查看更多>>摘要：? 2022 Elsevier LtdThe loss of larger frugivores alters seed dispersal. Species reintroductions have been proposed as a strategy for reversing local disperser extinctions. However, their effects on ecological processes have seldom been assessed. Howler monkeys (Alouatta guariba) have been reintroduced in Tijuca National Park, a defaunated Atlantic Forest fragment. We compared the fate of seeds dispersed by howlers to dispersal by two other frugivores present in the park: capuchin monkeys (Sapajus nigritus) and guans (Penelope superciliaris). Howlers produce clumped defecations that attract dung beetles, which provide secondary dispersal by burying seeds embedded in feces. We expected that seeds dispersed by howlers would have a different fate from those dispersed by capuchins and guans, since their scattered defecations are less attractive to dung beetles. We followed the fate of seeds 3–14 mm in diameter through three processes after seed deposition: secondary dispersal, predation, and seedling emergence. We estimated the probabilities in each step according to the primary disperser and plant species. Dispersal by howlers increased the recruitment of large-seeded plants because of the higher probability of secondary dispersal of the seeds in their feces. Fewer of the seeds dispersed by capuchins or guans were buried, regardless of size, and burial depths were shallower. For 3 mm seeds, the final recruitment probability was similar across frugivores. However, more of the larger seeds reached the seedling stage when dispersed by howlers since they were buried more deeply, which increased their survival without affecting seedling emergence. Reintroductions can thus contribute to restoring ecological processes.
查看更多>>摘要：? 2022Global abundances of oceanic pelagic sharks have declined due to overfishing. Internationally protected shark species remain at risk due to indiscriminate bycatch in longline fisheries with under-reported catches affecting reliability of population assessments for management. However, the scale of under-reporting remains poorly understood. Here we use detailed shark species catch data in a global fishing hotspot to show that the discards of three globally or regionally ‘Endangered’ or ‘Critically Endangered’ species (bigeye thresher Alopias superciliosus; oceanic whitetip Carcharhinus longimanus; smooth hammerhead Sphyrna zygaena) are potentially under-reported on a large scale: the total discards made by a single observed vessel in April–June 2018 in the eastern tropical Atlantic exceeded by 1.3–11.0 times the discards reported officially for these species Atlantic-wide for all of 2018. Scaling up observed catches (discards) of a single vessel to potential discards made by a single nation's fleet in the region, we estimate a mean annual total of 1526.2 t (±1 S.D. range: 415.3–2637.0 t), which exceeds by 89.2 times (±1 S.D. range: 24.3–154.2 times) the official reported discards for these three species. Without reducing bycatch mortality, which at present appears obscured by substantial under-reporting, Atlantic populations remain at serious risk.
查看更多>>摘要：? 2022 Elsevier LtdAncient forests are known to host a biodiversity of high ecological distinctiveness and are likely to provide habitat for red-listed species. Yet, few studies have investigated the role of forest continuity for the conservation of threatened species. We used species-presence data on red-listed species from 12 taxonomic groups (Spermatophyta, Pteridophyta, Bryophyta, Lichens, Chiroptera, Aves, Squamata, Amphibia, Coleoptera, Lepidoptera, Odonata and Orthoptera) to ascertain if ancient forests are an important habitat for threatened species in five mountain and subalpine protected areas in France. We compared the effect of the amount of historical forest (1853–1860) with the effect of the amount of current forest on the distribution of red-listed species in six circular landscape buffers ranging in radius from 100 to 1500 m. We showed that the amount of historical forest in the landscape had a positive effect on forest Spermatophyta, Bryophyta, Coleoptera and edge forest Pteridophyta with a better predictive power than current forest area, highlighting a colonization credit in recent forests. Conversely, edge-forest lepidopterans were more negatively affected by historical than by current forest area, highlighting an extinction debt in recent forests. Our findings underline that implementing protective measures of ancient forests would be a better strategy than afforestation to preserve threatened forest species in mountain and subalpine forest landscapes.
