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Effective management refers to the ability of a protected area or indigenous territory to meet its objectives, particularly as they relate to the protection of biodiversity and forest cover. Effective management is achieved through a process of consolidation, which among other things requires legally protecting sites, integrating sites into land-use planning, developing and implementing management and resource-use plans, and securing long-term funding to pay for recurrent costs. Effectively managing all protected areas and indigenous territories in the Amazon may be needed to avoid a deforestation tipping point beyond which regional climatic feedbacks and global climate change interact to catalyze irreversible drying and savannization of large areas. At present, protected areas and indigenous territories cover 45.5% (3.55 million km2 ) of the Amazon, most of the 60-70% forest cover required to maintain hydrologic and climatic function. Three independent evaluations of a long-term large-scale philanthropic initiative in the Amazon yielded insights into the challenges and advances toward achieving effective management of protected areas and indigenous territories. Over the life of the initiative, management of sites has improved considerably, particularly with respect to management planning and capacity building, but few sites are effectively managed and many lack sufficient long-term financing, adequate governance, support of nongovernmental organizations, and the means to withstand economic pressures. The time and money required to complete consolidation is still poorly understood, but it is clear that philanthropic funding is critical so long as essential funding needs are not met by governments and other sources, which could be on the order of decades. Despite challenges, it is encouraging that legal protection has expanded greatly and management of sites is improving steadily. Management of protected areas in other developing countries could be informed by improvements that have occurred in Amazonian countries.

Hispaniola Island has both a high level of amphibian endemism, and a high level of habitat degradation due to agriculture, infrastructure development, and extractive industries. The objective of this work was to evaluate the capacity of Dominican Republic's current network of protection to maintain the habitat of four species of amphibians endemic to Hispaniola ( Osteopilus pulchrilineatus , Osteopilus vastus , Hypsiboas heilprini , and Eleutherodactylus flavescens ). Spatial analysis was performed to relate observations of the target species to environmental factors using a maximum entropy algorithm (Maxent). Results of this analysis produced maps of probability of occurrence for each species. Analysis of habitat degradation was based on a change analysis of vegetation, by evaluating trends in the normalized difference vegetation index (NDVI) between 2000 and 2011. Results show that forest loss and species habitat loss within protected areas are smaller but similar to those extracted for the country as a whole, suggesting that the current protected area network is not effective for the maintenance of the habitat of the amphibians analyzed. Enforcement of established protection and restoration within current protected areas could facilitate the protection of up to 25.7% of target amphibian habitat. The methodologies presented here can be applied to measure biodiversity offset effectiveness.

Effective management refers to the ability of a protected area or indigenous territory to meet its objectives, particularly as they relate to the protection of biodiversity and forest cover. Effective management is achieved through a process of consolidation, which among other things requires legally protecting sites, integrating sites into land-use planning, developing and implementing management and resource-use plans, and securing long-term funding to pay for recurrent costs. Effectively managing all protected areas and indigenous territories in the Amazon may be needed to avoid a deforestation tipping point beyond which regional climatic feedbacks and global climate change interact to catalyze irreversible drying and savannization of large areas. At present, protected areas and indigenous territories cover 45.5% (3.55 million km

Consumer demand for the premier neotropical luxury timber, big-leaf mahogany (Swietenia macrophylla), has driven boom-and-bust logging cycles for centuries, depleting local and regional supplies from Mexico to Bolivia. We revise the standard historic range map for mahogany in South America and estimate the extent to which commercial stocks have been depleted using satellite data, expert surveys, and sawmill processing center data from Brazil. We estimate an historic range of 278 million hectares spanning Venezuela to Bolivia, 57% of this in Brazil. Approximately 58 million hectares (21%) of mahogany's historic range had been lost to forest conversion by 2001. Commercial populations had been logged from at least 125 million more hectares, reducing the commercial range to 94 million hectares (34% of historic). Surviving stocks are extremely low-density populations in remote regions representing a smaller fraction of historic stocks than expected based on estimated current commercial range. Our method could advance international policy debates such as listing proposals for CITES Appendices by clarifying the commercial and conservation status of high-value timber species similar to mahogany about which little information is available. The fate of remaining mahogany stocks in South America will depend on transforming current forest management practices into sustainable production systems.

In recent years, donors to biodiversity conservation projects have sought greater accountability, using professional evaluators to help assess the degree to which grantees are achieving conservation objectives. One of the most formidable challenges evaluators face is the time required both for ecological systems to respond to management interventions and over which grantees must maintain their biodiversity conservation gains. The authors present a simple methodology, called limiting factors analysis, which was developed during the course of evaluating several large portfolios of conservation projects. The method is a practical basis for rapidly assessing whether current conditions are likely to prevent grantees from achieving their long-term objectives. Use of the methodology is illustrated with examples from recent evaluations of the Andes Amazon Initiative and the Columbia Basin Water Transactions Program. © Wiley Periodicals, Inc.

