Adapting to stress: The effects of hibernation and hibernacula temperature on the hepatic transcriptome of Rhinolophus pusillus.

Hibernation, a survival strategy in mammals for extreme climates, induces physiological phenomena such as ischemia-reperfusion and metabolic shifts that hold great potential for advancements in modern medicine. Despite this, the molecular mechanisms underpinning hibernation remain largely unclear. This study used RNA-seq and Iso-seq techniques to investigate the changes in liver transcriptome expression of Rhinolophus pusillus during hibernation and active periods, as well as under different microhabitat temperatures. We identified 11 457 differentially expressed genes during hibernation and active periods, of which 395 showed significant differential expression. Genes associated with fatty acid catabolism were significantly upregulated during hibernation, whereas genes related to carbohydrate metabolism and glycogen synthesis were downregulated. Conversely, immune-related genes displayed differential expression patterns: genes tied to innate immunity were significantly upregulated, while those linked to adaptive immunity and inflammatory response were downregulated. The analysis of transcriptomic data obtained from different microhabitat temperatures revealed that R. pusillus exhibited an upregulation of genes associated with lipid metabolism in lower microhabitat temperature. This upregulation facilitated an enhanced utilization rate of triglyceride, ultimately resulting in increased energy provision for the organism. Additionally, R. pusillus upregulated gluconeogenesis-related genes regardless of the microhabitat temperature, demonstrating the importance of maintaining blood glucose levels during hibernation. Our transcriptomic data reveal that these changes in liver gene expression optimize energy allocation during hibernation, suggesting that liver tissue adaptively responds to the inherent stress of its function during hibernation. This study sheds light on the role of differential gene expression in promoting more efficient energy allocation during hibernation. It contributes to our understanding of how liver tissue adapts to the stressors associated with this state.

Competitive Displacement and Agonistic Character Displacement, or the Ghost of Interference Competition.

AbstractInterference competition can drive species apart in habitat use through competitive displacement in ecological time and agonistic character displacement (ACD) over evolutionary time. As predicted by ACD theory, sympatric species of rubyspot damselflies (Hetaerina spp.) that respond more aggressively to each other in staged encounters differ more in microhabitat use. However, the same pattern could arise from competitive displacement if dominant species actively exclude subordinate species from preferred microhabitats. The degree to which habitat partitioning is caused by competitive displacement can be assessed with removal experiments. We carried out removal experiments with three species pairs of rubyspot damselflies. With competitive displacement, removing dominant species should allow subordinate species to shift into the dominant species' microhabitat. Instead, we found that species-specific microhabitat use persisted after the experimental removals. Thus, the previously documented association between heterospecific aggression and microhabitat partitioning in this genus is most likely a product of divergence in habitat preferences caused by interference competition in the evolutionary past.

Parallel shifts in flight-height associated with altitude across incipient Heliconius species.

Vertical gradients in microclimate, resource availability, and interspecific interactions are thought to underly stratification patterns in tropical insect communities. However, only a few studies have explored the adaptive significance of vertical space use during the early stages of reproductive isolation. We analysed flight-height variation across speciation events in Heliconius butterflies, representing parallel colonizations of high-altitude forest. We measured flight-height in wild H. erato venus and H. chestertonii, parapatric lowland and mountain specialists, respectively, and found that H. chestertonii consistently flies at a lower height. By comparing our data to previously published results for the ecologically equivalent H. e. cyrbia (lowland) and H. himera (high altitude), we found that the species flying closest to the ground are those that recently colonized high-altitude forests. We show that these repeated trends largely result from shared patterns of ecological selection producing parallel trait-shifts in H. himera and H. chestertonii. Although our results imply a signature of local adaptation, we did not find an association between resource distribution and flight-height in H. e. venus and H. chestertonii. We discuss how this pattern may be explained by variations in forest structure and microclimate. Overall, our findings underscore the importance of behavioural adjustments during early divergence mediated by altitude-shifts.

Decoupled evolution of ventral and dorsal scales in agamid lizards: ventral keels are associated with arboreality.

