Bird Extinctions in Atlantic Forest Fragments of the Viçosa Region, Southeastern Brazil

Abstract:   We studied the conservation status of Atlantic forest birds in 43 forest fragments ranging in size from 1 to 384 ha in the Viçosa region of southeastern Brazil. We compared data from 15 years of field work with historical records from the region, mainly originating from specimens collected by João Moojen during the 1930s. We used published studies associated with museum data and current field work to assess the decline of forest birds during the last 70 years and to relate their disappearance to forest fragmentation and destruction. At least 28 bird species have become locally extinct, 43 are critically endangered, and 25 are vulnerable, representing 60.7% of the original forest bird community known to exist in the region. Vulnerability to fragmentation differed among guilds, forest strata, and endemicity status. Birds that feed on fruit and seeds, and those that feed on insects, were more threatened than omnivores and carnivores. Nectarivorous species were less threatened than other guilds. Moreover, terrestrial and understory birds or birds using only one forest stratum also were more likely to have been threatened. Finally, Atlantic forest endemics were more likely to have become extinct than nonendemic species. In general, sensitivity to environmental disturbance at the local level was similar to the predicted vulnerability to regional disturbance derived from the literature. Our results indicate that a serious decline of Atlantic forest birds is underway and that many other species of birds, not previously recognized as threatened, are of conservation concern .     

Political benefits as barriers to assessment of environmental costs in Brazil's Amazonian development planning: The example of the Jatapu Dam in Roraima

Development projects are rapidly changing the landscape in Brazilian Amazonia. Environmental impact assessments have been required since 1986, and the regulatory system is evolving as precedents are set by each new development project. The Jatapu Dam in Roraima provides an illustration of underlying impediments to assessment of environmental costs and to due consideration being given to these assessments when decisions are made. The high priority placed on the dam by the Roraima state government is unexplainable in terms of economic returns. The place of the dam in a long-term political strategy provides the best of several possible explanations, any one of which is incompatible with a rational weighing of economic and environmental costs and benefits. A number of lessons can be drawn from the experience of Jatapu, but some of the problems have no solution. The barriers to rational decision making illustrated by Jatapu apply to development projects in many parts of the world.     

Social features of energy production and use in Brazil: Goals for a sustainable energy future

This paper focuses on the social features of ene rgy production and use in Brazil and discusses the role of the energy policy goals of accessibility, affordability and acceptability in defining a sustainable energy future for the country. The major findings are that social inequalities in Brazil regarding energy use continue to be substantial and important. This can be explained by the fact that, although recent decades have seen significant improvements in energy accessibility all over the country, much more needs to be done to provide affordable, and socially acceptable modern energy carriers to all socio‐economic groups in all regions.     

A System Dynamics Model for the Environmental Management of the Sepetiba Bay Watershed, Brazil

In the recent past, the Sepetiba Bay watershed, located in the Rio de Janeiro State, Brazil has experienced rapid industrial development and population growth, as well as an increase in water pollution and environmental degradation. To analyze the complex interrelationships among the agents affecting the Sepetibza Bay environment, a system dynamics model was developed. The model builds on extensive studies conducted for the watershed, and simulates different hypotheses of economic growth and of demographic expansion. Thus, it can be used as a decision support tool for the identification of investment priorities and policy analyses under various scenarios. In order to provide a comprehensive approach to the environmental management of the Sepetiba Bay watershed, the model had to consider only the most relevant aspects of the behavior and the key interactions among agents operating in the watershed. In this article, the model’s structure is presented together with some of its main results.     

Toxicity of the venom in three neotropical Crematogaster ants (Formicidae: Myrmicinae)

Bioassays were performed to investigate and compare the toxic properties of the contact venoms of three Neotropical Crematogaster species (C. sp. prox. abstinens, C. distans and C. brevispinosa rochai), whose main venom compounds are chemically different (long chain derivatives linked to an aldehyde or a primary acetate, and furanocembrenoid diterpenes, respectively). Different quantities of venom were topically applied on the bodies of three target insect species (workers of the termite Nasutitermes ephratae, workers of the ant Solenopsis sp., “media” and “major” workers of the ant Cephalotes pusillus). The toxicity of the venom greatly varied according to the Crematogaster species, the venom of C. b. rochai showing the highest toxic activity towards all target species. The sensitivity of the target species also greatly varied, the workers of N. ephratae showing a great sensitivity to the venoms, while the heavily armoured workers of the ant C. pusillus, particularly “major” ones, were resistant. Cuticle thickness was found to be a key factor in the resistance to the toxic effects of Crematogaster venom. Sensitivity of the target workers was also directly related to the amount of venom applied to their cuticle. Workers of C. distans were resistant to topical application of their own venom, while C. sp. prox. abstinens and C. b. rochai were not. In all cases, the venoms were slow acting, as several hours to one or even several days were needed to obtain a significant mortality. The main biological activities of the Crematogaster venom could be related to more immediate repellent properties, as recently shown with the European species C. scutellaris.     