Decades of research have had virtually no impact on harvesting rates or harvesting practices for mahogany (Swietenia spp.), among the most valuable timber species of Latin America.Despite the existence of science-based regulations, mahogany is rapidly and often illegally harvested to the point where its density is so depleted that logging is no longer commercially viable.The lack of influence of science on forest management is not a result of scientific deficiency; rather, it is a political and economic failure to implement existing forest management policies. Until political will and regulatory capacity for enforcement exist or until buyers insist on meaningful verification that shipments were legally obtained, there is little incentive for reform and policies regulating the use of mahogany will not be implemented.Thus, under present conditions, there is little opportunity for science to influence the fate of mahogany.The case study of mahogany provides an excellent example not only of the difficulty for research to inform forest management, but also of demonstrating the key elements necessary for effective implementation of any forest policy. 2003 Elsevier B.V. All rights reserved.

Results from experimentally manipulating harvest intensity from 1 to 6 trees ha−1 are reported for the Chimanes Forest, Bolivia. The area of vegetation damaged by logging was a quadratic increasing function of harvest intensity. This was because at higher harvest intensities, skidders used existing trails for log extraction, and trees tended to fall at least partially on existing gaps, so per tree damage declined with increasing harvest. The median distance of residual forest to the nearest gap after logging decreased from 24.9 m at 1 tree ha−1, to 8.3 m at 6 trees ha−1. Both harvest mortality and total mortality (harvest plus damage to the residual stand) were quadratic increasing functions of harvest intensity when expressed in terms of basal area. Residual basal area damage was a very low because mortality was concentrated on the smaller size classes, which individually contribute little to total basal area. Of three commercial species surveyed, only the seedlings and saplings of Hura crepitans showed a significant positive relationship between relative growth rate and harvest intensity. Finally, tree species loss was relatively low and constant across a range of plot sizes and harvest intensities, but reductions in species diversity (H′) depended on the intensity of harvest and plot size.

Mahogany (Swietenia macrophylla King) regenerates in areas of erosion on high terraces and in forest killed by flooding and deposition of alluvial sediments in the Chimanes Forest, Bolivia. These hydrological disturbances are patchy, and only one of five stands of mahogany that we inventoried was regenerating. Mahogany survives these disturbances significantly better than the common tree species. The long time between disturbances appears to favour late maturation. Mahogany trees allocate little photosynthates to reproduction until they are very large emergents, at least 80 cm in diameter. The episodic nature of the regeneration sites means that mahogany stands are composed of one or a few cohorts, which are vulnerable to overharvesting, particularly with the current use of a minimum cutting diameter to regulate harvest. The delayed onset of fecundity means that the small trees that escape harvest are not very fecund, resulting in minimal seed input to logged forest. Only 7–9% of the gaps created by logging contain natural regeneration after 20 + yr. A successful management plan for mahogany would entail a monocyclic harvest, with a rotation age of 100 + years, the estimated time that it takes for trees to achieve commercial size in natural forest. Since the number of seed trees that will be left is small, they should be concentrated in sites that are likely to be conducive to natural regeneration, such as near rivers and flood damaged forest. Seed production will be maximized for a given basal area (opportunity cost to loggers) if trees c. 110 cm dbh are selected as seed trees. The mahogany stocks in the Chimanes Forest are nearly exhausted, but the findings of this study could be used to help rebuild the mahogany populations, or to design management plans for the commercial species that have similar ecologies to mahogany.

Mahogany (Swietenia macrophyllaKing) regenerates in areas of erosion on high terraces and in forest killed by flooding and deposition of alluvial sediments in the Chimanes Forest, Bolivia. These hydrological disturbances are patchy, and only one of five stands of mahogany that we inventoried was regenerating. Mahogany survives these disturbances significantly better than the common tree species. The long time between disturbances appears to favour late maturation. Mahogany trees allocate little photosynthates to reproduction until they are very large emergents, at least 80 cm in diameter. The episodic nature of the regeneration sites means that mahogany stands are composed of one or a few cohorts, which are vulnerable to overharvesting, particularly with the current use of a minimum cutting diameter to regulate harvest. The delayed onset of fecundity means that the small trees that escape harvest are not very fecund, resulting in minimal seed input to logged forest. Only 7–9% of the gaps created by logging contain natural regeneration after 20+ yr. A successful management plan for mahogany would entail a monocyclic harvest, with a rotation age of 100+ years, the estimated time that it takes for trees to achieve commercial size in natural forest. Since the number of seed trees that will be left is small, they should be concentrated in sites that are likely to be conducive to natural regeneration, such as near rivers and flood damaged forest. Seed production will be maximized for a given basal area (opportunity cost to loggers) if treesc. 110 cm dbh are selected as seed trees. The mahogany stocks in the Chimanes Forest are nearly exhausted, but the findings of this study could be used to help rebuild the mahogany populations, or to design management plans for the commercial species that have similar ecologies to mahogany.