Arboreality has evolved in all major vertebrate lineages and is often associated with morphological adaptations and increased diversification concomitant with accessing novel niche space. In squamate reptiles, foot, claw, and tail morphology are well-studied adaptations shown to be associated with transitions to arboreality. Here, we examined a less well understood trait-the keeled scale-in relation to microhabitat, climate, and diversification dynamics across a diverse lizard radiation, Agamidae. We found that the ancestral agamid had keeled dorsal but not ventral scales; further, dorsal and ventral keels are evolutionarily decoupled. Ventral keeled scales evolved repeatedly in association with arboreality and may be advantageous in reducing wear or by promoting interlocking when climbing. We did not find an association between keeled scales and diversification, suggesting keels do not allow finer-scale microhabitat partitioning observed in other arboreal-associated traits. We additionally found a relationship between keeled ventral scales and precipitation in terrestrial species where we posit that the keels may function to reduce scale degradation. Our results suggest that keeled ventral scales facilitated transitions to arboreality across agamid lizards, and highlight a need for future studies that explore their biomechanical function in relation to microhabitat and climate.

Ticks - public health risks in urban green spaces.

BACKGROUND: Urban green spaces are important for human health, but they may expose visitors to tick-borne diseases. This not only presents a potential public health challenge but also undermines the expected public health gains from urban green spaces. The aim of this study is to assess the public health risk of tick-borne diseases in an urban green space used for recreation in Stockholm, Sweden. METHODS: We used a mixed method approach identifying both the magnitude of the tick hazard and the extent of the human exposure to tick-borne diseases. At six entry points to an urban green space, we sampled ticks and documented microhabitat conditions from five randomly assigned 2 m × 2 m plots. Surrounding habitat data was analyzed using geographical information system (GIS). Nymphs and adult ticks were tested for Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum using TaqMan qPCR. Positive B. burgdorferi (s.l.) ticks were further analyzed by nested PCR amplification and sequence analysis. Population census data and visitor count data were used to estimate the degree of human exposure to tick-borne diseases. To further understand the degree to which visitors get in contact with infected ticks we also conducted interviews with visitors to green spaces. RESULTS: High tick densities were commonly found in humid broadleaved forest with low field vegetation. High pathogen prevalence was significantly correlated with increasing proportions of artificial areas. Integrating the tick hazard with human exposure we found that the public health risk of tick-borne diseases was moderate to high at most of the studied entry points. Many of the visitors frequently used urban green spaces. Walking was the most common activity, but visitors also engaged in activities with higher risk for tick encounters. Individual protective measures were connected to specific recreational activities such as picking berries or mushrooms. CONCLUSIONS: The number of visitors can be combined with tick inventory data and molecular analyses of pathogen prevalence to make crude estimations of the public health risk of tick-borne diseases in urban green spaces. The risk of encountering infected ticks is omnipresent during recreational activities in urban green spaces, highlighting the need for public health campaigns to reduce the risk of tick-borne diseases.

Behavioral thermoregulation in primates: A review of literature and future avenues.

Primates face severe challenges from climate change, with warming expected to increase animals' thermoregulatory demands. Primates have limited long-term options to cope with climate change, but possess a remarkable capacity for behavioral plasticity. This creates an urgency to better understand the behavioral mechanisms primates use to thermoregulate. While considerable information exists on primate behavioral thermoregulation, it is often scattered in the literature in a manner that is difficult to integrate. This review evaluates the status of the available literature on primate behavioral thermoregulation to facilitate future research. We surveyed peer-reviewed publications on primate thermoregulation for N = 17 behaviors across four thermoregulatory categories: activity budgeting, microhabitat use, body positioning, and evaporative cooling. We recorded data on the primate taxa evaluated, support for a thermoregulatory function, thermal variable assessed, and naturalistic/manipulative study conditions. Behavioral thermoregulation was pervasive across primates, with N = 721 cases of thermoregulatory behaviors identified across N = 284 published studies. Most genera were known to utilize multiple behaviors ( x ¯ = 4.5 ± 3.1 behaviors/genera). Activity budgeting behaviors were the most commonly encountered category in the literature (54.5% of cases), while evaporative cooling behaviors were the least represented (6.9% of cases). Behavioral thermoregulation studies were underrepresented for certain taxonomic groups, including lemurs, lorises, galagos, and Central/South American primates, and there were large within-taxa disparities in representation of genera. Support for a thermoregulatory function was consistently high across all behaviors, spanning both hot- and cold-avoidance strategies. This review reveals asymmetries in the current literature and avenues for future research. Increased knowledge of the impact thermoregulatory behaviors have on biologically relevant outcomes is needed to better assess primate responses to warming environments and develop early indicators of thermal stress.

Genome evolution of the psammophyte Pugionium for desert adaptation and further speciation.

