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Understanding the drivers affecting species richness and composition in local communities is crucial for discerning differences among communities in a specific region. In large regions, a variety of environmental conditions shape diversity, reflecting the peculiarities of each location, such as available resources and species interactions. While many species are associated with forest habitats, some can adapt to open environments, reflecting how environmental changes affect ant assemblages. The southwestern Brazilian Amazon stands out for significant contrasts in precipitation and forest cover, with the drier and deforested east compared to the wetter and forested west. Thus, we investigated how precipitation, forest cover and spatial distance influence ant species richness and composition. We conducted the study by selecting 16 sampling areas. We collected 365 species, of which 151 were classified based on their habitat use. We observed that increased forest cover is directly related to increased ant species richness, especially for forest specialists, highlighting the sensitivity of these species to forest habitat loss or gain. Additionally, we found that spatial distance between communities plays a significant role in explaining variance in ant species composition, surpassing the influence of forest cover. However, species composition is still influenced by variability in forest cover and precipitation, even when controlling for geographical distance. Our results provide important insights into ant diversity and composition in the Amazon. We emphasize the importance of considering the different responses of ants to environmental factors, using habitat‐use guilds, to guide effective biodiversity conservation measures.

Studies of habitat selection and use by wildlife, especially large herbivores, are foundational for understanding their ecology and management, especially if predictors of use represent habitat requirements that can be related to demography or fitness. Many ungulate species serve societal needs as game animals or subsistence foods, and also can affect native vegetation and agricultural crops because of their large body size, diet choices, and widespread distributions. Understanding nutritional resources and habitat use of large herbivores like elk (Cervus canadensis) can benefit their management across different land ownerships and management regimes. Distributions of elk in much of the western United States have shifted from public to private lands, leading to reduced hunting and viewing opportunities on the former and increased crop damage and other undesired effects on the latter. These shifts may be caused by increasing human disturbance (e.g., roads and traffic) and declines of early-seral vegetation, which provides abundant forage for elk and other wildlife on public lands. Managers can benefit from tools that predict how nutritional resources, other environmental characteristics, elk productivity and performance, and elk distributions respond to management actions. We present a large-scale effort to develop regional elk nutrition and habitat-use models for summer ranges spanning 11 million ha in western Oregon and Washington, USA (hereafter Westside). We chose summer because nutritional limitations on elk condition (e.g., body fat levels) and reproduction in this season are evident across much of the western United States. Our overarching hypothesis was that elk habitat use during summer is driven by a suite of interacting covariates related to energy balance: acquisition (e.g., nutritional resources, juxtaposition of cover and foraging areas), and loss (e.g., proximity to open roads, topography). We predicted that female elk consistently select areas of higher summer nutrition, resulting in better animal performance in more nutritionally rich landscapes. We also predicted that factors of human disturbance, vegetation, and topography would affect elk use of landscapes and available nutrition during summer, and specifically predicted that elk would avoid open roads and areas far from cover-forage edges because of their preference for foraging sites with secure patches of cover nearby. Our work had 2 primary objectives: 1) to develop and evaluate a nutrition model that estimates regional nutritional conditions for elk on summer ranges, using predictors that reflect elk nutritional ecology; and 2) to develop a summer habitat-use model that integrates the nutrition model predictions with other covariates to estimate relative probability of use by elk, accounting for ecological processes that drive use. To meet our objectives, we used 25 previously collected data sets on elk nutrition, performance, and distributions from 12 study areas. We demonstrated the management utility of our regional-scale models via application in 2 landscapes in Washington. The elk nutrition model predicts levels of digestible energy in elk diets (DDE; kcal DE/g of consumed forage) during summer. Model input data were from foraging experiments using captive female elk and field measurements of site characteristics at fine scales (∼0.5 ha). The nutrition model included a set of equations that predicted forage biomass as a function of site characteristics and a second set that predicted DDE primarily as a function of forage biomass. We used the nutrition model to develop a DDE map across the Westside. We then evaluated performance of the model by comparing predicted DDE to nutritional resource selection by elk and to population-level estimates of autumn body fat and pregnancy rates of lactating elk. To model elk habitat use, we compiled 13 unique telemetry data sets from female elk (n = 173) in 7 study areas (data collected June–August 