Do Hydroelectric Dams Mitigate Global Warming? The Case of Brazil's CuruÁ-una Dam

Hydroelectric dams in tropical forest areas emit greenhouse gases, as illustrated by the Curuá-Una Dam in the Amazonian portion of Brazil. Emissions include carbon dioxide from decay of the above-water portions of trees that are left standing in the reservoir and methane from soft vegetation that decays under anaerobic conditions on the bottom of the reservoir, especially macrophytes (water weeds) and vegetation that grows in the drawdown zone and is flooded when the reservoir water level rises. Some methane is released from the reservoir surface through bubbling and diffusion, but larger amounts are released from water passing through the turbines and spillway. Methane concentration in the water increases with depth, and the turbines and spillway draw water from sufficient depth to have substantial methane content. In 1990 (13 years after filling), the Curuá-Una Dam emitted 3.6 times more greenhouse gases than would have been emitted by generating the same amount of electricity from oil.     

Environmental, land-use and economic implications of Brazilian sugarcane expansion 1996–2006

Governments are promoting biofuels and the resulting changes in land use and crop reallocation to biofuels production have raised concerns about impacts on environment and food security. The promotion of biofuels has also been questioned based on suggested marginal contribution to greenhouse gas emissions reduction, partly due to induced land use change causing greenhouse gas emissions. This study reports how the expansion of sugarcane in Brazil during 1996–2006 affected indicators for environment, land use and economy. The results indicate that sugarcane expansion did not in general contribute to direct deforestation in the traditional agricultural region where most of the expansion took place. The amount of forests on farmland in this area is below the minimum stated in law and the situation did not change over the studied period. Sugarcane expansion resulted in a significant reduction of pastures and cattle heads and higher economic growth than in neighboring areas. It could not be established to what extent the discontinuation of cattle production induced expansion of pastures in other areas, possibly leading to indirect deforestation. However, the results indicate that a possible migration of the cattle production reached further than the neighboring of expansion regions. Occurring at much smaller rates, expansion of sugarcane in regions such as the Amazon and the Northeast region was related to direct deforestation and competition with food crops, and appear not to have induced economic growth. These regions are not expected to experience substantial increases of sugarcane in the near future, but mitigating measures are warranted.     

Organochlorine contaminants in albatrosses and petrels during migration in South Atlantic Ocean

Albatrosses and petrels (Procellariiformes) are migratory oceanic birds of considerable conservational interest. Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were assessed in the subcutaneous fat, liver and muscle of 100 birds belonging to eight species of Procellariiformes collected during their migration period in southern Brazil, one of the most important feeding areas for these species. Although the profiles of PCBs and OCPs were similar among the individuals, with predominance of penta, hexa and heptachlorobiphenyls and p′p-DDE, organochlorine concentrations exhibited a high degree of intra-species variability. The influence of body condition during the migration period in the distribution of organochlorine contaminants was also evaluated, showing that it is a significant factor in the variation and redistribution of these compounds in the tissues of these birds. The intense use of lipid reserves associated to the contamination from organochlorine compounds could be a troubling factor for seabirds with extended breeding periods and that spend most of their lives at sea migrating long distances, such as most of Procellariiformes. Studies on contamination are necessary to improve the knowledge of the threats to these birds and their populations as well as to contribute with information about persistent organic pollutants in the South Atlantic marine environment.     

Impact of foot-and-mouth disease status on deforestation in Brazilian Amazon and cerrado municipalities between 2000 and 2010

Deforestation in the Brazilian Amazon released approximately 5.7 billion tons of CO₂ to the atmosphere between 2000 and 2010, and 50–80% of this deforestation was for pasture. Most assume that increasing demand for cattle products produced in Brazil caused this deforestation, but the empirical work to-date on cattle documents only correlations between cattle herd size, pasture expansion, cattle prices, and deforestation. This paper uses panel data on deforestation and foot-and-mouth disease (FMD) status—an exogenous demand shifter—to estimate whether changes in FMD status caused new deforestation in municipalities in the Brazilian Amazon and cerrado biomes during the 2000–2010 period. Results suggest that, on average, becoming certified as FMD-free caused a temporary spike in deforestation in the 2 years after a municipality became FMD-free, but caused subsequent deforestation to decline relative to infected municipalities during the 2000–2010 period.     

Framing community forestry challenges with a broader lens: case studies from the Brazilian Amazon

Community forestry initiatives have been shown to reduce rural poverty while promoting the conservation and sustainable use of forests. However, a number of challenges face communities wanting to initiate or maintain formal, community-based forest management. Through a grounded theory approach, this paper uses three case studies of community forest management models in the eastern Amazon to create a framework showing challenges faced by communities at different phases of formal management. The framework shows that, in the development phase, four root problems (land ownership, knowledge acquisition, community organization, and adequate capital) need to be addressed to obtain legal management permission. With this permission in hand, further challenges to operationalization are presented (deterring illegal loggers, maintaining infrastructure, obtaining necessary managerial skills and accessing markets). The interrelatedness of these challenges emphasizes that all challenges need to be addressed in a holistic manner for communities to maintain a profitable and self-sufficient operation. This contradicts current development approaches that only address part of this framework. The framework proposed here can be used as a starting point for community forestry initiatives in other regions.