Browsing by Subject "conservation"

Now showing 1 - 5 of 5
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    Abiotic modulators of Podocnemis unifilis (Testudines: Podocnemididae) abundances in the Peruvian Amazon
    (2011-06) Norris, D; Pitman, NCA; Gonzalez, JM; Torres, E; Pinto, F; Collado, H; Concha, W; Thupa, R; Quispe, E; Pérez, J; del Castillo, JCF
    Previous studies have demonstrated that river-based surveys can provide an inexpensive source of information for neotropical zoologists, yet little information is available to inform the application of this technique for the long term monitoring of neotropical turtle species. We aimed to fill this gap by presenting an assessment of data collected during 333 river surveys over 50 months along rivers in a newly protected area in the Peruvian Amazon. A total of 14,138 basking Podocnemis unifilis Troschel, 1848 were recorded during 13,510 km of river-based surveys. We used generalized additive models (GAMs) to explore the influence of a series of abiotic and seasonal variables on the recorded abundances at two temporal scales: monthly and per trip. Our analysis revealed that there was a significant increase in turtle abundances during the study period and we also found a significant seasonal periodicity in monthly abundances. Abiotic factors strongly influenced trip level abundances, with more individuals per kilometer recorded during sunny days in the dry season, with temperatures between 25 and 30°C. The results demonstrate that turtle populations are increasing following the establishment of the protected area and that river-based surveys are likely to be more effective when carried out within a limited set of key abiotic conditions.
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    Deforestation risks posed by oil palm expansion in the Peruvian Amazon
    (Environmental Research Letters, 2018-11-01) Vijay, V; Reid, CD; Finer, M; Jenkins, CN; Pimm, SL
    Further expansion of agriculture in the tropics is likely to accelerate the loss of biodiversity. One crop of concern to conservation is African oil palm (Elaeis guineensis). We examined recent deforestation associated with oil palm in the Peruvian Amazon within the context of the region's other crops. We found more area under oil palm cultivation (845 km2) than did previous studies. While this comprises less than 4% of the cropland in the region, it accounted for 11% of the deforestation from agricultural expansion from 2007-2013. Patches of oil palm agriculture were larger and more spatially clustered than for other crops, potentially increasing their impact on local habitat fragmentation. Modeling deforestation risk for oil palm expansion using climatic and edaphic factors showed that sites at lower elevations, with higher precipitation, and lower slopes than those typically used for intensive agriculture are at long-term risk of deforestation from oil palm agriculture. Within areas at long-term risks, based on CART models, areas near urban centers, roads, and previously deforested areas are at greatest short-term risk of deforestation. Existing protected areas and officially recognized indigenous territories cover large areas at long-term risk of deforestation for oil palm (>40%). Less than 7% of these areas are under strict (IUCN I-IV) protection. Based on these findings, we suggest targeted monitoring for oil palm deforestation as well as strengthening and expanding protected areas to conserve specific habitats.
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    Estimating the population size of lemurs based on their mutualistic food trees
    (Journal of Biogeography, 2018-11-01) Herrera, JP; Borgerson, C; Tongasoa, L; Andriamahazoarivosoa, P; Rasolofoniaina, BJR; Rakotondrafarasata, ER; Randrianasolo, JLRR; Johnson, SE; Wright, PC; Golden, CD
    Aim: Species’ distributions and abundances are primarily determined by the suitability of environmental conditions, including climate and interactions with sympatric species, but also increasingly by human activities. Modelling tools can help in assessing the extinction risk of affected species. By combining species distribution modelling of abiotic and biotic niches with population size modelling, we estimated the abundance of 19 lemur taxa in three regions, especially focusing on 10 species that are considered Endangered or Critically Endangered. Location: Madagascar. Taxa: Lemurs (Primates) and angiosperm trees. Methods: We used climate data, field samples, and published occurrence data on trees to construct species distribution models (SDM) for lemur food tree species. We then inferred the SDMs for lemurs based on the probability of occurrence of their food trees as well as climate. Finally, we used tree SDMs, topography, distance to the forest edge, and field estimates of lemur population density to predict lemur abundance in general linear models. Results: The SDMs of lemur food trees were stronger predictors of the occurrence of lemurs than climate. The predicted probability of presence of food trees, slope, elevation, and distance from the forest edge were significant correlates of lemur density. We found that sixteen species had minimum estimated abundances greater than 10,000 individuals over >1,000km2. Three lemur species are especially threatened, with less than 2,500 individuals predicted for Cheirogaleus sibreei, and heavy hunting pressure for the relatively small populations of Indri indri and Hapalemur occidentalis. Main conclusions: Biotic interactors were important variables in SDMs for lemurs, allowing refined estimates of ranges and abundances. This paper provides an analytical workflow that can be applied to other taxonomic groups to substantiate estimates of species’ vulnerability to extinction.
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    More than funders: The roles of philanthropic foundations in marine conservation governance
    (Conservation Science and Practice, 2023-05-01) Blackwatters, JE; Betsill, M; Enrici, A; Le Cornu, E; Basurto, X; Gruby, RL
    Environmental governance scholars have overlooked philanthropic foundations as influential non-state actors. This omission, along with the continued growth in funding from private foundations for conservation issues, presents important questions about what foundations do in governance spaces. To address this gap, we examine The David and Lucile Packard Foundation's involvement in Fiji and Palau in the context of the Foundation's “Western Pacific Program”—a series of coastal and marine-related investments made from 1998 to 2020. We describe and analyze six governance roles that the Packard Foundation contributed to: funding, influencing agendas, capacity-building, convening and coordinating, facilitating knowledge, and rule-making and regulation. In documenting the Packard Foundation's governance roles, we provide scholars and practitioners a conceptual framework to more systematically and strategically think about foundations as more than funders. This research helps move the conversation around conservation philanthropy beyond binary conceptions of “good” versus “bad,” and, instead, toward deeper considerations about what foundations currently do within governance systems, how they engage with diverse practitioners, as well as what they can and should do to advance conservation goals.
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    Population Genetics of Bowhead Whales (Balaena mysticetus) in the Western Arctic
    (2010) Matson, Cole W
    Bowhead whales (Balaena mysticetus) in the Bering, Chukchi, and Beaufort seas experienced a severe reduction as a result of commercial whaling in the 19th century. Since the cessation of commercial whaling, the population has recovered to a size that is approaching pre-whaling estimates. Inupiat and Yupik communities in northern and western Alaska hunt these Western Arctic (WA) bowheads along their migratory path during spring and fall. This hunting is regulated by the International Whaling Commission. Recent but preliminary analysis of available genetic data (207 whales and 10 microsatellite markers) raised the question of the presence of multiple, genetically distinct populations within the WA bowheads. Here we re-examined this question on the basis of a study of 414 whales and 22 newly developed microsatellite loci. We identified widespread departures from Hardy-Weinberg equilibrium; however, we were unable to detect significant evidence of multiple genetic populations within the WA bowheads that could explain this Hardy-Weinberg disequilibrium, particularly when compared to the strength of evidence for differentiation between WA bowheads and other populations from distant regions such as the Okhotsk Sea and eastern Canada: There was conclusive evidence of genetic differentiation among the three regions. The statistical rejection of panmixia within the WA improves our understanding of bowhead whale biology, and the lack of evidence for multiple populations within the WA enables risk-averse management of aboriginal hunting of Western Arctic bowhead whales.