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Summary: Subsistence hunting provides an important food source for rural populations in tropical forests but can lead to wildlife depletion. Management of wildlife resources depends on assessments of hunting sustainability. We assessed the sustainability of subsistence hunting in two Amazonian Extractive Reserves. We examined hunting data from a community-based monitoring programme conducted in 30 communities during 63 consecutive months to address temporal trends in hunting yields in terms of catch per unit of effort of all game species and the six most hunted species. We also assessed the prey profiles across different communities. Game species composition did not differ between monitored communities, and the most hunted species were Tayassu pecari, large cracids, Cuniculus paca, Mazama spp., Tapirus terrestris and Pecari tajacu. Catch per unit of effort was stable for all game species and each of the most hunted species, indicating that hunting was generally sustainable. These findings reflect the exceptionally low human population density and continuous forest cover of the study landscape, and long-term hunting sustainability and local protein acquisition will depend on maintaining these social and environmental settings. The results also show that large Sustainable Use Protected Areas can help foster sustainable game management and should thus be included in public policies. [ABSTRACT FROM AUTHOR]

Brazil safeguards a vast network of parks and reserves, termed conservation units. The creation of conservation units follows a rigorous legal protocol that grants them long-term stability under varying degrees of formal protection against land-use change. Degazettement, downsizing or downgrading any conservation unit requires a law to be passed. Recent shifts in Brazilian conservation policy have, however, favoured infrastructure projects and agricultural land conversion, even when these initiatives are in direct conflict with established conservation units. Several bills have been proposed by the National Congress, threatening 27 conservation units and bringing the long-term political stability and legal immunity of hitherto sacrosanct reserves into serious question. [ABSTRACT FROM PUBLISHER]

Copyright of Bird Conservation International is the property of Cambridge University Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Constructing community fruit–frugivore networks has proved challenging in tropical forests to date, particularly in lowland Amazonia, which hosts the most diverse spectrum of frugivorous vertebrates and morphological fruit types worldwide. We assessed data on fruit resource production, frugivore assemblages and corresponding fruit–frugivore networks in two contrasting forest types along the Rio Juruá of western Brazilian Amazonia: seasonally flooded várzea (VZ) and unflooded terra firme forest (TF). Over 2 y we conducted monthly surveys of fruit patches and medium- to large-bodied vertebrate frugivores within three 100-ha plots (two TF, one VZ), supplemented by fruit surveys along 67 5-km transects distributed across two contiguous forest reserves (41 TF, 26 VZ). Observations of trophic interactions were supplemented by semi-structured interviews with experienced hunters and fishermen from 16 local communities. The resultant binary networks contained low proportions of all potential interactions (TF: 25.7%, VZ: 19.4%) between 36 functional groups of frugivores and 152 plant genera and, while we report significant heterogeneity in fruit resource use among broad frugivore guilds within each forest type, recursive partitioning analysis failed to clearly match differences in fruit selection to fruit traits. The annual flood pulse in várzea forests had an overriding influence on the species turnover of both fruit resources and frugivores between the two forest types, with higher-order effects on network structure. [ABSTRACT FROM PUBLISHER]

Extractive reserves account for a significant proportion of the remaining intact forest within Brazilian Amazonia. Managers of extractive reserves need to understand the livelihood strategies adopted by rural Amazonians in order to implement projects that benefit the livelihoods of local residents whilst maintaining forest integrity. Whilst resident populations are often descended from immigrant rubber-tappers, dynamic economic and social conditions have led to a recent diversification of land-use practices. This two-year study in two large contiguous extractive reserves encompassing both unflooded (terra firme) and seasonally flooded (várzea) forest, shows the degree to which local livelihood strategies of different settlements are heterogeneous. Extractive offtake of forest products and fish catches and agricultural activities, together with income from sales, for 82 households in 10 communities were quantified in detail by means of weekly surveys. The survey data were combined with interviews to examine the demographic and wealth profile, and engagement in alternative activities, in 181 households across 27 communities. All households and communities were engaged in all three subsistence activity types, but there was large variation in engagement with income-generating activities. Households within a community showed considerable congruence in their income-generating activity profiles, but there was significant variation between communities. Yields from agriculture and fishing were more temporally stable than extraction of highly-seasonal forest products. Generalized linear mixed models showed that forest type was consistently important in explaining yields of both agrarian and extractive products. Communities with greater access to terra firme forest were inherently more agricultural, and strongly committed to manioc production. Communities with greater access to flooded forest, however, showed a greater dependence on fishing. Conservation should be more attuned to the diversity and dynamism of livelihood strategies in protected areas; in particular, reserve managers and policy makers should account for the effect of local variation in physical geography when designing sustainable development projects. [ABSTRACT FROM PUBLISHER]