Deserts exert strong selection pressures on plants, but the underlying genomic drivers of ecological adaptation and subsequent speciation remain largely unknown. Here, we generated de novo genome assemblies and conducted population genomic analyses of the psammophytic genus Pugionium (Brassicaceae). Our results indicated that this bispecific genus had undergone an allopolyploid event, and the two parental genomes were derived from two ancestral lineages with different chromosome numbers and structures. The postpolyploid expansion of gene families related to abiotic stress responses and lignin biosynthesis facilitated environmental adaptations of the genus to desert habitats. Population genomic analyses of both species further revealed their recent divergence with continuous gene flow, and the most divergent regions were found to be centered on three highly structurally reshuffled chromosomes. Genes under selection in these regions, which were mainly located in one of the two subgenomes, contributed greatly to the interspecific divergence in microhabitat adaptation.

Sharks checking in to the sponge hotel: First internal use of sponges of the genus Agelas and family Irciniidae by banded sand catsharks Atelomycterus fasciatus.

Trawl surveys within and surrounding two northwestern Australian marine parks revealed banded sand catsharks Atelomycterus fasciatus (family Atelomycteridae) taking refuge within large sponges of the family Irciniidae (Demospongiae: Dictyoceratida) and the genus Agelas (Demospongiae: Agelasida: Agelasidae). Five sponges contained a total of 57 A. fasciatus, comprising both sexes and both immature and mature individuals ranging from 102 to 390 mm total length (TL). In the same surveys, only five A. fasciatus were captured unassociated with sponges, suggesting that sponges are an important microhabitat for A. fasciatus and may provide a daytime refuge from predators. A southerly range extension is also reported for this species.

Bird nesting boxes as a specific artificial microenvironment increasing biodiversity of mites from the suborder Uropodina (Acari: Mesostigmata): a case study of Bory Tucholskie National Park.

Bory Tucholskie National Park, founded in 1996, is one of the most recently established national parks in Poland, and therefore, has not been thoroughly examined yet. The authors of the current study present results of their research concerning communities of mites from the suborder Uropodina (Acari: Mesostigmata), inhabiting bird nesting boxes within the area of Bory Tucholskie National Park. The mite community comprises two nidicolous species, i.e. Leiodinychus orbicularis (C.L. Koch, 1839) and Chiropturopoda nidiphila (Wisniewski and Hirschmann 1993). The former is a species characteristic of various types of nests, as well as nesting boxes, where it is usually the eudominant species. The latter is an extremely rare and scarce species of Uropodina, known thus far from woodpeckers' hollows. The population of L. orbicularis in the analysed communities in the realm of Bory Tucholskie National Park has been estimated to be over 6,000 specimens, and in the case of Ch. nidiphila - over 400 specimens.

Shining a light on species coexistence: visual traits drive bumblebee communities.

Local coexistence of bees has been explained by flower resource partitioning, but coexisting bumblebee species often have strongly overlapping diets. We investigated if light microhabitat niche separation, underpinned by visual traits, could serve as an alternative mechanism underlying local coexistence of bumblebee species. To this end, we focused on a homogeneous flower resource-bilberry-in a heterogeneous light environment-hemi-boreal forests. We found that bumblebee communities segregated along a gradient of light intensity. The community-weighted mean of the eye parameter-a metric measuring the compromise between light sensitivity and visual resolution-decreased with light intensity, showing a higher investment in light sensitivity of communities observed in darker conditions. This pattern was consistent at the species level. In general, species with higher eye parameter (larger investment in light sensitivity) foraged in dimmer light than those with a lower eye parameter (higher investment in visual resolution). Moreover, species realized niche optimum was linearly related to their eye parameter. These results suggest microhabitat niche partitioning to be a potential mechanism underpinning bumblebee species coexistence. This study highlights the importance of considering sensory traits when studying pollinator habitat use and their ability to cope with changing environments.

Mismatches between phenotype and environment shape fitness at hyperlocal scales.

In the era of human-driven climate change, understanding whether behavioural buffering of temperature change is linked with organismal fitness is essential. According to the 'cost-benefit' model of thermoregulation, animals that live in environments with high frequencies of favourable thermal microclimates should incur lower thermoregulatory costs, thermoregulate more efficiently and shunt the associated savings in time and energy towards other vital tasks such as feeding, territory defence and mate acquisition, increasing fitness. Here, we explore how thermal landscapes at the scale of individual territories, physiological performance and behaviour interact and shape fitness in the southern rock agama lizard (Agama atra). We integrated laboratory assays of whole organism performance with behavioural observations in the field, fine-scale estimates of environmental temperature, and paternity assignment of offspring to test whether fitness is predicted by territory thermal quality (i.e. the number of hours that operative temperatures in a territory fall within an individual's performance breadth). Male lizards that occupied territories of low thermal quality spent more time behaviourally compensating for sub-optimal temperatures and displayed less. Further, display rate was positively associated with lizard fitness, suggesting that there is an opportunity cost to engaging in thermoregulatory behaviour that will change as climate change progresses.