1991–2009). We used a generalized linear model with 5 of the data sets, coupled with ecologically relevant covariates characterizing nutrition, human disturbance, vegetation, and physical conditions, to estimate intensity of use with the negative binomial model. We evaluated model performance by mapping predicted habitat use with the regional model and comparing predictions with counts of elk locations using 8 independent telemetry data sets. The nutrition model explained a reasonably high amount of variation in forage biomass (r² = 0.46–0.72) and included covariates of overstory canopy cover, proportion of hardwoods in the canopy, potential natural vegetation (PNV) zone, and study area. Dietary DE equations in the model explained about 50% of the variation in DDE (r² = 0.39–0.57) as a function of forage biomass by PNV zone and study area. Broad-scale application of the nutrition model in the Westside region illustrated the predominance of landscapes that failed to meet nutritional needs of lactating females (≤2.58 kcal/g) and their calves, especially at moderate elevations in closed-canopy forests in both the Coast Range and the southern Cascades. Areas providing DDE at (>2.58–2.75 kcal/g) or in excess (>2.75 kcal/g) of the basic requirement of lactating females were uncommon (<15% of area) or rare (<5% of area), respectively, and primarily occurred in early-seral communities, particularly at higher elevations. Wild elk avoided areas with DDE below basic requirement and selected for areas with DDE >2.60 kcal/g. Percentage of elk ranges providing DDE levels near or above basic requirement was highly correlated with pregnancy rates of lactating females. Autumn body fat levels were highly correlated with percentage of elk ranges providing DDE levels above basic requirement. The regional model of elk habitat use with greatest support in the empirical data included 4 covariates: DDE, distance to nearest road open to motorized use by the public, distance to cover-forage edge, and slope. Elk preferred habitats that were relatively high in DDE, far from roads, close to cover-forage edges, and on gentle slopes. Based on standardized coefficients, changes in slope (−0.949) were most important in predicting habitat use, followed by DDE (0.656), distance to edge (−0.305), and distance to open road (0.300). Use ratios for the regional model indicated these changes in relative probability of use by elk: a 111.2% increase in use for each 0.1-unit increase in DDE; a 22.7% increase in use for each kilometer away from an open road; an 8.1% decrease in use for each 100-m increase in distance to edge; and a 5.3% decrease in use for each percent increase in slope. The regional model validated well overall, with high correlation between predicted use and observed values for the 4 Washington sites (rs ≥ 0.96) but lower correlation in southwestern Oregon sites (rs = 0.32–0.87). Our results demonstrated that nutrition data collected at fine scales with captive elk can be used to predict nutritional resources at large scales, and that these predictions directly relate to habitat use and performance of free-ranging elk across the Westside region. These results also highlight the importance of including summer nutrition in habitat evaluation and landscape planning for Westside elk. The models can inform management strategies to achieve objectives for elk across land ownerships. The regional model provides a useful tool to understand and document spatially explicit habitat requirements and distributions of elk in current or future landscapes. The 2 examples of management application demonstrated how effects of management on elk nutrition and habitat use can be evaluated at landscape scales, and in turn how animal performance and distribution are affected. Results further illustrated the importance of managing for nutrition in combination with other covariates (i.e., roads, slope, cover-forage edges) that affect elk use of nutritional resources to achieve desired distributions of elk. Our meta-analysis approach to habitat modeling provides a useful framework for research and management of wildlife species with coarse-scale habitat requirements by identifying commonalities in habitat-use patterns that are robust across multiple modeling areas and a large geographic range. Use of such methods in future modeling, including application in monitoring programs and adaptive management, will continue to advance ecological knowledge and management of wildlife species like elk. © 2018 The Authors. Wildlife Monographs published by Wiley on behalf of The Wildlife Society. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. Los estudios de selección y uso de hábitats por la vida silvestre, especialmente herbívoros grandes, son fundamentales para comprender su ecología y gestión, especialmente si los predictores de uso representan requisitos de hábitat que pueden estar relacionados con la demografía o aptitud física. Muchas especies de ungulados sirven a las necesidades de la sociedad como animales de caza o alimento sustancial, y también pueden afectar la vegetación nativa y los cultivos agrícolas debido a sus grande opciones de dieta de tamaño corporal y su amplia distribución. El entendimiento de los recursos nutricionales y el uso de hábitat de grandes herbívoros como el alce (Cervus canadensis) puede beneficiar su gestión en diferentes propiedades de la tierra y regímenes de gestión. Distribuciones de alce en gran parte del oeste de los Estados Unidos han cambiado de tierras públicas a privadas, conduciendo a oportunidades a la caza y observación reducidas en la primera y el aumento del daño a los cultivos y otros efectos no deseados en este último. Estos cambios pueden ser causados por el aumento de la perturbac