There are few if any examples of the demonstrably sustainable extraction of either timber or non—timber forest products. Even well—known products such as brazil nuts and mahogany lack a sufficient knowledge base to design a sustainable extraction system. Potential extraction systems for timber and non—timber forest products from tropical forests should be evaluated both in terms of their sustainability and their impact at the ecosystem level. The impact of forest product harvest on the demographics of the target species can be explored with the use of mathematical models, although we still lack an adequate understanding of some of the basic processes that are structuring tropical tree communities. Matrix models are relatively quick to construct, and they may be appropriate for modeling the dynamics of populations that are harvested without introducing large changes to the ecosystem, while individual—based mechanistic models are more appropriate for modeling the effects of harvest that cause large changes ...

Selective harvesting in tropical forests has been shown to cause considerable damage to residual trees in stands that have relatively high densities of commercial trees. To complement existing studies, we measured forest damage caused by the selective harvesting of mahogany ( Swietenia macrophylla ), a very low density species in the Bosque Chimanes, Bolivia. Secondary damage along main roads and skid trails accounted for most of the damage measured in the study site. Total damage was low (4.39% of the study area), but results from our simulation model suggested that damage could be decreased by up to 25% by requiring main roads and skid trails to be linear. We used our simulation model to investigate the relationship between harvest intensity and forest damage. At low harvest intensities, most forest damage occurs from the construction of main roads. As harvest intensity increases, secondary damage from skid trails and tree felling comes to dominate forest damage. Overall, less damage will result to the forest for a given harvest volume if the harvest area is reduced and harvest intensity increased. Additional benefits to increasing harvest intensity are that re-entry into the logged site can be delayed, allowing the forest more time to recover, and regeneration of light-demanding species such as mahogany can be enhanced. The main impediment to increasing the harvest intensity in selective harvesting operations in Latin America is the lack of international markets for lesser known species, although there is some local and national demand.

Much current controversy exists about the role that foreign debt plays in deforestation in Latin America. In an attempt to familiarize concerned biologists with this issue, we present an overview of the proposed positive and negative effects that foreign debt has had on neotropical forest loss. From the literature, we identify three main hypotheses as to how the large external debts of developing Latin American countries may contribute to deforestation. We find that (1) countries have not increased exports of tropical timber and beef in response to rising debt; (2) external debts have contributed to economic stagnation and an associated increase in poverty in Latin America, which in turn has caused the degradation of marginal lands, but the role of debt in this process cannot be isolated from other important contributing factors; and (3) while debt payments have probably led to governmental budget cutbacks in environmental spending, historically spending in these areas has not been high. On the positive side, we found that (1) innovative debt-for-nature swaps have traded devalued debt for a commitment and funds to create and protect nature reserves; and (2) debt could be exchanged for forestry and agricultural sectoral reform, which would have very large positive effects on the conservation and management of forests. En el presente existe mucha controversia sobre el rol que la deuda externa juega en la deforestacion de America Latina. En un intento de familiarizar a biologos interesados en este tema nosotros presentamos una resena sobre los efectos positivos y negativos que la deuda externa ha tenido en la perdida de selvas Neotropicales. A partir de la literatura sobre el tema, nosotros identificamos tres hopotesis principales sobre como las grandes deudas externas de los paises en vias de dasarrollo de America Latina contribuirian a la deforestacion. Encontramos que (1) los paises no han incrementado las exportaciones de madera tropical y carne como respuesta a la creciente deuda, (2) las deudas externas han contribuido al estancamiento economico y al asociado incremento de la pobreza en America Latina, lo que a su vez ha causado la degradacion de las tierras marginales; sin embargo, el rol de la deuda en este proceso no puede ser aislado de otros importantes factores cotribuyentes, y (3) si bien los pagos de la deuda probablemente han producido recortes en el presupuesto de gastos relativos a medio ambiente, historicamente los gastos en estas areas no han sido altos. Desde un punto de vista positivo, (1) el innovativo troque de deuda por naturaleza ha intercambiado deuda devaluada por un compromiso y fondos para crear y proteger reservas naturales y (2) la deuda puede ser intercambiada por una reforma en los sectores de bosques y agricultura, la cual puede tener un gran efecto positivo en la conservacion manejo de los bosques.

