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Arusha, Tanzania

Jackson A.K.,BioDiversity Research Institute | Jackson A.K.,Oregon State University | Evers D.C.,BioDiversity Research Institute | Adams E.M.,BioDiversity Research Institute | And 10 more authors.

Mercury (Hg) is a globally distributed environmental contaminant with a variety of deleterious effects in fish, wildlife, and humans. Breeding songbirds may be useful sentinels for Hg across diverse habitats because they can be effectively sampled, have well-defined and small territories, and can integrate pollutant exposure over time and space. We analyzed blood total Hg concentrations from 8,446 individuals of 102 species of songbirds, sampled on their breeding territories across 161 sites in eastern North America [geometric mean Hg concentration = 0.25 μg/g wet weight (ww), range <0.01–14.60 μg/g ww]. Our records span an important time period—the decade leading up to implementation of the USEPA Mercury and Air Toxics Standards, which will reduce Hg emissions from coal-fired power plants by over 90 %. Mixed-effects modeling indicated that habitat, foraging guild, and age were important predictors of blood Hg concentrations across species and sites. Blood Hg concentrations in adult invertebrate-eating songbirds were consistently higher in wetland habitats (freshwater or estuarine) than upland forests. Generally, adults exhibited higher blood Hg concentrations than juveniles within each habitat type. We used model results to examine species-specific differences in blood Hg concentrations during this time period, identifying potential Hg sentinels in each region and habitat type. Our results present the most comprehensive assessment of blood Hg concentrations in eastern songbirds to date, and thereby provide a valuable framework for designing and evaluating risk assessment schemes using sentinel songbird species in the time after implementation of the new atmospheric Hg standards. © 2014, Springer Science+Business Media New York. Source

Knapp E.J.,Tanzania Wildlife Research Institute | Knapp E.J.,Houghton College | Rentsch D.,Tanzania Wildlife Research Institute | Rentsch D.,University of Minnesota | And 4 more authors.

Poaching for bushmeat is a major problem for conservation of wildlife populations in many parts of Africa, including the Serengeti ecosystem in Tanzania. However, the severity of the poaching problem is often unclear because of a lack of accurate data. Directly asking people to self-report illegal activity faces the obvious problem of under-reporting. Use of arrest records from anti-poaching patrols may reflect levels of poaching activity but could also be driven by funding and quality of anti-poaching efforts. A third method, assessing poaching by asking about bushmeat consumption, is indirect, possibly subject to under-reporting, and also subject to limits on the accuracy of memory of respondents. We compare rates of poaching derived by self-assessment of poaching activities (based on household interviews), dietary recall of bushmeat consumption over a variety of time frames, and arrest records from anti-poaching units. We apply these three methods to assess poaching activities in three villages bordering protected areas on the western boundary of Serengeti National Park. Our results showed that dietary recall of bushmeat consumption and arrest records indicated similar patterns of poaching across the three villages but self-reporting differed significantly. There appear to be significant advantages to coupling results from dietary recall of bushmeat consumption and arrest records to estimate the level of poaching activity. In situations where reliable data from anti-poaching units are unavailable, cost-effective data collection of bushmeat consumption will provide a viable alternative to assess levels of poaching involvement of villages that border protected areas. Copyright © 2010 Fauna & Flora International. Source

Girvetz E.H.,Nature Conservancy | Girvetz E.H.,International Center for Tropical Agriculture | Gray E.,Nature Conservancy | Tear T.H.,Grumeti Fund | Brown M.A.,Nature Conservancy
Environmental Conservation

In the face of an already changing climate, conservation practitioners and local communities face the major challenge of how to plan for a future climate. In data-sparse areas of the world, where action is often most needed, the daunting scope of the problem can lead to inaction. This paper shows that climate adaptation planning can be accomplished successfully with publicly and globally available data by linking science and stakeholders through a facilitated process. Working with local stakeholders in the western Tanzanian Greater Mahale and Greater Gombe Ecosystems, future climate projections produced using Climate Wizard and analyses of literature provided an understanding of the climate vulnerabilities of local ecosystems and human livelihoods. Facilitated workshops enabled local stakeholders to use this information to develop conceptual models and hypotheses of change for these systems, and to identify possible modifications to conservation plans. Here, climate change planning required the modification of most current conservation strategies, developing some new strategies and abandoning others. The paper indicates that climate adaptation planning is achievable even in data-sparse rural and developing areas, but requires appropriate scientific analyses, engaged stakeholders and a facilitated process. Copyright © Foundation for Environmental Conservation 2014. Source

Bried J.,Oklahoma State University | Tear T.,Grumeti Fund | Shirer R.,The Nature Conservancy | Zimmerman C.,The Nature Conservancy | And 3 more authors.
Environmental Management

Monitoring is essential to track the long-term recovery of endangered species. Greater emphasis on habitat monitoring is especially important for taxa whose populations may be difficult to quantify (e.g., insects) or when true recovery (delisting) requires continuous species-specific habitat management. In this paper, we outline and implement a standardized framework to facilitate the integration of habitat monitoring with species recovery efforts. The framework has five parts: (1) identify appropriate sample units, (2) select measurable indicators of habitat requirements, (3) determine rating categories for these indicators, (4) design and implement appropriate data collection protocols, and (5) synthesize the ratings into an overall measure of habitat potential. Following these steps, we developed a set of recovery criteria to estimate habitat potential and initially assess restoration activities in the context of recovering an endangered insect, the Karner blue butterfly (Lycaeides melissa samuelis). We recommend basing the habitat potential grading scheme on recovery plan criteria, the latest information on species biology, and working hypotheses as needed. The habitat-based assessment framework helps to identify which recovery areas and habitat patches are worth investing in and what type of site-specific restoration work is needed. We propose that the transparency and decision-making process in endangered insect recovery efforts could be improved through adaptive management that explicitly identifies and tracks progress toward habitat objectives and ultimate population recovery. © 2014, Springer Science+Business Media New York. Source

Tear T.H.,Grumeti Fund | Stratton B.N.,Olmstead Center | Game E.T.,The Nature Conservancy | Brown M.A.,The Nature Conservancy | And 2 more authors.
Biological Conservation

Environmental conservation activities must continue to become more efficient and effective, especially in Africa where development and population growth pressures continue to escalate. Recently, prioritization of conservation resources has focused on explicitly incorporating the economic costs of conservation along with better defining the outcomes of these expenditures. We demonstrate how new global and continental data that spans social, economic, and ecological sectors creates an opportunity to incorporate return-on-investment (ROI) principles into conservation priority setting for Africa. We suggest that combining conservation priorities that factor in biodiversity value, habitat quality, and conservation management investments across terrestrial, freshwater, and coastal marine environments provides a new lens for setting global conservation priorities. Using this approach we identified seven regions capturing interior and coastal resources that also have high ROI values that support further investment. We illustrate how spatially explicit, yet flexible ROI analysis can help to better address uncertainty, risk, and opportunities for conservation, while making values that guide prioritization more transparent. In one case the results of this prioritization process were used to support new conservation investments. Acknowledging a clear research need to improve cost information, we propose that adopting a flexible ROI framework to set conservation priorities in Africa has multiple potential benefits. © 2014 The Authors. Source

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