Many aquatic species of conservation concern exist at low densities and are inherently difficult to detect or monitor using conventional methods. However, the introduction of environmental (e)DNA has recently transformed our ability to detect these species and enables effective deployment of limited conservation resources. Identifying areas for breeding, as well as the ecological distribution of species, is vital to the survival or recovery of a conservation species (i.e., areas of critical habitat). In many species, spawning events are associated with a higher relative abundance of DNA released within an aquatic system (i.e., gametes, skin cells etc.), making this the ideal time to monitor these species using eDNA techniques. This study aims to examine whether a “snapshot” eDNA sampling approach (i.e., samples taken at fixed points in chronological time) could reveal areas of critical habitat including spawning sites for our target species Petromyzon marinus. We utilized a species‐specific qPCR assay to monitor spatial and temporal patterns in eDNA concentration within two river catchments in Ireland over three consecutive years. We found that eDNA concentration increased at the onset of observed spawning activity and patterns of concentration increased from downstream to upstream over time, suggesting dispersal into the higher reaches as the spawning season progressed. We found P. marinus to be present upstream of several potential barriers to migration, sometimes in significant numbers. Our results also show that the addition of a lamprey‐specific fish pass at an “impassable” weir, although assisting in ascent, did not have any significant impact on eDNA concentration upstream after the pass had been installed. eDNA concentration was also found to be significantly correlated with both the number of fish and the number of nests encountered. The application of snapshot sampling techniques for species monitoring therefore has substantial potential for the management of low‐density species in fast‐moving aquatic systems. Many aquatic species of conservation concern exist at low densities and are inherently difficult to detect or monitor using conventional methods. Here, we used a “snapshot” eDNA sampling approach to reveal relative patterns in eDNA concentration within a river catchment. Using this approach, we successfully outlined fine‐scale spatio‐temporal patterns of movement as well as uncovering the location of critical habitat and spawning sites for our target species Petromyzon marinus.

The critically endangered Siberian crane (Leucogeranus leucogeranus) is the world’s third most endangered species of crane. Despite the enhanced conservation actions in recent years, there are pieces of evidence that suggest that its population is continuously decreasing. To gain insights into the possible causes of the population decline, we tracked nine Siberian cranes in Russia and Mongolia using GPS transmitters. We obtained migration episodes based on over 0.31 million subsequent locations from 3283 bird days between June 1995 and December 2021. Siberian cranes migrated an average of 5604 ± 362 km in spring from wintering to breeding areas and a mean of 5265 ± 454 km from breeding to wintering areas. We identified 35 staging sites along the migration corridor, including 17 critical staging sites at which birds staged for >14 days and 18 stopover sites that supported individuals for more than two days within a ca. 200 km-wide migratory corridor. Of the areas used by the tagged cranes, 77% of the breeding areas in Russia, 55% of the staging areas, 99% of the non-breeding summering area in Mongolia, and 50% of the wintering areas in Poyang Lake in China lay outside the current protected area network. Although we should be prudent about interpreting the conservation gaps of the entire population from only a few tracked birds, these results strongly suggest that the current protection network for this numerically rare species is inadequate, requiring urgent review.