The forests of western Amazonia support high site-level biological diversity, yet regional community heterogeneity is poorly understood. Using data from line transect surveys at 37 forest sites in south-eastern Peru, we assessed whether local primate assemblages are heterogeneous at the scale of a major watershed. We examined patterns of richness, abundance and community structure as a function of forest type, hunting pressure, land-management regime and geographic location. The primate assemblage composition and structure varied spatially across this relatively small region of Amazonia (≈ 85 000 km2), resulting from large-scale species patchiness rather than species turnover. Primate species richness varied among sites by a factor of two, community similarity by a factor of four and aggregate biomass by a factor of 45. Several environmental variables exhibited influence on community heterogeneity, though none as much as geographic location. Unflooded forest sites had higher species richness than floodplain forests, although neither numerical primate abundance nor aggregate biomass varied with forest type. Non-hunted sites safeguarded higher abundance and biomass, particularly of large-bodied species, than hunted sites. Spatial differences among species assemblages of a relatively generalist taxon like primates in this largely undisturbed forest region imply that community heterogeneity may be even greater in more species-rich taxa, as well as in regions of greater forest habitat diversity. [ABSTRACT FROM PUBLISHER]

The response of tropical fauna to landscape-level habitat change is poorly understood. Increased conversion of native primary forest to alternative land-uses, including secondary forest and exotic tree plantations, highlights the importance of assessing diversity patterns within these forest types. We sampled 1848 moths from 335 species of Arctiidae, Saturniidae and Sphingidae, over a total of 30 trap-nights. Sampling was conducted during the wet season 2005, using three light-traps at 15 sites within areas of primary forest, secondary forest and Eucalyptus urograndis plantations in northern Brazilian Amazonia. The Jari study region provides one of the best opportunities to investigate the ecological consequences of land-use change, and this study is one of the first to examine patterns of diversity for a neotropical moth assemblage in a human-dominated landscape in lowland Amazonia. We found that the three moth families responded consistently to disturbance in terms of abundance and community structure but variably in terms of species richness, in a manner apparently supporting a life-history hypothesis. Our results suggest that secondary forests and Eucalyptus plantations can support a substantial level of moth diversity but also show that these forest types hold assemblages with significantly distinct community structures and composition from primary forest. In addition, the ability of these converted land-uses to support primary forest species may be enhanced by proximity to surrounding primary forest, an issue which requires consideration when assessing the diversity and composition of mobile taxa in human-dominated landscapes. [ABSTRACT FROM PUBLISHER]