查看更多>>摘要：? 2022 Elsevier LtdIn the context of the global climate and biodiversity crises, forecasting the effectiveness of Protected Areas (PAs) and forest management to conserve biodiversity in the long-term is a high priority, especially in threatened environments. By combining distribution models and conservation planning protocols, we analyzed the effect of global climate and agriculture-linked activities in the long-term conservation opportunities of one most threatened deforestation hotspots: the South American Gran Chaco. We showed that assessing the effects of each driver of global change individually, promotes inaccurate long-term policies in deforestation hotspots. Our future scenarios indicated a low impact of climate change on the species distributions when it was analyzed individually. However, its effects were strongly exacerbated when both drivers of threat were combined in the same analyses, strongly diminishing conservation opportunities in the region: more than 50% of the remaining species' distribution and hotspot areas could be lost in the near future. In this dramatic context, we identified important opportunities to improve the level of long-term protection by increasing at least 5.6% the protection coverage and placing PAs strategically. It is imperative policymakers promote policies to generate a long-term improvement of conservation areas that are resilient to both threats as soon as possible for these threatened environments.
查看更多>>摘要：? 2022 Elsevier LtdProtected areas (including other effective area-based conservation measures) are a cornerstone of biodiversity conservation. Many countries are increasingly committed to expanding protected area coverage to 30%, which requires an increase in global annual spending from $24b to ~$140b (between $103b and $177b). We find that by trading nature-based carbon credits in voluntary carbon markets at the current average market price of $5 t?1CO2, 79 countries and territories can expand protected areas without capital deficit, together generate return on investments of $121b yr?1 and sequester 3 GtCO2eyr?1. Another 30 countries can meet at least half of their investment costs, and sequester an additional 2.8 GtCO2e yr?1. Additionally, we show that protection can extend to 33% of the Key Biodiversity Areas (KBAs) outside the existing protected area network. Our results point to the largely untapped potential of nature-based climate solutions to accelerate protected area expansion, thereby conserving biodiversity and mitigating climate change.
West T.A.P.Caviglia-Harris J.L.Martins F.S.R.V.Silva D.E....
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查看更多>>摘要：? 2022 The AuthorsProtected areas (PAs) are important policy instruments for forest conservation, but it is unclear if improved management can increase PA effectiveness. In Brazil, formal management plans are required to be in place shortly after the creation of a PA. This requirement is rarely enforced and, as a result, several PAs undergo many years without approved plans. We take advantage of this variation among PAs to study the impact of management plans on deforestation. We provide estimates from two quasi-experimental evaluation approaches based on the generalization of the difference-in-differences estimator: (1) matching-based methods for time-series cross-sectional data analysis and (2) the generalized synthetic control (GSC) method. We find weak, yet generally consistent, evidence across these two methods suggesting that PAs with approved management plans protect forests more effectively over time. Significant impact estimates from the matching-based approach ranged more widely than the GSC method (0.01%–0.09% versus 0.04%–0.05% of avoided deforestation per year, respectively). The effect size of these impacts is relatively substantial given that the average annual forest loss from our PA sample was 0.07% (±0.40%). To the extent that PAs with approved management plans reflect actual differences in PA management quality, our findings suggest that investments in improving PA management could result in positive conservation gains over time.
查看更多>>摘要：? 2022 Elsevier LtdLatin American countries have a high diversity of sharks, rays, and chimaeras, yet many species are at high risk of extinction due to numerous threats. The conservation of chondrichthyans is key to achieving healthy and productive aquatic ecosystems, and countries in Latin America are increasingly recognizing the need for aligning conservation strategies across jurisdictions with similar ecological and socioeconomic challenges. Reflecting on the current state of knowledge and providing consensus expert opinion on research priorities are critical steps to ensure sound management and conservation strategies for chondrichthyans. The present study is a multinational collaboration by leading researchers in Latin America to identify the top-ten research priorities for the conservation of chondrichthyans within this region. Our results were highlighted from a total of 20 broader relevant topics including taxonomy and biology, ecological function, climate change and other stressors, contribution to local economies, and international collaboration. This constitutes the first comprehensive academic perspective on research priorities for chondrichthyans in Latin America which considers the varied perceptions and perspectives related to the management of sharks, rays, and chimaeras across the region and beyond. The main conservation implications highlighted by our study relate to the urgent need to implement, evaluate and/or improve management regulations based on scientific evidence and interdisciplinary research, especially in areas with little progress on the subject and/or where species threatened by extinction are distributed.
