Perspectives in Ecology and Conservation最新文献

Area-based strategies for conservation include defining species richness and rarity hotspots. However, excluding vulnerable species (e.g., with restricted distribution and categorized as threatened), in establishing such hotspots may limit their representativeness, so the convenience of asserting them has been widely debated. To inform conservation assessments for the New World leaf-nosed bats (Chiroptera: Phyllostomidae), we identified hotspots based simultaneously on species richness and rarity of 214 species. We projected species range maps on a 0.5° × 0.5° longitude-latitude grid, from which we built a presence-absence matrix with 6951 sites. Using range-diversity plots, we described richness-rarity hotspots (sites with high species richness and presence of rare species) and poorness-rarity hotspots (with low species richness and presence of rare species). We assess the representativeness of the hotspots within established protected areas using the World Database on Protected Areas. The richness-rarity hotspot was located in the Andean zone from Peru to Panama within which 46 species of phyllostomid bats are distributed and 37% of its surface is protected. While the poorness-rarity hotspot was located in the northern region of Mexico and the Caribbean with 50 phyllostomid bats species and 19% of its surface protected. We hope that our analysis represents a relevant tool for the conservation of phyllostomid bats, which provide several ecosystem services and are currently facing different threats derived from anthropogenic activities.

Given the need for consistent databases for conservation planning and management in protected areas, a challenge is to develop more accessible approaches, while ensuring that the data are robust and fit for purpose. We compared the assemblage of medium and large vertebrates using three techniques, camera trap, diurnal line-transect census (sightings/vocalisations) and track and sign surveys, the latter two being carried out with the participation of local experts (local hunters). We observed that the methods employed were selective in detecting groups of species and, therefore, their use in combination is recommended for a more comprehensive assessment of wildlife biodiversity, as well as for detecting population trends. When evaluating the sightings/vocalisations and tracks and signs data together (given they can be applied concomitantly) in comparison to the camera traps, we verified that broadly the same numbers of species were detected, recording 29 and 28 species, respectively. The sightings/vocalizations were more efficient for detecting primates; track and signs allowed detection of most nocturnal and cryptic or evasive species (e.g., Artiodactyla and Cingulata); camera traps are most effective for rare carnivores and rodents. Thus, in an ideal scenario, the three methods should be used to monitor these species, however, the use of more accessible surveys to be practiced by local experts are efficient for most large and medium-sized vertebrate species. Considering developing countries such as Brazil, involving local experts and their knowledge in a monitoring program becomes essential for the continuity of monitoring in the long term.

Recent bioacoustic studies have shown different responses of insectivorous bats to native habitat loss. We examined the activity and species/sonotypes composition of aerial insectivorous bats present in a human-modified karst landscape in Southeast Brazil, characterized by the presence of semideciduous forest, pastures and Eucalyptus globulus monocultures. Using ultrasonic detectors, we investigated activity and identified bat species and/or sonotypes in the three habitat types. We compared the activity (as a surrogate for abundance) and composition of species/sonotypes present and used Generalized Linear Models to investigated whether canopy density, understory density and food availability influence the response of bats in these habitat types. Our main results demonstrate that the variables general passes and species/sonotype richness did not differ significantly between forest and pasture, however, both variables in these two environments differed significantly from the values ​​found for eucalyptus. We conclude that, in the studied agropastoral landscape, pastures interspersed with forest areas can be used by aerial insectivorous bats during foraging. However, we also found evidence that eucalyptus monocultures, not yet mature and without an understory, have a negative impact on the species/sonotype richness and activity of Neotropical aerial insectivorous bats.

The literature other than scientific journals (non-journals) is a valuable, but scattered and rarely used, source of evidence of the effectiveness of interventions applied for protection from mammalian predators. This study describes how journals and non-journals differ in relation to study designs, types of interventions, predator species, countries, and publication bias. I collected 411 journal cases (226 publications) and 97 non-journal cases (64 publications) covering the period 1955–2020, five study designs, six interventions, 28 species and 50 countries. Non-journals were important for two predators (leopard Panthera pardus and snow leopard P. uncia) and four countries (Canada, India, Russia and Sri Lanka). These species and countries have been affected by human-predator conflicts and the use of non-journals should become a habitual practice to mitigate conflicts. Information on other species and countries, and all study designs and interventions, was provided mostly or only in peer-reviewed journals. This study helps make the use of non-journals easier for researchers and conservation practitioners by providing and explaining a list of relevant literature and online resources.

Forest cover changes are influenced by socioeconomic and biophysical dynamics. However, the relative importance of both social and biophysical factors to forest loss and gain remains in debate. Previous research has focused mainly in identifying determinants of deforestation, while less is known regarding forest regrowth, especially in tropical forests. Here we investigated the spatial pattern and determinants of forest cover changes within a landscape which is representative of the biophysical and socioeconomic conditions found in the Atlantic Forest, and also presents an exceptional conservation value within this global biodiversity hotspot. Events of deforestation and regrowth were identified by comparing land cover maps from aerial images taken in 1975 and 2010. We controlled the spatial autocorrelation among events and used a machine learning algorithm and a selection model approach to build linear models explaining forest loss and gain. Main determinants of both forest loss and gain were biophysical factors, although some of they may also reflect socioeconomic underlying processes. Distance from Strictly Protected Areas (SPAs) was the single socioeconomic determinant important to forest change, in loss events. Both deforestation and forest regrowth were strongly associated with forest edges. Deforestation occurred more intensively on concave or flat areas, low solar radiation conditions, near forests, and far from SPAs. Diversely, forest regrowth occurred mostly in high slopes, low elevation areas, high solar radiation and near to forest edges. Our findings reinforce the important role of topography and protected area on forest change, and highlight edge zones are “hotspots” of forest cover dynamics. .

