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Cochabamba, Bolivia

Pickles R.S.A.,UK Institute of Zoology | Pickles R.S.A.,University of Kent | Groombridge J.J.,University of Kent | Zambrana Rojas V.D.,Asociacion FaunAgua | And 7 more authors.
Molecular Phylogenetics and Evolution | Year: 2011

The giant otter, Pteronura brasiliensis, occupies a range including the major drainage basins of South America, yet the degree of structure that exists within and among populations inhabiting these drainages is unknown. We sequenced portions of the mitochondrial DNA (mtDNA) cytochrome b (612. bp) and control region (383. bp) genes in order to determine patterns of genetic variation within the species. We found high levels of mtDNA haplotype diversity (h=0.93 overall) and support for subdivision into four distinct groups of populations, representing important centers of genetic diversity and useful units for prioritizing conservation within the giant otter. We tested these results against the predictions of three hypotheses of Amazonian diversification (Pleistocene Refugia, Paleogeography, and Hydrogeology). While the phylogeographic pattern conformed to the predictions of the Refugia Hypothesis, molecular dating using a relaxed clock revealed the phylogroups diverged from one another between 1.69 and 0.84. Ma, ruling out the influence of Late Pleistocene glacial refugia. However, the role of Plio-Pleistocene climate change could not be rejected. While the molecular dating also makes the influence of geological arches according to the Paleogeography Hypothesis extremely unlikely, the recent Pliocene formation of the Fitzcarrald Arch and its effect of subsequently altering drainage pattern could not be rejected. The data presented here support the interactions of both climatic and hydrological changes resulting from geological activity in the Plio-Pleistocene, in shaping the phylogeographic structure of the giant otter. © 2011 Elsevier Inc. Source


Pickles R.S.A.,UK Institute of Zoology | Pickles R.S.A.,University of Kent | Groombridge J.J.,University of Kent | Rojas V.D.Z.,Asociacion FaunAgua | And 4 more authors.
Conservation Genetics | Year: 2012

We assessed levels of genetic diversity and investigated patterns of population structure in three remnant populations of the endangered giant otter, Pteronura brasiliensis, using microsatellite loci. All populations displayed moderate to low levels of heterozygosity and allelic richness (H O 0. 56-0. 57, A R 4. 00-5. 15) and effective population sizes were low (N E 10. 8-54) although only the Iténez population exhibited the signature of a genetic bottleneck. Population structure analyses revealed a pattern in which the populations of the Upper Amazon, Orinoco and Essequibo drainages comprised partially differentiated segments of a northern South American metapopulation, whereas the population of the Iténez appeared isolated. The observed patterns are congruent with previous mitochondrial DNA analysis which suggested the Iténez and northern South American groups constitute two evolutionary significant units. The results presented here should be considered in planning future policies aiming to manage the recovery of the giant otter across its range. © 2011 Springer Science+Business Media B.V. Source


Macnaughton A.E.,World Fisheries Trust | Carvajal-Vallejos F.M.,Asociacion FaunAgua | Carvajal-Vallejos F.M.,Higher University of San Simon | Argote A.,Asociacion FaunAgua | And 4 more authors.
Maritime Studies | Year: 2015

Species introduction, combined with changing access rules, increasing demand, and new road and dam infrastructure, are contributing to remarkable changes in Bolivian Amazon fisheries. This paper examines community responses to the appearance of a commercially valuable introduced fish species, Arapaima cf. gigas (“paiche”) in the Bolivian Amazon. Until the end of the 20th century, fisheries in this region were relatively low intensity, focused in rivers on a small number of native large-sized species by an urban-based commercial fishing fleet, and in floodplain lakes on a high diversity of native medium-sized species for subsistence by rural indigenous communities. In the seventies, Arapaima cf. gigas was introduced from Peru and has since invaded a significant portion of the Madre de Dios and Beni basins in northern Bolivia. This species now represents up to 80 % of commercial catches for the region. Occupying primarily floodplain lakes, many of which are located within indigenous territories, it has created economic opportunities and stimulated conflicts. The evolution of fisheries in one indigenous Tacana community is described, and the perspectives of local fishers are explored. Results suggest that while the new resource has strengthened incipient community-level organization, the current capture strategies and management mechanisms may not be conducive to sustainability or equitable distribution of returns. Commercial fisheries targeting a set of native species have been replaced by a single-species fishery in this community, raising questions about how the changes both in the resource-base and associated livelihood strategies are impacting system resilience. Ecosystem impacts of the introduction remain unclear. Paiche is viewed both as a potential threat and an opportunity by indigenous fishers. The management of this introduced species for a maximum social benefit and minimal environmental damage are topical concerns for communities and government actors and should be treated carefully considering local and broader, regional-scale implications. © 2015, Macnaughton et al. Source

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