Allozyme analysis was used to measure genetic variation, population differentiation, and the mating system in natural populations of big-leaf mahogany from Bolivia. We sampled seeds from individual maternal trees in four mahogany populations separated by as much as 100km. Data were analyzed based on estimated maternal genotypes and on randomly drawn progeny arrays from known mothers. The analysis indicated that mahogany in this part of its range was characterized by genetic variation similar to that found in other common tropical tree species. The average gene diversity in populations ranged from H e = 0.200 to H e = 0.205. The G ST values among these four populations ranged from 0.034 to 0.063, indicating rather low population differentiation on a scale of 40 to 100km. We also used progeny arrays to estimate the mahogany mating system in one population. Mahogany seeds were completely outcrossed; the multilocus outcrossing estimate was t m = 1.038 (SE = 0.024). Mahogany thus con forms to the model emerging from other genetic studies of tropical trees: a long-lived woody species, with a highly outcrossed breeding system that generates the potential for significant pollen movement, and high variation, mostly within regionally distributed populations. We discuss the implications of these data for conserving and managing populations of mahogany and other tropical trees.

The role that episodic flooding and deposition of alluvial sediments might play in maintaining big-leaf mahogany and associated timber species was studied in Bolivian Amazonian forests. Big-leaf mahogany, Spanish cedar, Hura crepitans, and Calophyllum brasiliense had significantly higher densities near active rivers than at sites distant from rivers. Alluvial deposition at one site resulted in a median mortality of 12% of the basal area of the forest (all tree species ≥5cmdbh), but mortality ranged up to 100%. This reduction in basal area caused large and significant increases in canopy openness. Big-leaf mahogany and H. crepitans showed strong increases in height growth with increasing canopy openness. Growth of the mahogany saplings projected by using the growth curves and light environments quantified in this study suggest that this type of fluvial disturbance was large enough to explain their regeneration. Stand structures and growth curves for all three of the associated species suggested that conditions created by episodic flooding and deposition also might improve their regeneration.

Although bigleaf mahogany [Swietenia macrophylla King (Meliaceae)] is the premier timber species of Latin America, its exploitation is unsustainable because of a pattern of local depletion and shifting supply. We surveyed experts on the status of mahogany in Bolivia and Peru, the world's past and present largest exporters. Bolivia no longer has commercially viable mahogany (trees > 60 cm diameter at breast height) across 79% of its range. In Peru, mahogany's range has shrunk by 50%, and, within a decade, a further 28% will be logged out. Approximately 15% of the mahogany range in these two countries is protected, but low densities and illegal logging mean that this overestimates the extent of mahogany under protection. The international community can support mahogany conservation by funding park management and by encouraging independent verification of the legality of mahogany in trade. Our findings demonstrate that a systematic expert survey can generate reliable and cost-effective information on the status of widespread species of concern and help to inform appropriate management policy. Recommended citation: Kometter, R. F., M. Martinez, A. G. Blundell, R. E. Gullison, M. K. Steininger, and R. E. Rice. 2004. Impacts of unsustainable mahogany logging in Bolivia and Peru. Ecology and Society 9(1): 12. [online] URL: http://www.ecologyandsociety.org/vol9/iss1/art12

We assessed the impacts of anthropogenic threats on 93 protected areas in 22 tropical countries to test the hypothesis that parks are an effective means to protect tropical biodiversity. We found that the majority of parks are successful at stopping land clearing, and to a lesser degree effective at mitigating logging, hunting, fire, and grazing. Park effectiveness correlates with basic management activities such as enforcement, boundary demarcation, and direct compensation to local communities, suggesting that even modest increases in funding would directly increase the ability of parks to protect tropical biodiversity.

New science underscores the value of a climate policy initiative to reduce emissions from tropical deforestation.

Underfunding jeopardizes the ability of protected areas to safeguard biodiversity and the benefits that intact nature provides to society. In this article, we evaluate the cost of effectively managing all existing protected areas in developing countries, as well as the cost of expansion into high-priority new areas. We find that recent studies converge on a funding shortfall of $1 billion to $1.7 billion per year to manage all existing areas. The costs of establishing and managing an expanded protected-area system would total at least $4 billion per year over the next decade, an amount that far exceeds current spending but is well within the reach of the international community. These findings indicate the need for rapid action to mobilize significant new resources for the developing world's protected areas. In particular, this will require (a) the use of a range of tools to generate funds and improve efficiency of management; (b) greater precision and better communication of the costs and benefi...