Disturbances modify local abiotic properties, habitat structure and resource availability, shaping community assembly and ecological interactions. Open ecosystems have an evolutionary relationship with fire. We evaluated the effects of patch burnings on grassland ant communities and patterns of seed removal. We established 14 plots of 10 m² in pairs in a disturbance-suppressed grassland in South Brazil. A random plot of each pair was burned, and another plot was the control. We accessed ant communities with pitfall-traps and sweeping net, and seed removal with seed traps in all plots prior the experimental fires, and then on three occasions following fires. We recorded 57 ant species belonging to 29 genera. Ant species composition did not significantly vary between treatments neither did ant body size. We detected significantly positive fire effects on ant richness after 1 month and 12 months, mediated by the increase in plant species richness in burned plots. Mean seed removal rates were increased in burned plots after 1 month. We showed that prescribed patch burnings in fire-prone grasslands promoted ant richness, and their foraging activity. Our study may serve as a basis for conservation decisions, showing the importance of maintenance of disturbances in grasslands.

The biodiversity knowledge has several deficits. The wallacean shortfall—related to species distribution unknowledge—is one of the most studied shortfalls. It is important to identify gaps and biases in spatial biodiversity knowledge. However, to find out where the main biodiversity deficits are we need to know how the biodiversity spatial sampling changes according to spatial scale. Here we use an extensive dataset of Atlantic Forest primates to test spatial bias as a function of spatial scales and cell-size resolutions. Our findings indicate that the sampling coverage and spatial knowledge of Atlantic Forest primates are biased depending on spatial cell-size resolution and scale. We also show that from a broad-scale perspective (regional and global) primate spatial knowledge is spatially unbiased regardless of cell-size resolution considered. In contrast, in narrow-scale perspectives the knowledge may have or not spatial bias depending on the cell-size resolution. Our results suggest that sampling bias can be present or more pronounced in narrow-scale in a local perspective. Thus, the choice of scale and spatial resolution on ecological studies must consider the potential impacts of sampling bias accordingly to each scale and cell-size resolution.

The greatest challenge that we currently face is generating integrative conservation strategies to guarantee the preservation not only of species richness, but also of ecological functions and evolutionary history. We propose to assess these different dimensions to identify areas of high multidimensional diversity (AMC), and exemplify this approach with cricetid mice, in a region of Mexico with high diversity that is considered a priority for global conservation. We elaborate models of the potential geographic distribution of 49 species of mice to predict their communities; we then used those predictions to calculate the number of rare species, and taxonomic, functional, and phylogenetic diversity. Subsequently, we identify AMC and evaluate their ecological integrity and the level to which they are protected by government and indigenous communities. We found a high spatial incongruity between the different dimensions of biodiversity, which indicates that in situ diversification processes and dispersal limitation drive spatial heterogeneous patterns of diversity. The AMC overlapped very little with the governmental (6.4%) and indigenous communities (15.2%) conservation areas, the Payments for Environmental Services initiative is the most overlaps. Half of the AMC had an intermediate ecological integrity. Protected areas systems protect few sites with high multidimensional biodiversity values, and half of the priority areas we identified requires restoration programs. The proposed methodology is an integral way to evaluate current protected areas systems and will be useful to guide effective and efficient conservation priorities involving evolutional and ecological dimensions of the biodiversity.

The distribution of the jaguar has decreased by approximately 50% with its conservation highly dependent upon its persistence and mobility in anthropogenic landscapes. Consequently, understanding the effects of land use on jaguar populations and their connectivity is a necessary precursor for effective conservation of the species. We simultaneously estimated jaguar density and landscape connectivity in the ranching landscape of the Dry Chaco of western Paraguay, a deforestation hotspot, as a function of proportional forest area using spatial capture-recapture modeling. Using camera trap sampling at four sites along a deforestation gradient of 17%–51% area deforested, we estimated densities of 0.44–1.6 individuals/100 km², whereby densities and connectivity from the more deforested sites were significantly lower than those from the less deforested sites. Our results warrant concern for the long-term viability of jaguar in the Paraguayan Dry Chaco, highlighting the need for the effective implementation of existing national laws and management plans for the conservation of the jaguar and its habitat. Furthermore, we showed the importance of accounting for landscape heterogeneity typical of anthropogenic landscapes in the conservation of the jaguar, suggesting results from protected areas may be generating unrepresentative inferences for jaguars in general, while indicating the need to place a greater research emphasis on anthropogenic landscapes to meet range-wide conservation goals for the jaguar.

Urban areas are expanding continuously inducing changes in raptor communities. However, our knowledge about urbanization impacts on raptor communities at continental scales is scarce. Therefore, the aim of this study is to relate geographical (city location) and environmental characteristics of cities with raptor species richness, taxonomic composition and functional composition in urban green spaces (UGS) of Neotropical cities. Data about raptor species present in UGS was compiled through search of scientific articles and thesis in databases. Raptor species richness increased in the tropics and decreased with increasing altitude. Species richness also increased with the increasing minimum UGS size of studies. Species composition dissimilarity was influenced by altitude and the geographic location of cities, and was dominated by species turnover. Scavengers were more frequent in cities of the east coast of Brazil, whereas semi-open habitat species were more frequent in southern South American cities. Raptor body size was related positively with UGS size. The results obtained confirmed the pattern of increasing raptor species richness in the tropics. However, anthropogenic factors such as green area loss in urban areas may influence the macrogeographical patterns of raptor species richness. The species composition dissimilarity between cities is dominated by a pattern of species replacements, related to species distributions in the Neotropics. Species functional traits were affected by macrogeographical factors and also by green area size, suggesting that urbanization may alter ecosystem processes provided by raptors. In short, the conservation and planning of large UGS is fundamental to maintain raptor communities in the Neotropical cities.