Little is known about the contribution of different forest types to the beta-diversity, abundance and biomass of the avifauna in lowland Amazonia. This paper presents data on the large-bodied bird assemblages of adjacent upland (terra firme) and seasonally flooded (várzea and igapó) forests in the lower Rio Purús region of central-western Brazilian Amazonia. We focus our analysis on 23 large-bodied canopy and terrestrial bird species from 10 families, on the basis of 2,044 bird sightings obtained during line-transect censuses conducted over a two-year period. Large toucans comprised the most numerically abundant large birds in terra firme and igapó forests, whereas macaws were the most abundant in nutrient-rich várzea forests that were seasonally inundated by white-water. The aggregate population density of all bird species in terra firme forest was slightly higher than that in várzea forest. Igapó forest, which was seasonally inundated by black-water, sustained the lowest population densities. Terra firme and várzea forests differed considerably in species composition and abundance whereas igapó forest shared many species with both terra firme and várzea. Our results suggest that Amazonian floodplain forests play a major role in the persistence and community dynamics of the large-bodied forest birds.Pouco se sabe sobre a contribuição de diferentes tipos de florestas aos padrões de beta-diversidade, abundância e biomassa da avifauna na região amazônica. Este artigo apresenta dados à respeito das aves de médio a grande porte em florestas de terra firme e florestas adjacentes sujeitas a inundação sazonal (várzea e igapó) na região do baixo Rio Purús da Amazonia centro-ocidental. Nossa análise, baseada num total de 2,044 observações obtidas durante censos ao longo de transectos, foi direcionada a 23 espécies de aves de médio a grande porte pertencentes a 10 famílias. As aves mais abundantes em florestas de terra firme e igapó foram os tucanos, e as araras as mais abundantes em florestas de várzea. A densidade de população agregada de todas as espécies na terra firme foi ligeiramente mais elevada do que na várzea. A floresta de igapó sustentaram as mais baixas densidades populacionais. Terra firme e várzea diferem consideravelmente na composição e abundância de espécies, visto que a avifauna do igapó é intermediária entre a da terra firme e a da várzea. Os resultados sugerem que as florestas inundáveis tem uma papel muito importante na manutenção das comunidades de aves de grande porte na Amazônia, e pricipalmente aquelas espécies que usam grandes mosaicos de floresta. [ABSTRACT FROM PUBLISHER]

The ‘arc of deforestation’ of southern Amazonia has one of the highest deforestation rates documented anywhere in the world. Landscape changes in a poorly studied but strategically important region in the Brazilian Amazon were studied using biennial Landsat TM/ETM+ images from 1984 to 2004. Deforestation rate for the period 1984–2004 was 2.47% yr−1 in the 7295 km2 study area, but decreased to 1.99% and 2.15% in 2000–2002 and 2002–2004, respectively. Landscape structure changes were characterized by smaller forest patches that were further apart, but increasingly complex in shape. Deforestation was mainly driven by cattle ranching, which in turn was affected by distance to roads, with forest cover increasing at greater distances from roads. A multi-layer perceptron was used to develop future scenarios based on Markov Chain analysis. Based on current land use, forest cover in the region will decline from 42% in 2004 to 21% by 2016. Results indicate a critical threshold at 51% of forest cover in which landscape structure and connectivity changes abruptly. This suggests that the region requires greater efforts in environmental law enforcement, land-use planning and education programmes to maintain the remaining forest cover near this threshold. [ABSTRACT FROM PUBLISHER]

Secondary forests account for 40% of all tropical forests yet little is known regarding their suitability as habitat for diurnal large mammals and game birds. This is especially so for second-growth that develops on large areas of degraded land. We address this by investigating assemblages of large-bodied birds and mammals in extensive patches of secondary forest in the Jarí region of the north-eastern Brazilian Amazon, comparing species richness and abundance against that of adjacent undisturbed primary forests. We conducted 184 km of line-transect censuses over a period of 3 mo, and found that although primary and secondary forests held a similar abundance of large vertebrates, the species composition was very different. Secondary forests supported a high abundance of ungulate browsers (0.85 vs 0.44 indiv. per 10 km) and smaller-bodied primates (15.6 vs 4.6 indiv. per 10 km) compared with primary forests. However, large prehensile-tailed primates were absent (black spider monkey Ateles paniscus) or at very low abundance (Guyanan red howler monkey Alouatta macconelli) in secondary forest. The abundance of large frugivorous/granivorous birds was also low in secondary forests compared with primary forests (22.6 vs 37.1 individuals per 10 km, respectively). Faunal assemblages appear to reflect food resource availability. Concurrent vegetation surveys indicated that secondary forests had high levels of terrestrial and understorey browse. Fruit production was largely restricted to pioneer trees such as Bellucia and Inga spp. Although these regenerating forests were an important habitat for large mammals and birds, they were limited in terms of faunal richness, particularly dispersers of large-seeded plants. [ABSTRACT FROM PUBLISHER]

