Journal of thermal biology最新文献

{"title":"Evaluating the physiological benefits of behavioral flexibility in chacma baboons (Papio ursinus) using a biophysical model","authors":"Christine D. Grebe ,&nbsp;Paul D. Mathewson ,&nbsp;Warren P. Porter ,&nbsp;Richard McFarland","doi":"10.1016/j.jtherbio.2024.104042","DOIUrl":"10.1016/j.jtherbio.2024.104042","url":null,"abstract":"<div><div>As opportunistic generalists occupying a range of ecological niches, chacma baboons (<em>Papio ursinus</em>) are considered a highly flexible species of relatively low conservation priority. Underlying their ecological flexibility is a repertoire of behavioral strategies observed in response to ecological stressors. Although these strategies are relatively well-documented, we know very little about how they impact upon an individual’s thermal and energetic physiology, which can influence population-level reproductive potential in the face of climatic warming. Here, we used Niche Mapper™ to construct a biophysical model that integrates morphometric, autonomic, and behavioral inputs to predict the core body temperature of chacma baboons in response to varied microclimate conditions. The predictive integrity of the model was confirmed by comparing model outputs with the core body temperature of a free-living chacma baboon equipped with an intra-abdominal temperature-sensitive data logger. When behavioral thermoregulation was incorporated, our model predicted body temperature within 1.5 °C of the observed temperature for 94% of hours. Of the tested behavioral thermoregulatory responses, shade-seeking provided the greatest thermal benefit, reducing predicted core body temperature by an average of 0.9 °C during daytime hours. Evaporative heat-dissipation strategies (sweating or swimming) were also highly effective in circumventing hyperthermia in our modeled individual, with an average body temperature reduction of 0.6 °C. Our findings underscore the critical importance of behavioral thermoregulatory strategies coupled with access to essential microhabitat features, water and shade, to achieve homeothermy in a warming climate.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"127 ","pages":"Article 104042"},"PeriodicalIF":2.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142971582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of warm carbon dioxide insufflation vs. local heat on shoulder pain in laparoscopic cholecystectomy: A randomized clinical trial","authors":"Saeideh Vaziri Kordestani ,&nbsp;Ebrahim Nasiri-Formi ,&nbsp;Mohammad Davood Qane ,&nbsp;Elmira Khodabakhsh","doi":"10.1016/j.jtherbio.2024.104041","DOIUrl":"10.1016/j.jtherbio.2024.104041","url":null,"abstract":"<div><h3>Objective</h3><div>Laparoscopic cholecystectomy is a common procedure for gallbladder diseases, but many patients experience shoulder pain due to pneumoperitoneum. This study investigates the comparative effectiveness of warm carbon dioxide gas insufflation versus local heat application in reducing shoulder pain after laparoscopic cholecystectomy. We also examined changes in body temperature during surgery and postoperative shivering in the intervention and control groups.</div></div><div><h3>Methods</h3><div>93 patients undergoing elective laparoscopic cholecystectomy were divided into three groups: Group A: Warm carbon dioxide gas, Group B: Local heat, Group C: Control. Patients' body temperature, shivering, and right/left shoulder pain were evaluated. Data was analyzed using SPSS software with a significance level of 0.05 and GEE regression.</div></div><div><h3>Results</h3><div>Mean right shoulder pain scores at 48 h and mean left shoulder pain scores at 24/48 h post-operation were significantly lower in the intervention groups compared to control (p &lt; 0.05). There were differences in temperature body during surgery among the study groups. The mean body temperature was 0.48 units higher in Group B compared to the control group. Group A had a 0.14-unit lower temperature than the control group, although this difference was not statistically significant. No significant difference in postoperative shivering was observed among the groups.</div></div><div><h3>Conclusion</h3><div>Based on the findings of this study, Methods of warm carbon dioxide gas insufflation and local heating in laparoscopic cholecystectomy reduce shoulder pain in patients during the postoperative phase. The local heating method significantly increased the patients' body temperature compared to the other two groups, and shivering was similar across all three groups.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"127 ","pages":"Article 104041"},"PeriodicalIF":2.