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Valuing visitor services and access to protected areas: The case of Nyungwe National Park in Rwanda

Policymakers and recreation site managers use changes in fee structure, either introducing park entrance fees or increasing existing ones, to generate revenues, improve services, and reduce damages associated with over-use. Increase in park usage fee, however, can make the park inaccessible to certain segments of tourists. Understanding park users' response to changes in fees and its implication on park use equity is, thus, important to achieving a park's full potential in a socially and environmentally responsible way.

Rapid and direct recoveries of predators and prey through synchronized ecosystem management

One of the twenty-first century’s greatest environmental challenges is to recover and restore species, habitats and ecosystems. The decision about how to initiate restoration is best-informed by an understanding of the linkages between ecosystem components and, given these linkages, an appreciation of the consequences of choosing to recover one ecosystem component before another. However, it remains difficult to predict how the sequence of species’ recoveries within food webs influences the speed and trajectory of restoration, and what that means for human well-being.

Tracing the influence of land-use change on water quality and coral reefs using Bayesian model

Coastal ecosystems can be degraded by poor water quality. Tracing the causes of poor water quality back to land-use change is necessary to target catchment management for coastal zone management. However, existing models for tracing the sources of pollution require extensive data-sets which are not available for many of the world's coral reef regions that may have severe water quality issues. Here we develop a hierarchical Bayesian model that uses freely available satellite data to infer the connection between land-uses in catchments and water clarity in coastal oceans.

Unconventional oil and gas spills: Risks, mitigation priorities, and state reporting requirements

Rapid growth in unconventional oil and gas (UOG) has produced jobs, revenue, and energy, but also concerns over spills and environmental risks. We assessed spill data from 2005 to 2014 at 31 481 UOG wells in Colorado, New Mexico, North Dakota, and Pennsylvania. We found 2−16% of wells reported a spill each year. Median spill volumes ranged from 0.5 m3 in Pennsylvania to 4.9 m3 in New Mexico; the largest spills exceeded 100 m3. Seventy-five to 94% of spills occurred within the first three years of well life when wells were drilled, completed, and had their largest production volumes.

Evaluating signals of oil spill impacts, climate, and species interactions in Pacific herring and Pacific salmon populations in Prince William Sound and Copper River, Alaska

The Exxon Valdez oil spill occurred in March 1989 in Prince William Sound, Alaska, and was one of the worst environmental disasters on record in the United States. Despite long-term data collection over the nearly three decades since the spill, tremendous uncertainty remains as to how significantly the spill affected fishery resources. Pacific herring (Clupea pallasii) and some wild Pacific salmon populations (Oncorhynchus spp.) in Prince William Sound declined in the early 1990s, and have not returned to the population sizes observed in the 1980s.

Carbon and biodiversity impacts of intensive versus extensive tropical forestry

How should we meet the demand for wood while minimizing climate and biodiversity impacts? We address this question for tropical forest landscapes designated for timber production. We model carbon and biodiversity outcomes for four archetypal timber production systems that all deliver the same volume of timber but vary in their spatial extent and harvest intensity. We include impacts of variable deforestation risk (secure land tenure or not) and alternative harvesting practices (certified reduced-impact logging methods or not).

Opportunities and constraints for implementing integrated land-“sea management on islands

Despite a growing body of literature on integrated land–sea management (ILSM), very little critical assessment has been conducted in order to evaluate ILSM in practice on island systems. Here we develop indicators for assessing 10 integrated island management principles and evaluate the performance of planning and implementation in four island ILSM projects from the tropical Pacific across different governance structures.

Depletion of heterogeneous source species pools predicts future invasion rates

Upstream solutions to coral reef conservation: The payoffs of smart and cooperative decision-making

Land-based source pollutants (LBSP) actively threaten coral reef ecosystems globally. To achieve the greatest conservation outcome at the lowest cost, managers could benefit from appropriate tools that evaluate the benefits (in terms of LBSP reduction) and costs of implementing alternative land management strategies. Here we use a spatially explicit predictive model (InVEST-SDR) that quantifies change in sediment reaching the coast for evaluating the costs and benefits of alternative threat-abatement scenarios.

Goliath catfish spawning in the far western Amazon confirmed by the distribution of mature adults, drifting larvae and migrating juveniles

We mapped the inferred long-distance migrations of four species of Amazonian goliath catfishes (Brachyplatystoma rousseauxii, B. platynemum, B. juruense and B. vaillantii) based on the presence of individuals with mature gonads and conducted statistical analysis of the expected long-distance downstream migrations of their larvae and juveniles. By linking the distribution of larval, juvenile and mature adult size classes across the Amazon, the results showed: (i) that the main spawning regions of these goliath catfish species are in the western Amazon; (ii) at least three species—B.