Accelerometer informed time-energy budgets reveal the importance of temperature to the activity of a wild, arid zone canid

Abstract Background Globally, arid regions are expanding and becoming hotter and drier with climate change. For medium and large bodied endotherms in the arid zone, the necessity to dissipate heat drives a range of adaptations, from behaviour to anatomy and physiology. Understanding how apex predators negotiate these landscapes and how they balance their energy is important as it may have broad impacts on ecosystem function. Methods We used tri-axial accelerometry (ACC) and GPS data collected from free-ranging dingoes in central Australia to investigate their activity-specific energetics, and activity patterns through time and space. We classified dingo activity into stationary, walking, and running behaviours, and estimated daily energy expenditure via activity-specific time-energy budgets developed using energy expenditure data derived from the literature. We tested whether dingoes behaviourally thermoregulate by modelling ODBA as a function of ambient temperature during the day and night. We used traditional distance measurements (GPS) as well as fine-scale activity (ODBA) data to assess their daily movement patterns. Results We retrieved ACC and GPS data from seven dingoes. Their mass-specific daily energy expenditure was significantly lower in summer (288 kJ kg− 1 day− 1) than winter (495 kJ kg− 1 day− 1; p = 0.03). Overall, dingoes were much less active during summer where 91% of their day was spent stationary in contrast to just 46% during winter. There was a sharp decrease in ODBA with increasing ambient temperature during the day (R2 = 0.59), whereas ODBA increased with increasing Ta at night (R2 = 0.39). Distance and ODBA were positively correlated (R = 0.65) and produced similar crepuscular patterns of activity. Conclusion Our results indicate that ambient temperature may drive the behaviour of dingoes. Seasonal differences of daily energy expenditure in free-ranging eutherian mammals have been found in several species, though this was the first time it has been observed in a wild canid. We conclude that the negative relationship between dingo activity (ODBA) and ambient temperature during the day implies that high heat gain from solar radiation may be a factor limiting diurnal dingo activity in an arid environment.

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Accelerometer informed time-energy budgets reveal the importance of temperature to the activity of a wild, arid zone canid

10.21203/rs.3.rs-128608/v1 ◽

2020 ◽

Author(s):

Jack Tatler ◽

Shannon E. Currie ◽

Phillip Cassey ◽

Anne K. Scharf ◽

David A. Roshier ◽

...

Keyword(s):

Solar Radiation ◽

Energy Expenditure ◽

Ambient Temperature ◽

Negative Relationship ◽

Energy Budgets ◽

Gps Data ◽

Daily Energy Expenditure ◽

Body Acceleration ◽

Daily Energy ◽

Free Ranging

Abstract BackgroundMovement is the major contributor to active energy expenditure in most vertebrates and it is regularly characterised by body acceleration that can be captured by animal-attached accelerometers (ACC). Overall dynamic body acceleration (ODBA) is a metric derived from ACC data, which can be used as a proxy for energy expenditure over fine time scales. MethodsHere, we used ACC and GPS data collected from free-ranging dingoes in central Australia to investigate their activity-specific energetics, and activity patterns through time and space. We classified dingo activity into stationary, walking, and running behaviours, and estimated daily energy expenditure via activity-specific time-energy budgets. We tested whether dingoes behaviourally thermoregulate by modelling ODBA as a function of ambient temperature (Ta) during the day and night. We used traditional distance measurements (GPS) as well as fine-scale activity (ODBA) data to assess their daily movement patterns.ResultsWe retrieved ACC and GPS data from seven dingoes. Their mass-specific daily energy expenditure was significantly lower in summer (288 kJ kg-1 day-1) than winter (495 kJ kg-1 day-1; p = 0.03). Overall, dingoes were much less active during summer where 91% of their day was spent stationary in contrast to just 46% during winter. There was a sharp decrease in ODBA with increasing ambient temperature during the day (R2 = 0.59), whereas ODBA increased with increasing Ta at night (R2 = 0.39). Distance and ODBA were positively correlated (R = 0.65) and produced similar crepuscular patterns of activity.ConclusionOur results indicated solar radiation and ambient temperature drove the behaviour of dingoes. Seasonal differences of daily energy expenditure (DEE) in free-ranging eutherian mammals have been found in several species, though this was the first time it has been observed in a wild canid. The negative relationship between dingo activity (ODBA) and Ta during the day implies that high heat gain from solar radiation is a factor limiting diurnal dingo activity in an arid environment.