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"“Sadness smile” curve: Processing emotional information from social network for evaluating thermal comfort perception","authors":"Yifeng Liu ,&nbsp;Xinyue Zhang ,&nbsp;Hongxu Wei ,&nbsp;Zhanhua Cao ,&nbsp;Peng Guo","doi":"10.1016/j.jtherbio.2024.104025","DOIUrl":"10.1016/j.jtherbio.2024.104025","url":null,"abstract":"<div><div>Thermal comfort is a subjective perception, hence conventional evaluation using meteorological factors faces a technical challenge in precise assessment. Human beings have the nature to differentiate expressions of facial emotions when varied thermal environments are perceived. Facial expression scores can be taken as a predictor of perceived thermal comfort which can be precisely assessed using deep learning against physical factors. In this study, a total of 8314 facial photos were obtained from volunteers in 82 parks of 49 cities via social network. Facial expressions were analyzed to happy, sad, and neutral emotion scores using a professional instrument. Temperature-responsive changes in sadness score (SS) can be fit by a U-shaped curve which was called as the ‘sadness smile’. The stationary point of second-order derivative was identified to predict the-most-comfort temperature (22.84 °C), across which a tangent line framed the range of comfort temperatures based on two intersections with first-order derivatives (14.62–31.06 °C). Critical temperature points were identified along a positively correlated line of modified temperature-humidity index against increasing temperatures, which were negatively correlated with SS in autumn and winter. The ResNet model was demonstrated to excellently predict emotion-based thermal comfort perceptions in validation set (<em>R</em>² &gt; 0.5). A nation-wide mapping suggested that many cities of Northwest and North China had local environments that can be perceived with comfort assessed by SS against thermal and cooling temperatures in summer and winter, respectively.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"127 ","pages":"Article 104025"},"PeriodicalIF":2.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142846937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sex-specific differences in insulin response and substrate oxidation after repeated, brief whole-body immersion in 45 °C water: A prospective, interventional study","authors":"Rima Solianik,&nbsp;Gintare Dauksaite,&nbsp;Laura Jarutiene,&nbsp;Marius Brazaitis","doi":"10.1016/j.jtherbio.2024.104029","DOIUrl":"10.1016/j.jtherbio.2024.104029","url":null,"abstract":"<div><div>Prolonged heat exposure is suggested to improve glucose metabolism and fat oxidation, but no studies have addressed whether brief heat stimuli represent a viable, time-efficient, alternative approach. Consequently, we examined the ability of brief stimuli evoked by 45 °C water to improve glucose tolerance, insulin sensitivity, and fat oxidation in young, non-obese, males and females. Twenty-four participants completed fourteen 5-min sessions involving whole body passive heating in 45 °C water. Changes in resting catecholamines, cytokines, substrate oxidation, resting energy expenditure, glucose tolerance, and insulin release in response to an oral glucose tolerance test, were assessed before and 24-h after intervention, and 1 month after the end of the intervention. The results showed that repeated short-duration heat intervention had no significant effects on epinephrine, norepinephrine, interleukin-6, and tumor necrosis factor alpha production in both sexes. Glucose area under the curve (AUC) was not affected. However, females had a lower insulin AUC and improved insulin sensitivity as indicated by a decrease in homeostatic model assessment for insulin resistance, and an increase in the quantitative insulin sensitivity check index and the Matsuda insulin sensitivity index values one month after the end of the heat intervention. No effect was observed in resting energy expenditure, but carbohydrate oxidation per kilogram increased in females, and this substrate oxidation change was maintained after one month. In conclusion, fourteen sessions of brief 5-min whole-body immersion in 45 °C water produced an improvement in insulin sensitivity and increased reliance on carbohydrate oxidation in females.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"127 ","pages":"Article 104029"},"PeriodicalIF":2.