How intensely animals use habitat features depends on their functional properties (i.e., how the feature influences fitness) and the spatial and temporal scale considered. For herbivores, habitat use is expected to reflect the competing risks of starvation, predation, and thermal stress, but the relative influence of each functional property is expected to vary in space and time. We examined how a dietary and habitat specialist, the pygmy rabbit (Brachylagus idahoensis), used these functional properties of its sagebrush habitat—food quality, security, and thermal refuge—at two hierarchical spatial scales (microsite and patch) across two seasons (winter and summer). At the microsite and patch scales, we determined which plant functional traits predicted the number of bites (i.e., foraging) by pygmy rabbits and the number of their fecal pellets (i.e., general habitat use). Pygmy rabbits used microsites and patches more intensely that had higher crude protein and aerial concealment cover and were closer to burrows. Food quality was more influential when rabbits used microsites within patches. Security was more influential in winter than summer, and more at Cedar Gulch than Camas. However, the influence of functional properties depended on phytochemical and structural properties of sagebrush and was not spatiotemporally consistent. These results show function‐dependent habitat use that varied according to specific activities by a central‐place browsing herbivore. Making spatially explicit predictions of the relative value of habitat features that influence different types of habitat use (i.e., foraging, hiding, and thermoregulating) will improve how we predict patterns of habitat use by herbivores and how we monitor and manage functional traits within habitats for wildlife. We examined how a dietary and habitat specialist, the pygmy rabbit (Brachylagus idahoensis), responded to functional properties of its habitat—food quality, security, and thermal refuge—at two hierarchical spatial scales (microsite and patch) across two seasons (winter and summer) at two study sites. In general, pygmy rabbits used microsites and patches with higher crude protein and aerial concealment cover closer to burrows. These results show function‐dependent habitat selection that varies according to specific functional uses by a central‐place browsing herbivore.

The study of animal–habitat interactions is of primary importance for the formulation of conservation recommendations. Flying, gliding, and climbing animals have the ability to exploit their habitat in a three‐dimensional way, and the vertical canopy structure in forests plays an essential role for habitat suitability. Forest bats as flying mammals may seasonally shift their microhabitat use due to differing energy demands or changing prey availability, but the patterns are not well understood. We investigated three‐dimensional and seasonal habitat use by insectivorous bats in a temperate lowland old‐growth forest, the Belovezhskaya Pushcha in Belarus. We acoustically sampled broadleaved and mixed coniferous plots in the forest interior and in gaps in three heights during two reproductive periods (pregnancy/lactation vs. postlactation). In canopy gaps, vertical stratification in bat activity was less pronounced than in the forest interior. Vertical activity patterns differed among species. The upper canopy levels were important foraging habitats for the open‐space forager guild and for some edge‐space foragers like the Barbastelle bat Barbastella barbastellus and the soprano pipistrelle Pipistrellus pygmaeus. Myotis species had highest activity levels near the ground in forest gaps. Moreover, we found species‐dependent seasonal microhabitat shifts. Generally, all species and species groups considered except Myotis species showed higher activity levels during postlactation. Myotis species tended toward higher activity in the forest interior during postlactation. P. pygmaeus switched from high activity levels in the upper canopy during pregnancy and lactation to high activity levels near the ground during postlactation. We conclude that a full comprehension of forest bat habitat use is only possible when height in canopy and seasonal patterns are considered. We investigated three‐dimensional and seasonal habitat use by insectivorous bats in a temperate lowland old‐growth forest. We identified guild‐ and species‐specific differences in canopy height use and species‐dependent seasonal microhabitat shifts that can be explained by ecomorphological adaptations.

This work describes aspects of the ecology and feeding of Leporinus striatus to fill the gap in information about the species in Brazilian rivers. The study area is in the Ipanema National Forest, Iperó/São Paulo, with the Ipanema River as the place where the specimens were collected in its middle and lower reaches. The size ranged from class 9.0 - 9.5 cm to class 11.5 - 12.0 cm, with females being found in all classes. Class 10 - 10.5 was the one with the highest relative frequency, with males being most abundant in the 9.5-10.0 cm length class and females in the 10-10.5 cm length class. The species' diet was composed of autochthonous species, with the most frequent items being insect fragments and plant material. Based on this information, the species was classified as omnivorous. Underwater observations made it possible to verify that the species is gregarious, inhabiting the water column between midwater and the bottom, preferring stretches with currents and rocky substrate. It performs foraging by leaning its body close to the substrate and biting food on solid surfaces. Small groups made up of at least six individuals shared the areas between rocks and branches. We conclude that, to guarantee the preservation of the species, it is crucial to recognize the significant role played by Conservation Units. However, given the aquatic nature of the species studied, its life cycle is intrinsically linked to stretches that extend beyond the limits of the UC. Additionally, the ecological analyses presented in this study reveal that the species relies on the preservation of a healthy river environment that transcends the boundaries of the conversational unit.