Tree characteristics were recorded from 2829 standing trees in 24 0.25-ha terra firme forest plots in central Amazonia, 3 y after a surface fire had swept through the study area. Sixteen of the plots were within forest that burnt for the first time at the end of the 1997-98 El Niño (ENSO) event, and the remaining eight plots were within unburnt primary forest. In order to investigate the morphological correlates of tree mortality, we measured tree diameter at breast height (dbh) and bark thickness, and recorded burn height, bark roughness and the presence of latex, resin and buttress roots. Leaf litter depth was also recorded at the base of all trees in the unburnt forest. Using logistic regression models, tree mortality was best explained by the burn height, although dbh and the presence of buttresses were also important. Buttressed trees were associated with deeper leaf litter accumulation at their bases and higher char heights than trees without buttresses. Moreover, trees surviving the fire had significantly thicker bark than living trees in unburnt forest plots, indicating that thin-barked trees are more prone to selective mortality induced by heat stress. Latex did not appear to have had any significant effects on mortality, though resins were less abundant amongst the live trees in the burnt forest than in the unburnt controls. Levels of fire-mediated tree mortality in this study are compared with those in other Amazonian forest regions in light of historical factors affecting tree resistance to fires. [ABSTRACT FROM PUBLISHER]

Copyright of Journal of Tropical Ecology is the property of Cambridge University Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents data from a standardized series of line-transect censuses on the species and subspecies composition, population density, and crude biomass of western Amazonian primate communities occurring at eight flooded (= vázea) and 12 unflooded (= terra firme) forests. These were located primarily along one of the largest white-water tributaries of the Amazon (= Solimōes), the Juruá river. On average, terra firme forests contained twice as many primate species, lower population densities, and less than half of the total community biomass than did adjacent várzea forests. There was a clear habitat-dependent positive association among primate species, particularly within várzea forests, as well as marked shifts in guild structure between forest types. Species turnover between these two forest types involved primarily understorey insectivores (e.g. Saguinus sp.), which do not occur in seasonally inundated forest. These were consistently replaced by squirrel monkeys (Saimiri sp.), which are extremely abundant in annually flooded várzea forests. Similarly, large-bodied folivores such as red howler monkeys (Alouatta seniculus) were uncommon or rare in terra firme forests, but very abundant in várzea forests, even though they are hunted less intensively in the former than in the latter. This can be largely explained by the nutrient-rich alluvial soils of young floodplains, compared to the heavily weathered terra firme soils occurring even within short distances of major white-water rivers. This study clearly shows a reversed diversity/density pattern resulting from the lower species richness, but high overall community biomass of seasonally flooded Amazonian forests, which can now be generalized for a wide range of terrestrial vertebrate taxa, including amphibians, birds, and several other orders of mammals. [ABSTRACT FROM PUBLISHER]

The effects of escape distance to parental trees and tree clusters on the removal of Brazil-nut seeds (Bertholletia excelsa, Lecythidaceae) by vertebrate seed predators were examined in an entirely undisturbed stand of Brazil-nut trees of eastern Amazonia. Population density estimates, based on line-transect censuses, are also presented for Bertholletia trees and agoutis (Dasyprocta leporina), the most important scatterhoarder and seed predator of Brazil-nuts at this site. Seed removal experiments were conducted within and outside a natural Bertholletia tree cluster (castanhal) during both the wet and dry seasons. While there were no within-cluster effects of escape distance from parent trees on seed removal rates, overall seed removal within the cluster was significantly greater than that well outside the cluster. Moreover, removal rates in the wet season were consistently higher than those in the dry season both within and outside the tree cluster. Results suggest that the probability of early seed survival for Bertholletia, in relation to distance to seed sources, operates on different spatial scales, and that seed predators allocate greater foraging effort to scattered seeds during the fruitfall (wet) season, when buried seed stocks are being cached by agoutis. [ABSTRACT FROM PUBLISHER]