Microhabitat conditions remedy heat stress effects on insect activity.

Anthropogenic global warming has major implications for mobile terrestrial insects, including long-term effects from constant warming, for example, on species distribution patterns, and short-term effects from heat extremes that induce immediate physiological responses. To cope with heat extremes, they either have to reduce their activity or move to preferable microhabitats. The availability of favorable microhabitat conditions is strongly promoted by the spatial heterogeneity of habitats, which is often reduced by anthropogenic land transformation. Thus, it is decisive to understand the combined effects of these global change drivers on insect activity. Here, we assessed the movement activity of six insect species (from three orders) in response to heat stress using a unique tracking approach via radio frequency identification. We tracked 465 individuals at the iDiv Ecotron across a temperature gradient up to 38.7°C. In addition, we varied microhabitat conditions by adding leaf litter from four different tree species to the experimental units, either spatially separated or well mixed. Our results show opposing effects of heat extremes on insect activity depending on the microhabitat conditions. The insect community significantly decreased its activity in the mixed litter scenario, while we found a strong positive effect on activity in the separated litter scenario. We hypothesize that the simultaneous availability of thermal refugia as well as resources provided by the mixed litter scenario allows animals to reduce their activity and save energy in response to heat stress. Contrary, the spatial separation of beneficial microclimatic conditions and resources forces animals to increase their activity to fulfill their energetic needs. Thus, our study highlights the importance of habitat heterogeneity on smaller scales, because it may buffer the consequences of extreme temperatures of insect performance and survival under global change.

Unraveling the importance of functionally extreme tadpole types to functional diversity: a case study in temperate montane streams.

BACKGROUND: Functional diversity is important to maintain ecosystem functioning. Species with different ecomorphological traits may display distinct functional roles in ecosystems. Accordingly, functionally extreme species are more important as they can exhibit specific strategies. However, little is known about the distribution patterns of functionally extreme species at a local scale and whether the prior extinction of extreme species can cause significant effects on functional diversity. In addition, no empirical studies have been conducted on the microhabitat determinants of extreme species to maintain the functional diversity. RESULTS: This study collected 1470 tadpoles belonging to 6 families and 20 anuran species. These species were subsequently divided into 65 functional entities based on their developmental stages to incorporate intraspecific traits variability. As a result, we detected seven extreme functional entities, accounting for 10.7% of the total number of entities. Moreover, the prior extinction of extreme entities can lead to a significant decrease in functional diversity compared with the random extinction of entities. Microhabitat variables such as conductivity, water depth, and current velocity determined the distribution of extreme entities. CONCLUSION: Although the functionally extreme entities only represented a small proportion of the total number of tadpoles, they played irreplaceable roles in maintaining functional diversity. Their extinction may induce high functional vulnerability in tadpole communities. Therefore, anuran species with extreme tadpole traits need to be projected for amphibian conservation.

Of corpses, ghosts and mirages: biomechanical consequences of morphology depend on the environment.

Organisms are subject to the laws of physics, so comparative biomechanics is a powerful approach for identifying basic principles that apply across taxa of how morphology affects performance of mechanical functions such as locomotion, feeding or resisting damage. Journal of Experimental Biology has been a leading journal for decades in publishing studies revealing such basic biomechanical principles. However, field studies of the physical environment, ecological interactions and life-history strategies of organisms reveal which aspects of their biomechanical performance are important to their success in different types of natural habitats, and thus enable us to design ecologically relevant laboratory experiments to understand biomechanical function. Because the fitness consequences of differences in morphology are affected by the biological and physical environment, biomechanics can be used to identify how physical constraints on the performance of organisms with different body plans in variable environments can affect evolution. I illustrate these points with examples from the literature that show how the biomechanical consequences of morphology depend on the ecology of the organisms. Knowledge of the temporal patterns of interactions of organisms with their physical and biological environments is essential for understanding their functional morphology as it changes during ontogeny, and it reveals constraints on their evolution.

Community form, function and phylogenetic diversity respond differently across microhabitat and recovery gradients.

