Perspectives in Ecology and Conservation最新文献

Agroforestry systems, such as shade coffee plantations, favor the maintenance of woody vegetation, which promotes the presence of pollinators such as hummingbirds. Many shade coffee plantations in Mesoamerica have been abandoned due to the fall in coffee prices and undergone succession processes that increase vegetation complexity. Alternatively, they have been replaced by cattle pastures, which negatively affect hummingbird-plant interactions. Here, we describe the structure of hummingbird-plant interaction networks in three types of land use―late-successional forests, coffee plantations, and cattle pastures―that were derived from a cloud forest in southern Mexico. For one year (2019–2020), we collected bimonthly quantitative data on hummingbird-plant interactions for each type of land use. We found that the network of each land use had a heterogeneous structure, and most species had few linkages. The late forests and coffee plantations had more species, pairs of interactions, and modularity than the cattle pastures. The cattle pasture network had the greatest robustness due to the presence of generalist hummingbirds, which are important for network cohesion in a great disturbance scenario. Furthermore, hummingbird visits were influenced by plant traits, such as foliage height diversity. The study findings suggest that the conversion of natural habitats have implications for the conservation of plant-pollinator interactions and that generalist pollinator species are key to disturbance resiliency.

We identified the 30% most-important forest remnants for conservation in the Atlantic Forest domain in South America based on three bird diversity components: (1) overall species potential distribution, (2) potential distribution of threatened species, and (3) diversity of functional traits. We evaluated the extent of overlap among priority areas using the different approaches and analysed the efficiency of the current Protected Areas network at protecting biodiversity in current and potential future (2040 and 2080) climate scenarios. The overlap among the most important areas is low among the different bird diversity components in all climate scenarios, and few changes were found in priority areas between the current and future scenario. The proportion of species that reached the minimum amount of their distribution areas protected varied from zero to 4% depending on the climate scenario and the species conservation status (threatened or not). Priority areas based on the potential distribution of threatened species were less correlated to areas based on the overall species potential distribution than to functional traits in all climate scenarios, suggesting that there might be considerable differences between species composition and their functionalities. Our analyses point out the main regions where resources should be allocated to conservation of birds in a mega-biodiversity region.

The crescent urbanization across the globe has widespread ecological consequences, affecting species distribution, demography and behaviour. In this study we aimed to identify, quantify, map and predict the occurrences of medium- to large-bodied (≥1 kg) mammal carnivorans across urban and peri-urban landscapes throughout Brazil. We use a news-based search to compose a dataset of occurrences across the Brazilian cities. Additionally, we gather various socio-environmental and geophysical variables from these urban areas to identify the drivers of carnivore presence across urban environments. Employing Kernel interpolation, we generate heatmaps to highlight and pinpoint regions in Brazil with the highest concentration of carnivorans species on urban areas. We also employed a Generalized Additive Models (GAM) approach to assess the predictive power of social-environmental and geophysical variables on the occurrence of carnivorans in urban landscapes of Brazil. Our findings pinpoint to an increase of potential human-wildlife conflicts likely given that the urban expansion over natural habitats had a rampant increase in the last decades. Finally, we highlight that our results can serve as a basis to improve urban planning and offer important insights into the intricate interplay of social and geophysical variables that influence the occurrences of carnivorans within urban environments in Brazil.

Shark populations have declined worldwide, and conservation measures have been necessary for their recovery and maintenance in natural areas. Despite efforts to protect sharks in marine sanctuaries and managed areas, the apparent recovery of shark populations in Brazilian Marine Protected Areas has sparked controversy after two incidents involving shark bites. Shark culling has been proposed in one of the most iconic Marine National Parks, and scientific diving has been forbidden at a Marine Sanctuary where a long-term ecological program that lasted 10 years had to be halted. We herein argue for a science-based approach for shark management and conservation in Brazil, better connecting conservation goals with economic benefits.

Conservation strategies often assume uniform response to habitat loss and fragmentation among species. We investigated whether bird species' responses to habitat changes vary based on their distribution range and local environmental suitability. Additionally, we explored associations between sensitivity responses and species traits, like dispersal ability, habitat specialization, and distribution range size. Our study focused on the Brazilian Atlantic Forest, encompassing 179 landscape sites and 81 bird species. Using additive and interactive relationships and used principal component analysis to correlate species traits with sensitivity patterns. We found four distinct patterns of population sensitivity patterns: no effect of geographical range or environmental suitability (21% of the species), higher sensitivity at the geographical edges or low suitability (14%), lower sensitivity in core or better areas (11%) or both extremes responding similarly (11%), with species showing no response to landscape changes (43%). Biogeographic and landscape factors interactively influenced population abundance, resulting in antagonistic or synergistic effects. Population responses to habitat loss and fragmentation varied based on range position or environmental suitability but weren’t consistently explained by species traits. Given these nuanced results, conservationists must refrain from generalizing species sensitivity without accounting for distribution range position and environmental suitability. To ensure the long-term survival of biodiversity, conservation efforts should be tailored to each species' specific needs, taking into account their spatial position and the synergistic or antagonistic effects of environmental stressors. Such targeted conservation efforts will be crucial in mitigating the impacts of habitat loss and fragmentation on bird populations within the Brazilian Atlantic Forest.