In many disturbed terrestrial landscapes, a subset of native generalist vertebrates thrives. The population trends of these disturbance-tolerant species may be driven by multiple factors, including habitat preferences, foraging opportunities (including crop raiding or human refuse), lower mortality when their predators are persecuted (the 'human shield' effect) and reduced competition due to declines of disturbance-sensitive species. A pronounced elevation in the abundance of disturbance-tolerant wildlife can drive numerous cascading impacts on food webs, biodiversity, vegetation structure and people in coupled human-natural systems. There is also concern for increased risk of zoonotic disease transfer to humans and domestic animals from wildlife species with high pathogen loads as their abundance and proximity to humans increases. Here we use field data from 58 landscapes to document a supra-regional phenomenon of the hyperabundance and community dominance of Southeast Asian wild pigs and macaques. These two groups were chosen as prime candidates capable of reaching hyperabundance as they are edge adapted, with gregarious social structure, omnivorous diets, rapid reproduction and high tolerance to human proximity. Compared to intact interior forests, population densities in degraded forests were 148% and 87% higher for wild boar and macaques, respectively. In landscapes with >60% oil palm coverage, wild boar and pig-tailed macaque estimated abundances were 337% and 447% higher than landscapes with <1% oil palm coverage, respectively, suggesting marked demographic benefits accrued by crop raiding on calorie-rich food subsidies. There was extreme community dominance in forest landscapes with >20% oil palm cover where two pig and two macaque species accounted for >80% of independent camera trap detections, leaving <20% for the other 85 mammal species >1 kg considered. Establishing the population trends of pigs and macaques is imperative since they are linked to cascading impacts on the fauna and flora of local forest ecosystems, disease and human health, and economics (i.e., crop losses). The severity of potential negative cascading effects may motivate control efforts to achieve ecosystem integrity, human health and conservation objectives. Our review concludes that the rise of native generalists can be mediated by specific types of degradation, which influences the ecology and conservation of natural areas, creating both positive and detrimental impacts on intact ecosystems and human society., (© 2023 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.)

A survey evaluated 2,300 healthcare workers following the first dose of a coronavirus disease 2019 (COVID-19) vaccine in a tertiary-quaternary hospital in São Paulo, Brazil. Adherence to protective measures following vaccination was compared to previous non-work-related behaviors. Younger age, previous COVID-19, and burnout symptoms were associated with reduced adherence to mitigation measures.

Developing high-quality scientific research will be most effective if research communities with diverse skills and interests are able to share information and knowledge, are aware of the major challenges across disciplines, and can exploit economies of scale to provide robust answers and better inform policy. We evaluate opportunities and challenges facing the development of a more interactive research environment by developing an interdisciplinary synthesis of research on a single geographic region. We focus on the Amazon as it is of enormous regional and global environmental importance and faces a highly uncertain future. To take stock of existing knowledge and provide a framework for analysis we present a set of mini-reviews from fourteen different areas of research, encompassing taxonomy, biodiversity, biogeography, vegetation dynamics, landscape ecology, earth-atmosphere interactions, ecosystem processes, fire, deforestation dynamics, hydrology, hunting, conservation planning, livelihoods, and payments for ecosystem services. Each review highlights the current state of knowledge and identifies research priorities, including major challenges and opportunities. We show that while substantial progress is being made across many areas of scientific research, our understanding of specific issues is often dependent on knowledge from other disciplines. Accelerating the acquisition of reliable and contextualized knowledge about the fate of complex pristine and modified ecosystems is partly dependent on our ability to exploit economies of scale in shared resources and technical expertise, recognise and make explicit interconnections and feedbacks among sub-disciplines, increase the temporal and spatial scale of existing studies, and improve the dissemination of scientific findings to policy makers and society at large. Enhancing interaction among research efforts is vital if we are to make the most of limited funds and overcome the challenges posed by addressing large-scale interdisciplinary questions. Bringing together a diverse scientific community with a single geographic focus can help increase awareness of research questions both within and among disciplines, and reveal the opportunities that may exist for advancing acquisition of reliable knowledge. This approach could be useful for a variety of globally important scientific questions., (© 2010 The Authors. Biological Reviews © 2010 Cambridge Philosophical Society.)