Research Highlight: Hoenle, P. O., Staab, M., Donoso, D. A., Argoti, A., & Blüthgen, N. (2023). Stratification and recovery time jointly shape ant functional reassembly in a neotropical forest. Journal of Animal Ecology, https://doi.org/10.1111/1365-2656.13896. Space, time and abiotic variation are primary axes across investigations of community ecology and disturbed ecosystems offer tractable systems for assessing their relative impact. While recovering forests can act as isolated case studies in understanding community assembly, it is not well understood how individual microhabitats respond to recovery and ultimately shape community attributes. Hoenle et al. (2023) leverage the ubiquity and microhabitat-specific diversity of ants across a gradient from active agricultural sites to old-growth forest and assess how recovery and stratification together shape communities. The authors find distinct stratification across phylogenetic, functional and trait diversity as forest recovery time increases, while also recovering unique recovery trajectories contingent on trait sampling. While stratified, phylogenetic and functional diversity did not increase along this recovery gradient. Ten out of 13 sampled traits were jointly influenced by both stratification and recovery time. In contrast to intuitive predictions, a majority of trait means converged throughout the recovery period. Results highlight the multifaceted nature of recovery-based community assembly and the capacity of multidimensional sampling to uncover surprising patterns in ecologically diverse lineages.

Community recovery of benthic macroinvertebrates in a stream influenced by mining activity: Importance of microhabitat monitoring.

The decrease in freshwater biodiversity owing to anthropogenic disturbances such as mining activity is a global challenge; hence, there is an urgent need for systematic approaches to continuously monitor such disturbances and/or the recovery of biodiversity in freshwater habitats. The Hwangjicheon Stream is the source of South Korea's longest river and has been subjected to runoff from coal mining. We investigated changes in the diversity of the benthic macroinvertebrate community in various microhabitats, including riffle, run, and pool, to monitor the recovery of biodiversity in the stream following the improvement of a mining water treatment plant in 2019. The dataset comprised 111 samples obtained from four types of microhabitats (riffle, run, pool, and riparian) over a four-year period from 2018 to 2021. The mining-affected sites had lower macroinvertebrate community complexities according to a network analysis, and grouped into the same cluster based on self-organizing map (SOM) analysis. Moreover, 51 taxa selected as indicator species represented each cluster obtained through the SOM analysis. Among them, only Limnodrilus gotoi and Radix auricularia were included as indicator species at the mining-affected sites. However, after 2020, the benthic macroinvertebrate community complexity increased, and some of the microhabitats at the mining-affected sites were included in the same cluster as the reference sites in the SOM analysis, indicating that the recovery of benthic macroinvertebrate communities had initiated in certain microhabitats (e.g., riparian). Further analysis confirmed that the macroinvertebrate community clearly differed according to the survey year, even in different microhabitats at the same sites. This suggests that more acute microhabitat monitoring may be necessary to quickly confirm biodiversity restoration when assessing the degree of the recovery in river biodiversity from anthropogenic disturbances.

Surviving hot summer: Roles of phenotypic plasticity of intertidal mobile species considering microhabitat environmental heterogeneity.

For species inhabiting warming and variable thermal environment, coordinated changes in heat tolerance to temperature fluctuations, which largely depend on phenotypic plasticity, are pivotal in buffering high temperatures. Determining the roles of phenotypic plasticity in wild populations and common garden experiments help us understand how organisms survive hot summer and the warming world. We thus monitored the operative temperature of the intertidal limpets Cellana toreuma in both emergent rock and tidal pool microhabitats from June to October 2021, determined the variations of upper thermal limits of short-term acclimated and long-term acclimated limpets from different microhabitats (emergent rock and tidal pool), and further calculated the relationship between the upper thermal limits and acclimation capacity. Our results indicated that living on the emergent rock, limpets encountered more extreme events in summer. For the short-term acclimated samples, limpets on the emergent rock exhibited obvious variations of sublethal thermal limit (i.e., Arrhenius Break Point of cardiac performance, ABT) during summer months, however, this variation of ABT was absent in the limpets in the tidal pool. After the laboratory long-term acclimation, the ABTs and FLTs (Flat Line Temperature of cardiac performance, as an indicator of lethal temperature) of limpets both on the rock and in the tidal pool increased significantly in October, implying the potential existence of selection during the hot summer. Our results further showed that environmental temperature was an important driver of phenotypic plasticity. This study highlighted the changes in the thermal tolerance of intertidal limpets during summer in different microhabitats.

Lethal and sublethal implications of low temperature exposure for three intertidal predators.

