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Termites are key components of tropical ecosystems, particularly in the Cerrado biome, where they dominate animal biomass and play crucial roles in nutrient cycling and soil formation. Their abundance and nutritional value make them primary food sources for various Cerrado animals, influencing predator diversity and several ecological interactions. Additionally, termite mounds serve as essential shelters for a wide range of fauna, aiding in thermoregulation and providing refuge from harsh environmental conditions, including wildfires. In this scenario, termitaria survival, diversity, and availability have several effects on the Cerrado fauna ecology. We present novel insights into the interaction between Actinobolus beetles and epigeous termite mounds in the Cerrado. Our field observations revealed Actinobolus beetles utilizing termite mounds for feeding and reproduction in several localities of Cerrado. These beetles access the inner portion of the termitaria, where the colony nest is located and protected by the termitaria's harder external layer and their larvae consume the termite nest structure. Actinobolus attack leads to partial or complete destruction of the colony and the creation of large hollows inside the mounds, causing deep changes in its structure. Despite the defensive mechanisms of termites, Actinobolus larvae thrive within the nest and likely ingest termites' eggs, nymphae and adults. Furthermore, we found that the Actinobolus capsule are made of faecal pellets, instead of termitaria debris. We suggest that the interaction between Actinobolus beetles and epigeous termitaria impacts the role of termitaria in providing microclimate regulation, food and shelter for Cerrado fauna, likely having poorly understood effects on the conservation and management of Cerrado ecosystems. [ABSTRACT FROM AUTHOR]

Nitrogen (N) deposition from agriculture and combustion of fossil fuels is a major threat to plant diversity, but its effects on organisms at higher trophic levels are unclear. We investigated how N deposition may affect species richness and abundance (number of individuals per species) in butterflies. We reviewed the peer‐reviewed literature on variables used to explain spatial variation in butterfly species richness and found that vegetation variables appeared to be as important as climate and habitat variables in explaining butterfly species richness. It thus seemed likely that increased N deposition could indirectly affect butterfly communities via its influence on plant communities. To test this prediction, we analyzed data from the Swiss biodiversity monitoring program for vascular plants and butterflies in 383 study sites of 1 km2 that are evenly distributed throughout Switzerland. The area has a modeled N deposition gradient of 2–44 kg N ha−1 year−1. We used traditional linear models and structural equation models to infer the drivers of the spatial variation in butterfly species richness across Switzerland. High N deposition was consistently linked to low butterfly diversity, suggesting a net loss of butterfly diversity through increased N deposition. We hypothesize that at low elevations, N deposition may contribute to a reduction in butterfly species richness via microclimatic cooling due to increased plant biomass. At higher elevations, negative effects of N deposition on butterfly species richness may also be mediated by reduced plant species richness. In most butterfly species, abundance was negatively related to N deposition, but the strongest negative effects were found for species of conservation concern. We conclude that in addition to factors such as intensified agriculture, habitat fragmentation, and climate change, N deposition is likely to play a key role in negatively affecting butterfly diversity and abundance. Article impact statement: Nitrogen deposition negatively affects butterfly species richness and butterfly abundance, particularly in species of conservation concern. [ABSTRACT FROM AUTHOR]

