature (Tb) affects physiological performance and, ultimately, fitness. Therefore, reptiles regulate Tb behaviourally by choosing habitats of optimal temperature. The main goal of this study was to determine the link between patterns of thermoregulation and habitat selection in Common Musk Turtles inhabiting a thermally challenging region. We expected habitat selection to be based on the fulfillment of thermoregulatory requirements, which can be accomplished by selecting thermally superior habitats. From early May to late August 2007, we tracked 22 Common Musk Turtles with temperature-sensitive radio-transmitters and collected daily Tb profiles with automated radio-telemetry data loggers. In addition, temperature data loggers were placed in the study area to measure the range of environmental operative temperatures (Te) available to musk turtles. The habitats with the highest thermal quality were aquatic habitats with surface cover (i.e., lily pads, macrophytes, etc.) followed by shallow water. As expected, musk turtles used habitats non-randomly and had a strong preference for thermally superior habitats. This is consistent with the typical aquatic basking behaviour observed in musk turtles, suggesting that there is a strong link between thermal quality of habitats and habitat selection, even in this almost entirely aquatic turtle.


Animals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1388
Author(s):  
Ted Friend ◽  
Giulia Corsini ◽  
Vincent Manero ◽  
Raffaella Cocco

The documentation of diurnal patterns in body temperature in lions could be important because disruption of circadian patterns can be a useful measure of distress. This study quantified changes in body temperature of seven African lions (Panthera leo) at 5 min intervals during cold conditions from noon until the ingested body temperature loggers were expelled the next day. Thirteen loggers were fed to 11 lions during their daily noon feeding, while ambient temperatures were also recorded using six data loggers. The lions had continuous access to their dens and exercise pens during the day but were restricted to their heavily bedded dens that also contained a heat lamp from 23:00 until 08:00 the next day. Body temperatures averaged 37.95 ± 0.42 °C at 15:50, and 36.81 ± 0.17 °C at 06:50 the next day, 30 min before the first loggers passed from a lion, and were significantly different (t-test, t = 8.09, df = 6, p < 0.0003). The mean duration for the time of passage was 22 ± 2.69 (h ± SD), so future studies using the noninvasive feeding of temperature loggers need to consider that time frame.


Ardea ◽  
2009 ◽  
Vol 97 (1) ◽  
pp. 120-124 ◽  
Author(s):  
Joseph B. Williams ◽  
B.I. Tieleman ◽  
Mohammed Shobrak

2017 ◽  
Vol 54 (1) ◽  
pp. 6-14
Author(s):  
Mitchell D. Richmond ◽  
Robert C. Pearce ◽  
Ben M. Goff ◽  
William A. Bailey

Significant variability in cured-leaf tobacco-specific nitrosamine (TSNA) content is commonly observed when sampling within dark air-curing barns. This variability may be due to inconsistency in the curing environment within different areas of the barn. A study was initiated in 2012, through support from a CORESTA Study Grant, to evaluate if cured-leaf TSNA content is related to microenvironmental conditions in the barn. Low-converter (TRsc) and high-converter (TRHC) selections of TR Madole dark tobacco were air cured in barns near Princeton and Lexington, KY. Temperature and relative humidity were measured with data loggers placed at 27 different locations within each barn for the duration of curing. There were no significant effects of individual data logger placement in either variety selection on hours above 24°C temperature, hours above 80% relative humidity, or TSNA; therefore, we investigated these data within the 3-dimensional aspects of tier, room, and bent within each barn. There were various effects of tier, room, and bent on temperature, relative humidity, and TSNA. Temperature data followed an understandable pattern across tiers in the barn within each year and location; however, relative humidity and TSNA were more difficult to characterize adequately. There was a significant relationship between hours above 24°C and TSNA, but not hours above 80% relative humidity. This study has shown that the effect of within-barn position on TSNA cannot be easily predicted.


2021 ◽  
Vol 376 (1830) ◽  
pp. 20200213 ◽  
Author(s):  
Nils Linek ◽  
Tamara Volkmer ◽  
J. Ryan Shipley ◽  
Cornelia W. Twining ◽  
Daniel Zúñiga ◽  
...  

In a seasonal world, organisms are continuously adjusting physiological processes relative to local environmental conditions. Owing to their limited heat and fat storage capacities, small animals, such as songbirds, must rapidly modulate their metabolism in response to weather extremes and changing seasons to ensure survival. As a consequence of previous technical limitations, most of our existing knowledge about how animals respond to changing environmental conditions comes from laboratory studies or field studies over short temporal scales. Here, we expanded beyond previous studies by outfitting 71 free-ranging Eurasian blackbirds ( Turdus merula ) with novel heart rate and body temperature loggers coupled with radio transmitters, and followed individuals in the wild from autumn to spring. Across seasons, blackbirds thermoconformed at night, i.e. their body temperature decreased with decreasing ambient temperature, but not so during daytime. By contrast, during all seasons blackbirds increased their heart rate when ambient temperatures became colder. However, the temperature setpoint at which heart rate was increased differed between seasons and between day and night. In our study, blackbirds showed an overall seasonal reduction in mean heart rate of 108 beats min −1 (21%) as well as a 1.2°C decrease in nighttime body temperature. Episodes of hypometabolism during cold periods likely allow the birds to save energy and, thus, help offset the increased energetic costs during the winter when also confronted with lower resource availability. Our data highlight that, similar to larger non-hibernating mammals and birds, small passerine birds such as Eurasian blackbirds not only adjust their heart rate and body temperature on daily timescales, but also exhibit pronounced seasonal changes in both that are modulated by local environmental conditions such as temperature. This article is part of the theme issue ‘Measuring physiology in free-living animals (Part I)’.


Finisterra ◽  
2012 ◽  
Vol 36 (71) ◽  
Author(s):  
Carla Mora ◽  
Gonçalo Teles Vieira ◽  
Maria João Alcoforado

The Serra da Estrela is part of the Iberian Central Cordillera and isthe highest mountain in Portugal (1,993 m ASL). The Torre-Penhas Douradas and Alto da Pedrice-Malhada Alta plateaus with altitudes between 1,400 and 1,993m, which are separated by the Alforfa and Zêzere valleys dominate the highest part of the range. The central massif is dissected by several glacially sculpted valleys thatoriginate reliefs from 200 to 700m. This morphological diversity controls to a great extent the local climates of the mountain. Nine air temperature data loggers were installed in contrasting topographic situations, with special emphasis to valley floors and interfluve sites. Data collection was made each 2-hours from 27th December 1999 to 27th March 2000. Minima temperature most of the times occurs at 7 UTC. The minimum air temperature patterns based on the data from the nine sites were classified using k-means. Two contrasting events were chosen for the centroids of the classification. Cluster 1 represents the stable events with thermal inversions in the valleys and higher temperature in the interfluves. The valley floors at higher altitudes present lower temperatures than the ones at lower positions. Cluster 2 groups the unstable episodes with more turbulence and a temperature decrease controlled by altitude. In this group temperature does not depends on thetopographic position.


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