查看更多>>摘要：? 2022 The AuthorsTo counteract ongoing biodiversity declines, many European countries have implemented agri-environment schemes (AES) such as ecological focus areas (EFAs), the efficiency of which is often questioned due to low levels of habitat quality. We established new grasslands (NG) using a more diverse seed mixture specifically adapted to mimic low-intensity meadows occurring in our study region in Lower Austria. We compared abundance, species richness, species assemblages and β diversity of solitary bees, bumblebees, syrphids, butterflies, orthopterans, true bugs and cicadas in currently subsidized legume-grass mixtures targeted at supporting pollinators (SG), old grasslands (OG) and NG over a two-year period. Bees, bumblebees and syrphids clearly profited from NG in terms of abundance and species richness, while SG were significantly less attractive. Butterflies were most abundant in OG and significantly less attracted to both SG and NG. True bugs were particularly attracted to NG and SG. However, we did not find any preference in cicadas. Orthopteran species richness was similar in all three types, but individual numbers were significantly lower in NG than in OG. OG and NG supported highly distinctive species assemblages. For solitary bees, syrphids, true bugs and cicadas distinctiveness of sites (β diversity) was more decisive for overall diversity than local diversity. We urge policy makers to put more effort into the establishment of EFAs by using high quality seed mixtures of regionally adapted species and increased plant diversity. Furthermore, preserving permanent grasslands, which support different sets of insect assemblages, should be focused as well to maximize biological conservation value.
查看更多>>摘要：? 2022 Elsevier LtdAlthough the bushmeat trade is a significant component of the Anthropocene crisis in the tropics, the reliability of species-level identification is generally lacking from bushmeat surveys. We conducted a comprehensive study of 23 bushmeat markets in Cameroon and one seizure from a French airport using a multi-gene DNA-typing approach and a dedicated species-assignment pipeline (DNABUSHMEAT). We identified 39 species-level taxa from 318 collected bushmeat items, including nine Cetartiodactyla, six Carnivora, three Pholidota, seven Rodentia, 12 Primates, one Squamata and one Crocodilia. DNA-typing allowed detecting three species previously unreported from the Cameroonian trade and clarifying the status of taxa subject to cryptic diversity (rodents) and shallow diagnostic characters (small carnivores, antelopes and guenons). Only 7% of the samples could not be assigned to the species-level, including two guenons and one snake, because of fluctuant taxonomy and weak representation in nucleotide databases. Almost half (43%) of the morphological identifications were corrected or refined by our DNA-typing approach. Generalized linear models showed that smoked specimens and primates were significantly suffering from inaccurate species identification. We also observed that customs (Paris) and market-recruited assistants (Cameroon) peaked at very high rates of inaccurate species identifications (87 and 100%, respectively), calling for cautiousness when third parties are involved in bushmeat surveys. Overall, >50% of the bushmeat species traded in Cameroon were nationally protected. Because accurate species identification is a central component of conservation strategies, we posit that our DNA-typing approach is a valuable asset for improving the traceability of the domestic and international bushmeat trade.
查看更多>>摘要：? 2022In Europe, the conservation of extensively grazed semi-natural grasslands is addressed by agricultural policies whose effectiveness is questioned. We studied sub-xerophilous Bromus erectus semi-natural grasslands to analyse the interactions among: i) agri-environmental payments, ii) grazing regimes, iii) environmental conditions, iv) habitat conservation state, and v) forage yield and quality. We sampled 98 plots across 19 farms and unmanaged control areas in five regions encompassing Italy and Switzerland. We fitted two piecewise structural equation models (SEM) to infer direct and indirect effects of agri-environmental payments, grazing regimes and environmental conditions on proxies of habitat conservation state, (i.e., the number and cover of diagnostic species), and forage yield and quality (i.e., specific leaf area - SLA, leaf dry-matter content - LDMC, sward height and pastoral value). Agri-environmental payments contributed to maintain grazing management and in turn to preserve the habitat biodiversity and functions. Payments did not affect stocking rates, but determined a more even distribution of grazing intensity, with positive effects on habitat conservation state and negative outcomes for LDMC. Conversely, LDMC increased with stocking rates. Among environmental condition, elevation and soil carbonates content had a positive effect on the habitat conservation state, while slope exerted only indirect effects on forage quality and diagnostic species by reducing fine-scale grazing intensity. Overall, the effectiveness of payments largely depended on the scale of measures' implementation. Farm-level grazing contracts and periodic field monitoring would allow to influence the fine-scale grazing intensity and to implement a result-oriented approach towards the objectives of the post-2020 CAP.
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