Aim: Microclimate information is often crucial for understanding ecological patterns and processes, including under climate change, but is typically absent from ecological and biogeographic studies owing to difficulties in obtaining microclimate data. Recent advances in microclimate modelling, however, suggest that microclimate conditions can now be predicted anywhere at any time using hybrid physically and empirically based models. Here, we test these methods across a sparsely vegetated and topographically diverse sub‐Antarctic island ecosystem (Macquarie Island). Innovation: Microclimate predictions were generated at a height of 4 cm above the surface on a 100 × 100 m elevation grid across the island for the snow‐free season (Oct–Mar), with models driven by either climate reanalysis data (CRA) or CRA data augmented with meteorological observations from the island's automatic weather station (AWS+CRA). These models were compared with predictions from a simple lapse rate model (LR), where an elevational adjustment was applied to hourly temperature measurements from the AWS. Prediction errors tended to be lower for AWS+CRA‐driven models, particularly when compared to the CRA‐driven models. The AWS+CRA and LR models had similar prediction errors averaged across the season for Tmin and Tmean, but prediction errors for Tmax were much smaller for the former. The within‐site correlation between observed and predicted daily Tmean was on average >0.8 in all months for AWS+CRA predictions and >0.7 in all months for LR predictions, but consistently lower for CRA predictions. Main conclusions: Prediction of microclimate conditions at ecologically relevant spatial and temporal scales is now possible using hybrid models, and these often provide added value over lapse rate models, particularly for daily extremes and when driven by in situ meteorological observations. These advances will help add the microclimate dimension to ecological and biogeographic studies and aid delivery of climate change‐resilient conservation planning in climate change‐exposed ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: In regions where snowfall historically has been a defining seasonal characteristic of the landscape, warming winters have reduced the depth, duration, and extent of snowpack. However, most management and conservation has focused on how aboveground wildlife will be affected by altered snow conditions, even though the majority of species that persist through the winter do so under the snowpack in a thermally stable refugium: the subnivium. Shortened winters, forest management practices, and winter recreation can alter subnivium conditions by increasing snow compaction and compromising thermal stability at the soil–snow interface. To help slow the loss of the subnivium in the face of rapidly changing winter conditions, we suggest managers adopt regional conservation plans for identifying threatened snow‐covered environments; measure and predict the effects land cover and habitat management has on local subnivium conditions; and control the timing and distribution of activities that disturb and compact snow cover (e.g., silvicultural practices, snow recreation, and road and trail maintenance). As a case study, we developed a spatially explicit model of subnivium presence in a working landscape of the Chequamegon National Forest, Wisconsin. We identified landscapes where winter recreation and management practices could threaten potentially important areas for subnivium persistence. Similar modeling approaches could inform management decisions related to subnivium conservation. Current climate projections predict that snow seasons will change rapidly in many regions, and as result, we advocate for the immediate recognition, conservation, and management of the subnivium and its dependent species. [ABSTRACT FROM AUTHOR]

Land-cover and climate change are both expected to alter species distributions and contribute to future biodiversity loss. However, the combined effects of land-cover and climate change on assemblages, especially at the landscape scale, remain understudied. Lowland tropical amphibians may be particularly susceptible to changes in land cover and climate warming because many species have narrow thermal safety margins resulting from air and body temperatures that are close to their critical thermal maxima (CTmax). We examined how changing thermal landscapes may alter the area of thermally suitable habitat (TSH) for tropical amphibians. We measured microclimates in 6 land-cover types and CTmax of 16 frog species in lowland northeastern Costa Rica. We used a biophysical model to estimate core body temperatures of frogs exposed to habitat-specific microclimates while accounting for evaporative cooling and behavior. Thermally suitable habitat area was estimated as the portion of the landscape where species CTmax exceeded their habitat-specific maximum body temperatures. We projected changes in TSH area 80 years into the future as a function of land-cover change only, climate change only, and combinations of land-cover and climate-change scenarios representing low and moderate rates of change. Projected decreases in TSH area ranged from 16% under low emissions and reduced forest loss to 30% under moderate emissions and business-as-usual land-cover change. Under a moderate emissions scenario (A1B), climate change alone contributed to 1.7- to 4.5-fold greater losses in TSH area than land-cover change only, suggesting that future decreases in TSH from climate change may outpace structural habitat loss. Forest-restricted species had lower mean CTmax than species that occurred in altered habitats, indicating that thermal tolerances will likely shape assemblages in changing thermal landscapes. In the face of ongoing land-cover and climate change, it will be critical to consider changing thermal landscapes in strategies to conserve ectotherm species. [ABSTRACT FROM AUTHOR]

1. Survival of overwintering monarch butterflies following severe wet winter storms in Mexico is substantially higher for butterflies that form clusters on the oyamel fir tree trunks than for those that form clusters on the fir boughs. 2. Thermal measurements taken at similar elevations with a weather station on the Sierra Chincua and within a Cerro Pelon and a Sierra Chincua overwintering area indicated that clustering on the fir trunks provides dual microclimatic benefits for the butterflies. a. At night, the minimum surface temperatures of all firs combined averaged 1.4 °C warmer than ambient forest temperatures, thereby enhancing protection against freezing for monarchs that are either wet or dry. We term this the ‘hot water bottle effect.’ b. During the day, the maximum surface temperatures of all firs combined averaged 1.2 °C cooler than ambient, a difference sufficient to lower the loss of the butterflies’ lipid stores over the 154-day wintering season. 3. Larger diameter trees increase both microclimate benefits. 4. The results add a new dimension to improving the conservation management guidelines for the Monarch Butterfly Biosphere Reserve. Strict enforcement against culling of larger trees and in favour of promoting old-growth oyamel forests will enhance two microclimatic benefits: butterfly mortality during severe winter weather will be reduced, and the butterflies’ lipid savings over the winter will be enhanced. [ABSTRACT FROM AUTHOR]