Ceratophrys ornata is an iconic and regionally threatened amphibian of the temperate grasslands from Argentina, Brazil, and Uruguay. Conservation assessments suggested that habitat loss is the main threat to the species, although no studies have yet explored the link between grassland replacement and C. ornata decline. Using a robust database with ∼1000 records from herpetological collections, citizen science, and long-term monitoring, we modeled the species' ecological niche to produce a map of suitable areas, where we searched for C. ornata using active and passive techniques. After exhaustive efforts, we failed to obtain recent records from Brazil and Uruguay. We also conducted Generalized Linear Models to explore the relationship between land use/cover, landscape configuration, and current species occurrence. Overall, results showed that C. ornata occurrence is negatively associated with variables related to native grasslands fragmentation and replacement (i.e., Distance to the Nearest Patch, Forest Plantations), suggesting that habitat loss may have driven local extinctions and population declines of the species. Finally, we outline the regional and national conservation needs of C. ornata and recommend focusing on in-situ conservation strategies for the Argentinean populations to ensure the species' viability.

A key target for reducing biodiversity loss, outlined in the post-2020 Global Biodiversity Framework, is to protect 30% of the planet by 2030 (30×30) in protected areas (PAs) and ‘other effective area-based conservation measures’ (OECMs). There is concern that focusing on expanding PAs could exacerbate existing inequalities and that this may not be a cost-effective means to conserve biodiversity. There is already a lack of funding for existing PAs with many ineffectively managed. OECMs offer a potential solution to reach area-based protection targets in a more economically feasible and equitable way. The focus for 30×30 should be on improving the effectiveness of existing PAs and recognising existing areas that are providing conservation benefits as OECMs.

It is now clear that dry forest regeneration relies on a set of regeneration mechanisms such as seed rain, seed and seedling banks, and resprouts that operate simultaneously, but their relative contribution and drivers remain poorly understood. In this paper, we examined the role of seed rain, seed soil bank, seedling, sapling, and resprout assemblages in the regeneration of a Caatinga dry forest in northeast Brazil. We also examined how these regeneration mechanisms respond to chronic disturbances, rainfall, soil fertility, and light in 18 plots located in old-growth forest stands. A total of 5239 seeds from seed rain, 932 seeds in the soil seed bank, 158 seedlings, 85 saplings and 416 resprouts were recorded. Overall regeneration mechanisms provided low-density and impoverished assemblages when examined isolated. Soil seed bank and seed rain provided up to 423 and 35.5 seeds per m², respectively. Seedling and sapling assemblages were dominated by a small set of species (mostly Jatropha mutabilis, Pityrocapa moliliformis, and Trischidium molle), which were both frequent and accounted for most of the individuals. Resprouting was the most important mechanism, accounting for 63.1% of all individuals in the seedling, sapling, and resprout assemblages. Chronic disturbances were identified as key drivers, negatively affecting several community-level attributes of seed rain, soil seed bank, seedlings, and resprouts. Soil fertility and leaf area index (i.e., light availability) were negatively related to seedling and sapling abundances, respectively. Furthermore, the effect of environmental factors on regeneration was more pronounced in disturbed areas. Species composition of saplings and resprouts were associated with chronic disturbances and environmental factors. Our results suggest that, in human-modified landscapes, Caatinga forest regeneration relies primarily on resprouting, while other mechanisms play a minor role in plant species recruitment and maintenance along gradients of disturbances and environmental factors. Given the predicted increase in aridity associated with increased human disturbance, the Caatinga dry forest may experience shifts in forest structure and regeneration patterns. We refer to an absolute prevalence of vegetative propagation leading to a low-statured forest dominated by multi-stem individuals, with unknown effects on long-term forest dynamics and resilience, including community-level homogenization.

The increasing frequency and severity of wildfires is a matter of concern for biodiversity conservation around the world. Integrated fire management (IFM) can effectively prevent wildfires or reduce damage, decreasing the extent of burned areas and consequently carbon emission. However, funding sources for IFM are scarce. The carbon emission avoided by IFM in an indigenous land in the Brazilian Pantanal equals to 100 million dollars per year in carbon credits. This amount could be used to finance IFM in this area, as well as other conservation initiatives, such as forest restoration. A well-implemented program to pay for prevented carbon emission could substantially reduce the extent of burned areas and solve the problem of wildfires in the Pantanal.