Endangered leatherback sea turtles (Dermochelys coriacea) are wide‐ranging, long‐distance migrants whose movements are often associated with environmental cues. We examined the spatial distribution and habitat use for 33 satellite‐tracked leatherbacks from nesting beaches on the Caribbean coast of Costa Rica and Panama from 2004 to 2018, an important nesting population for the leatherback Northwest Atlantic Distinct Population Segment. Tracking revealed the use of two distinct regions, the Gulf of Mexico (GoM, n = 18) and the North Atlantic Ocean (NAO, n = 15). We developed density utilization maps to elucidate high‐use habitats, migration pathways, and seasonal movements. GoM leatherbacks were found in three concentrated high‐use habitats connected by a migration pathway, while NAO leatherbacks were primarily found in a single, large high‐use habitat. Leatherbacks in both regions have the potential to interact with Atlantic pelagic longline fisheries based on seasonal overlap with high fishing effort. Our findings suggest that the GoM is an important destination for leatherbacks from the Caribbean coast of Central America with seasonal movements between high‐use habitats within the GoM. While leatherbacks are utilizing high‐use habitats in both the NAO and the GoM, the proportion of individuals migrating into the GoM increased over the study period. Additionally, NAO leatherbacks have increased the distance they travel in the first 90 d. Regional differences in movement and spatial distribution of high‐use habitats are important considerations when developing conservation plans for the Northwest Atlantic leatherback population.

Habitat quality can have important consequences for avian communities through impacts on survival and annual reproductive success. However, habitat quality is often hard to measure, leading to the use of occupancy as a proxy. We compared habitat use of 5 avian species that used nest boxes in the oak woodlands of central coastal California, USA, to determine which habitat characteristics best predicted box occupancy. We focused on the relationship between habitat characteristics and occupancy for five species—Ash-throated Flycatcher (Myiarchus cinerascens), House Wren (Troglodytes aedon), Oak Titmouse (Baeolophus inornatus), Violet-green Swallow (Tachycineta thalassina), and Western Bluebird (Sialia mexicana)—for which we had 12 consecutive years of data on nest boxes spread over a 700 ha study area. We also examined whether the physical habitat characteristics and box occupancy rates were good predictors of reproductive success, to infer whether they were useful indicators of habitat quality. The habitat characteristics influencing nest-box occupancy differed among the 5 species. Ash-throated Flycatchers were associated with fragmented habitats with less grassland. House Wrens were associated with riparian vegetation, as were Oak Titmice, which were also associated with chaparral. Violet-green Swallows were associated with chaparral but tended to nest farther from riparian corridors than Oak Titmice. Western Bluebirds nested away from riparian corridors and in areas with more grassland and oak woodland. Finally, occupancy rate was a better predictor than habitat characteristics of reproductive success, which suggests that occupancy can be a valuable proxy for habitat quality for these 5 species.

Hellbenders (Cryptobranchus alleganiensis) are long-lived, fully aquatic salamanders that inhabit cool, well-oxygenated streams and rivers in the eastern United States. Although once abundant, C. alleganiensis populations have experienced major declines across the historical range. Habitat degradation, siltation, aquatic contaminants, and infectious diseases are commonly suggested as contributors to these declines. Although Tennessee provides areas of high-quality habitat for C. alleganiensis, microhabitat differences among life stages are not well documented. We evaluated microhabitat use of larval, subadult, and adult C. alleganiensis at three streams in east Tennessee by comparing sites occupied by C. alleganiensis to random sites within each stream. We used multivariate analysis to evaluate microhabitat use differences among larval, subadult, and adult C. alleganiensis. We completed habitat assessments for 60 individuals. We detected an association between C. alleganiensis presence (regardless of life stage) and the percentage of large rock, the percentage of low embedded rocks, and the number of rocks above 500 mm. Furthermore, the volume of cover rock, the number of rocks above 500 mm, the distance to bank, and the percentage of low embedded rocks, gravel, and sand were the most important microhabitat attributes to discriminate life-stage distributions. Overall, our analyses identify microhabitat attributes that are potentially important for long-term C. alleganiensis conservation and provide guidance for stream protection and restoration practices that might mitigate sedimentation and habitat degradation in impacted streams.