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142846938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Embryological incubation temperature modulates behaviour in larval white sturgeon (Acispencer transmontanus)","authors":"Trevor J. Hamilton ,&nbsp;Katherine Cheung ,&nbsp;James Hudson ,&nbsp;Joshua Szaszkiewicz ,&nbsp;Erica Ingraham ,&nbsp;Jeffrey Krook ,&nbsp;Andréa Johnson ,&nbsp;Brian Franczak ,&nbsp;Steve McAdam ,&nbsp;Colin J. Brauner","doi":"10.1016/j.jtherbio.2025.104069","DOIUrl":"10.1016/j.jtherbio.2025.104069","url":null,"abstract":"<div><div>White sturgeon inhabit large rivers and estuaries along the Pacific coast of North America and play important ecological and cultural roles. As with other poikilotherms, the expected rise in global temperatures will create physiological challenges for sturgeon, including direct effects on physiological rates, and may also cause changes in behaviour that impact survival. In this study, we investigated ‘carryover effects’ in white sturgeon (<em>Acipenser transmontanus</em>) by incubating fish at one of three embryological temperatures (12 °C, 15 °C, or 18 °C) from fertilization to hatch, and then holding them at 15 °C for the following 30 days post-hatch (dph). We investigated the effect of these incubation temperatures on subsequent behaviours, including locomotion and anxiety-like behaviour, at 18, 24 and 30 dph. The open field test was used to quantify distance moved by the fish and time spent near the outer wall of the arena (to quantify thigmotaxis, an indicator of anxiety-like behaviour) and recorded with motion-tracking software. This test was also used to compare behaviour during the day versus night (at 21 dph) and hourly at night (at 28 dph). Additionally, a light/dark test commonly used in rodents and other fish species was performed for the first time on larval sturgeon at 24 dph. We found a significant family effect; the impact of embryo rearing temperature on locomotion and thigmotaxis varied depending on the family lineage of the fish. Furthermore, we provide evidence that larval sturgeon exhibit greater locomotion at 24 and 30 dph compared to 18 dph, and have a preference for the light zone of the light/dark test. Our findings identify a more nuanced effect of incubation temperature on later life stages that varies with family lineage and underscores the need to consider such variation in research and conservation programs.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"127 ","pages":"Article 104069"},"PeriodicalIF":2.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143372379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating the potential of geothermal heat pump and precision air supply system for heat stress abatement in dairy cattle barns","authors":"Yangyang Li ,&nbsp;Ran Ju ,&nbsp;Chongtao Liu ,&nbsp;Xiuping Tao ,&nbsp;Jianchao Song","doi":"10.1016/j.jtherbio.2024.104039","DOIUrl":"10.1016/j.jtherbio.2024.104039","url":null,"abstract":"<div><div>Maintaining an optimal indoor thermal environment is crucial for enhancing the welfare and productivity of livestock in intensive breeding farms. This paper investigated the application of a combined geothermal heat pump with a precision air supply (GHP-PAS) system for cooling dairy cows on a dairy farm. The effectiveness of the GHP-PAS system in mitigating heat stress in lactating dairy cattle, along with its energy performance and local cooling efficiency in the free stalls were evaluated. A total of 140 multiparous lactating Holstein cows was tested in two groups. One group was housed in a barn equipped with a GHP-PAS system (GP barn, n = 70), and the other was housed in a barn with a conventional fan-sprinkling system (FS barn, n = 70). Results showed that the ambient temperature of both GP and FS barns were lower than that outside the barn (<em>P</em> &lt; 0.05), with no significant difference between the GP and FS barns (<em>P</em> &gt; 0.05). Compared to cows in the FS barn, those in the GP barn exhibited lower skin temperature, rectal temperature, and respiratory rate (<em>P</em> &lt; 0.05). The mean temperature difference between outflow and inflow water was 2.56 °C of the GHP unit. The average energy efficiency ratios (EER) of the GHP unit and the GHP-PAS system were 5.03 and 2.92, respectively. The daily average electricity consumption was 20.4 ± 1.0 kWh. The field test results indicated that the airflow from a single nozzle of the GHP-PAS system effectively covered a stall space with an average width of 1.84 m at a cow reclining height of 0.5 m, with an average air velocity of 1 m/s. The per-cow hourly electricity consumption for cooling was 2.04 kWh for the GHP-PAS system and 0.36 kWh for the FS system, highlighting that the GHP-PAS system is approximately 5.6 times more energy-intensive than the FS system. In conclusion, the GHP-PAS system showed the potential for alleviating heat stress in dairy cows. Further research is needed to enhance the energy efficiency and cooling effectiveness of the current GHP-PAS system.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"127 ","pages":"Article 104039"},"PeriodicalIF":2.