Benthic invertebrate predators play a key role in top-down trophic regulation in intertidal ecosystems. While the physiological and ecological consequences of predator exposure to high temperatures during summer low tides are increasingly well-studied, the effects of cold exposure during winter low tides remain poorly understood. To address this knowledge gap, we measured the supercooling points, survival, and feeding rates of three intertidal predator species in British Columbia, Canada - the sea stars Pisaster ochraceus and Evasterias troschelii and the dogwhelk Nucella lamellosa - in response to exposure to sub-zero air temperatures. Overall, we found that all three predators exhibited evidence of internal freezing at relatively mild sub-zero temperatures, with sea stars exhibiting an average supercooling point of -2.50 °C, and the dogwhelk averaging approximately -3.99 °C. None of the tested species are strongly freeze tolerant, as evidenced by moderate-to-low survival rates after exposure to -8 °C air. All three predators exhibited significantly reduced feeding rates over a two-week period following a single 3-h sublethal (-0.5 °C) exposure event. We also quantified variation in predator body temperature among thermal microhabitats during winter low tides. Predators that were found at the base of large boulders, on the sediment, and within crevices had higher body temperatures during winter low tides, as compared to those situated in other microhabitats. However, we did not find evidence of behavioural thermoregulation via selective microhabitat use during cold weather. Since these intertidal predators are less freeze tolerant than their preferred prey, winter low temperature exposures can have important implications for organism survival and predator-prey dynamics across thermal gradients at both local (habitat-driven) and geographic (climate-driven) scales.

Assessing The Effectiveness of Rainwater Harvesting Systems In Improving Wintering Bird Richness In Pre-Saharan Tunisia.

The impact of rainwater harvesting systems on biodiversity in hyperarid North African areas has not been assessed to date despite its demonstrated usefulness. The present study investigated this impact by considering the richness of wintering birds (RWB) in the Tataouine region (pre-Saharan Tunisia). We used data from three sets of variables-rainwater harvesting system type, microhabitat conditions, and topography-to determine the best predictors causing variation in the RWB by means of generalized linear mixed models. Our results show that the jessour system is the most attractive for the wintering bird species, followed by the tabia system, and lastly by the control areas. In the jessour system, RWB is influenced positively by slope and shrub cover and quadratically by tree cover, whereas this richness is affected positively by the extent of the herbaceous layer in the tabia system. In the control areas, RWB is negatively affected by elevation and quadratically affected by tree cover. Variation partitioning (VP) analysis reveals that (i) space is the most robust factor explaining the RWB in control areas (adj. R2 = 0.15, p = 0.001), (ii) microhabitat is central in the tabia system (adj. R2 = 0.10, p = 0.001), and (iii) the shared fraction between microhabitat and space is relevant in the jessour systems (adj. R2 = 0.20). Specific management actions, especially preserving, maintaining, and promoting these traditional systems, are suggested to improve the attraction of wintering bird species to the Tataouine region. The implementation of a scientific watch system is recommended to understand how changes take place in such an arid environment.

Climate-associated decline of body condition in a fossorial salamander.

Temperate ectotherms have responded to recent environmental change, likely due to the direct and indirect effects of temperature on key life cycle events. Yet, a substantial number of ectotherms are fossorial, spending the vast majority of their lives in subterranean microhabitats that are assumed to be buffered against environmental change. Here, we examine whether seasonal climatic conditions influence body condition (a measure of general health and vigor), reproductive output, and breeding phenology in a northern population of fossorial salamander (Spotted Salamander, Ambystoma maculatum). We found that breeding body condition declined over a 12-year monitoring period (2008-2019) with warmer summer and autumn temperatures at least partly responsible for the observed decline in body condition. Our findings are consistent with the hypothesis that elevated metabolism drives the negative association between temperature and condition. Population-level reproduction, assessed via egg mass counts, showed high interannual variation and was weakly influenced by autumn temperatures. Salamander breeding phenology was strongly correlated with lake ice melt but showed no long-term temporal trend (1986-2019). Climatic warming in the region, which has been and is forecasted to be strongest in the summer and autumn, is predicted to lead to a 5%-27% decline in salamander body condition under realistic near-future climate scenarios. Although the subterranean environment offers a thermal buffer, the observed decline in condition and relatively strong effect of summer temperature on body condition suggest that fossorial salamanders are sensitive to the effects of a warming climate. Given the diversity of fossorial taxa, heightened attention to the vulnerability of subterranean microhabitat refugia and their inhabitants is warranted amid global climatic change.