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Winter energy expenditure and the distribution of southern flying squirrels

Canadian Journal of Zoology ◽

10.1139/z91-359 ◽

1991 ◽

Vol 69 (10) ◽

pp. 2548-2555 ◽

Cited By ~ 54

Author(s):

Paul Stapp ◽

Peter J. Pekins ◽

William W. Mautz

Keyword(s):

Energy Expenditure ◽

Heat Loss ◽

Current Distribution ◽

Basal Metabolism ◽

Energy Budgets ◽

Late Winter ◽

Daily Energy Expenditure ◽

Flying Squirrels ◽

Tree Cavities ◽

Daily Energy

The southern flying squirrel (Glaucomys volans) forms large aggregations inside nest-lined tree cavities to reduce exposure to winter temperatures. We measured oxygen consumption of individuals and grouped flying squirrels in Plexiglas and nest-box chambers in New Hampshire to determine savings provided by huddling and nest construction. Because G. volans breeds during late winter, we also measured energy expenditure of females during gestation and lactation. These data were used to construct daily energy budgets for flying squirrels during winter and to investigate the relationship between this species' cold tolerance and its current distribution. Flying squirrels had lower basal metabolism (0.95 cm3 O2∙g−1∙h−1) and rate of heat loss (0.11 cm3 O2∙g−1∙h−1∙ °C−1) than predicted according to mass. Peak reproductive costs (1 week postparturition) were 170% of nonbreeding requirements. At 9 °C, huddling in groups of three and six reduced energy expenditure by 27 and 36%, respectively. Compared with individuals without nests, nest insulation decreased heat loss by 37% for single squirrels and reduced lower critical temperature from 26.5 to 12.2 °C for groups of six. As estimated from our budget, aggregating reduces winter daily energy expenditure by 26–33%. At the northern range boundary, daily expenditure for squirrels using both aggregations and nests (2.5 times basal metabolism) and for females during peak lactation (3.9 times basal metabolism) was similar to estimates of maximal daily energy expenditure in the literature. We speculate that additional thermoregulatory costs and the decreased abundance of hard mast for winter caches prevent G. volans from occupying areas north of its current distribution.

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Daily Energy Expenditure in Free-ranging Gopher Tortoises (Gopherus Polyphemus)

Copeia ◽

10.1643/0045-8511(2006)006[0129:deeifg]2.0.co;2 ◽

2006 ◽

Vol 2006 (1) ◽

pp. 129-136 ◽

Cited By ~ 5

Author(s):

Patrick G. R. Jodice ◽

Deborah M. Epperson ◽

G. HenkVisser

Keyword(s):

Energy Expenditure ◽

Daily Energy Expenditure ◽

Gopherus Polyphemus ◽

Daily Energy ◽

Free Ranging

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Differential sex-related winter energetics in free-ranging snowshoe hares (Lepus americanus)

Canadian Journal of Zoology ◽

10.1139/cjz-2015-0074 ◽

2016 ◽

Vol 94 (2) ◽

pp. 115-121 ◽

Cited By ~ 3

Author(s):

E. Ellsworth ◽

M.R. Boudreau ◽

K. Nagy ◽

J.L. Rachlow ◽

D.L. Murray

Keyword(s):

Energy Expenditure ◽

Food Availability ◽

Lepus Americanus ◽

Energetic Cost ◽

Food Supplementation ◽

Natural Food ◽

Daily Energy Expenditure ◽

Snowshoe Hares ◽

Daily Energy ◽

Free Ranging

Animals spend considerable time and energy acquiring food to meet their metabolic requirements, but if energetic or fitness costs are substantive, such as during winter, then some individuals may limit daily energy expenditure by reducing foraging duration. To date, the prevalence and magnitude of such compensatory foraging responses are poorly known. We examined energy balance compensation in free-ranging snowshoe hares (Lepus americanus Erxleben, 1777) via a food supplementation experiment to determine whether individuals reduced their daily energy expenditure (DEE) and activity periods in response to increased food availability. Overall, food supplementation had no effect on diel activity patterns, although males had higher DEE compared with females. During early and mid-winter, hares did not alter their activity periods in response to food supplementation, but during late winter, when natural food availability declined, food-supplemented females (but not males) were ∼11% less active compared with controls. Natural food likely was sufficient and could have been acquired at relatively low energetic cost, but because males likely have higher DEE due to mating behavior whereas females may limit their activity (and thus DEE) to reduce predation risk, we conclude that gender-specific life-history demands can over-ride predicted responses to supplemental food when baseline food abundance is adequate.

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