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142983984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spawning is accompanied by increased thermal performance in blue mussels","authors":"Katharina Alter ,&nbsp;Maria Constenla ,&nbsp;Francesc Padrós ,&nbsp;Inna M. Sokolova ,&nbsp;Ana Born-Torrijos","doi":"10.1016/j.jtherbio.2024.104018","DOIUrl":"10.1016/j.jtherbio.2024.104018","url":null,"abstract":"<div><div>Climate change is causing extreme short-term warming with greater intensity and more frequent occurrence. Reproduction and subsequent recruitment of coastal ecosystem engineers, such as the blue mussel, may be impacted by the extreme temperatures because these vital functions are sensitive to the timing of short-term changes in abiotic factors. We exposed intertidal blue mussels, <em>Mytilus edulis,</em> to a thermal challenge from 10 to 29 °C using an ecologically relevant heating rate of 4 °C/h. We assessed their reproductive status by observing spawning activity and by analyzing histological sections of their gonad tissue. In addition, we monitored their heart rates and valve gaping behavior to determine their thermal performance. We identified three spawning groups: non-spawners that had mature gonads but did not release gametes, post-spawners that released mature gametes prior to the thermal challenge, and active spawners that released mature gametes during the thermal challenge. Across temperatures, active spawners had significantly higher heart rates and their heart rate peaked at the temperatures 3.9 and 3.2 °C higher compared to those of non-spawners or post-spawners, respectively. Post-spawners had significantly narrower valve gapes across temperatures compared to both other spawning groups. Hence, the metabolic response to warming strongly depends on the reproductive status, with active spawners experiencing increased thermal stress due to heightened metabolism, non-spawners showing heat-induced metabolic depression, and post-spawners adopting an energy-conserving strategy indicated by reduced gaping. Considered together, spawning during recurring short-term warming events may elevate mortality risk with potential consequences for the local biodiversity in a future climate.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"127 ","pages":"Article 104018"},"PeriodicalIF":2.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142872250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of life stage and season in critical thermal limits of carrion beetles","authors":"Chloe F. Garfinkel ,&nbsp;Christy M. McCain","doi":"10.1016/j.jtherbio.2025.104063","DOIUrl":"10.1016/j.jtherbio.2025.104063","url":null,"abstract":"<div><div>Larval and winter thermal limits may be vital for understanding responses to climate variability, but many studies of insect critical thermal limits focus on adults reared in benign conditions (lab or summer field conditions). For insects generally, temperature variability and thermal tolerance breadth are correlated. Thus, we predict broader thermal limits in adults compared to less-mobile larvae developing within a restricted microclimate. We also predict lower cold limits in winter adults compared to summer adults. To test for this thermal variability across life stages and seasons, we used a recirculating bath to determine critical thermal limits in two species of Colorado carrion beetles (Coleoptera: Staphylinidae: Silphinae) in which larvae develop within a carcass microclimate. For larval and adult comparisons, we used summer <em>Thanatophilus lapponicus</em> (n = 111) and <em>Thanatophilus coloradensis</em> (n = 46). For winter and summer comparisons, we used adult <em>T. lapponicus</em> (n = 103). We detected no difference between larvae and adults in <em>T. lapponicus</em> for either upper thermal limits (CTmax) or lower thermal limits (CTmin) for wild caught adults, bred larvae, and bred adults. In contrast, wild caught adults of <em>T. coloradensis</em> had a significantly lower CTmin (−5.7 ± 0.5 °C) compared to wild caught larvae (−3.0 ± 1.3 °C) and bred larvae (−3.5 ± 0.8 °C) with no difference in CTmax. Winter <em>T. lapponicus</em> adults displayed a nearly one-degree lower CTmin (−2.8 ± 1.6 °C) than summer adults (−1.9 ± 1.9 °C) with no difference in CTmax. These results demonstrate that even closely related, co-occurring species can have distinct strategies for coping with cold temperatures. And, in some cases, particularly for high-elevation specialists, larvae may benefit from a temperature-buffered microclimate. Heat tolerance was broad and less variable across life stages and seasons, emphasizing that variation in cold temperatures will be critical for responses to climate change, for example, changes in snow levels impacting insulation.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"127 ","pages":"Article 104063"},"PeriodicalIF":2.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143181564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is skin temperature associated with training load during preparatory period of a professional volleyball team?","authors":"Thiago Seixas Duarte ,&nbsp;João B. Ferreira-Júnior ,&nbsp;Jeann C.G. Oliveira ,&nbsp;Carlos M.A. Costa ,&nbsp;Daniel B. Coelho ,&nbsp;João C.B. Marins ,&nbsp;Maurício G. Bara-Filho","doi":"10.1016/j.jtherbio.2024.104038","DOIUrl":"10.1016/j.jtherbio.2024.104038","url":null,"abstract":"<div><div>The current study investigated if skin temperature (Tsk) measurement through infrared thermography could reflect the accumulation of training load during the preparatory period of a professional volleyball team. Sixteen athletes (20.1 ± 3.1 years, 88.1 ± 6.1 kg, 193 ± 0.1 cm e 13.3 ± 2.3 % body fat) were assessed over two weeks of the preparatory period (5 training days in each week) for the second division of the Brazilian Men's Volleyball Super League. After one week of familiarization with the study procedures, Tsk was measured in eight regions (anterior and posterior areas of arm, shoulder, thigh, and leg) on the first and last training days of each week, along with perceived recovery status (PRS) were measured on the first and last training days of each week. Training load for each session and total weekly training load (TWTL) were calculated using the session rating of perceived exertion (SRPE) method. Three days in the first week and four days in the second week had higher training loads (χ² = 89.1, p &lt; 0.001), as indicated by a significant reduction in recovery perception at the end of each week (F = 52.3, p &lt; 0.001). Among the eight regions examined, five showed a decrease in Tsk after two rest days (weekend), while two regions exhibited an increase in Tsk at the end of the following training week (p &lt; 0.05). Out of 44 associations examined between Tsk, PRS, and TWTL, only the associations between delta PRS and delta mean Tsk of the anterior and posterior leg were significant (β = −0.20, p &lt; 0.045 for both). In conclusion, the data suggest that Tsk may be altered during the pre-competitive period of professional volleyball players; however, it does not appear to be associated with PRS and training load as assessed by the SRPE method.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"127 ","pages":"Article 104038"},"PeriodicalIF":2.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143181566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Individual variation in diurnal body temperature and foraging activity in overwintering black-capped chickadees (Poecile atricapillus)","authors":"Deborah M. Hawkshaw ,&nbsp;Jan J. Wijmenga ,&nbsp;Kimberley J. Mathot","doi":"10.1016/j.jtherbio.2025.104059","DOIUrl":"10.1016/j.jtherbio.2025.104059","url":null,"abstract":"<div><div>Small birds in winter can mitigate energetic shortfalls via increases in foraging and/or via controlled reductions in metabolic rate and body temperature (torpor). The ability to both increase foraging and use torpor during the day could have profound implications for an individual's daily energy budget and overwinter survival. Trade-offs between foraging efficiency and daytime torpor use may exist but have not been explicitly investigated. Here, we investigated the presence of within- and among-individual correlations between daytime body temperature (T_b, a proxy for torpor use) and foraging in overwintering black-capped chickadees (<em>Poecile atricapillus</em>). Using temperature-sensing passive integrated transponder tags, we measured daytime T_b and foraging in 20 free-living chickadees over 49 days in a single winter (January–February). Chickadees generally exhibited T_b around normothermic levels with an average T_b during visits to the feeder of 41.7 °C, though T_b ranged between 25.0 and 44.9 °C. Chickadees exhibited moderately lower daytime T_b, shorter time intervals between successive feeder visits (IVI), and increased feeder visits as ambient temperature decreased. However, within individuals there was only evidence of a weak positive correlation between visit T_b and IVI, and no correlation between daily feeder visits and daily mean visit T_b. We found that visit T_b, daily mean visit T_b_, and daily feeder visits were repeatable, while IVI was not. Sex did not explain a significant amount of variation in total daily feeder visits or daytime T_b, nor was there evidence of among-individual correlations between daily mean visit T_b and daily feeder visits. Our results suggests that chickadees may independently regulate foraging and diurnal T_b. Overall, our study provides insights into how small birds in winter can use multiple strategies to overcome energetic challenges. Future studies investigating diurnal torpor and its integration with other strategies are needed to further elucidate how small birds survive harsh winter conditions.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"127 ","pages":"Article 104059"},"PeriodicalIF":2.9,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143074893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}