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Santa Cruz de la Sierra, Bolivia

MacLeod R.,University of Glasgow | Herzog S.K.,Asociacion Armonia BirdLife International | Maccormick A.,University of Glasgow | Ewing S.R.,University of Glasgow | And 2 more authors.
Biological Conservation

Effective monitoring of biodiversity for conservation requires information on spatial and temporal variation in species' abundances. As conservation resources are limited, monitoring methods are required that enable rapid and cost effective data collection. There are many traditional methods of estimating absolute abundance, such as territory mapping and distance sampling. However, these typically require more time, expertise and finances than are available across much of the globe. This is especially so in the tropics, where high species richness, low densities of many species and structurally complex environments also make monitoring particularly challenging. The MacKinnon lists technique is a rapid assessment methodology designed for use in species rich environments. This method is typically used to estimate species richness, but it has also been suggested that it can generate consistent abundance indices, even when observer experience and environmental conditions vary. If this suggestion is correct, the MacKinnon lists method could be used to assess spatial or temporal changes in abundance using diverse survey data. Here, we provide the first detailed assessment of intra- and inter-observer consistency of the Mackinnon List method in generating species abundance indices that could be useful for conservation monitoring purposes. As a case study, we use one of the world's most diverse avifaunas, that of the forested Bolivian Andes. We show that MacKinnon lists can provide species abundance indices that are consistent between observers of markedly different experience of the focal avifauna (zero to six years), and between assessments carried out in different stages of the breeding season, between which detectability of individuals differed significantly. We believe this is the first time that a biodiversity monitoring method has been demonstrated to produce consistent abundance indices for a highly diverse avian tropical assemblage. We also suggest that the MacKinnon lists methodology has the potential to be a very useful conservation monitoring tool for many taxa in species rich environments, such as the tropics. © 2010 Elsevier Ltd. Source

Soria-Auza R.W.,Biodiversity Inc. | Kessler M.,University of Zurich | Bach K.,University of Marburg | Barajas-Barbosa P.M.,Biodiversity Inc. | And 4 more authors.
Ecological Modelling

The quality of climate models has largely been overlooked as a possible source of uncertainty that may affect the outcomes of species distribution models, especially in the tropics, where comparatively few climatic stations are available. We compared the geographical discrepancies and potential conservation implications of using two different climate models (Saga and Worldclim) in combination with the species modelling approach Maxent in Bolivia. We estimated ranges of selected bird and fern species biogeographically restricted to either humid montane forest of the northern Bolivian Andes or seasonal dry tropical forests (in the Andes and southern lowlands). Saga and Worldclim predicted roughly similar climate patterns of temperature that were significantly correlated. Precipitation layers of both climate models were also roughly similar, but showed important differences. Species ranges estimated with Worldclim and Saga likewise produced different results. Ranges of species endemic to humid montane forests estimated with Saga had higher AUC (Area under the curve) values than those estimated with Worldclim, which for example predicted the occurrence of humid montane forest bird species near Lake Titicaca, an area that is clearly unsuitable for these species. Likewise, Worldclim overpredicted the occurrence of fern and bird species in the lowlands of the Chapare region and well south of the Andean Elbow, where more seasonal biomes occur. By contrast, Saga predictions were coherent with the known distribution of humid montane forests in the northern Bolivian Andes. Estimated ranges of species endemic to seasonal dry tropical forests predicted with Saga and Worldclim were not statistically different in most cases. However, detailed comparisons revealed that Saga was able to distinguish fragments of seasonal dry tropical forests in rain-shadow valleys of the northern Bolivian Andes, whereas Worldclim was not. These differences highlight the neglected influence of climate layers on modelling results and the importance of using the most accurate climate data available when modelling species distributions. © 2010 Elsevier B.V. All rights reserved. Source

Pyritz L.W.,Behavioral Ecology and Sociobiology Unit | Buntge A.B.S.,Max Planck Institute for Evolutionary Biology | Herzog S.K.,Asociacion Armonia BirdLife International | Kessler M.,University of Zurich
International Journal of Primatology

Habitat structure and anthropogenic disturbance are known to affect primate diversity and abundance. However, researchers have focused on lowland rain forests, whereas endangered deciduous forests have been neglected. We aimed to investigate the relationships between primate diversity and abundance and habitat parameters in 10 deciduous forest fragments southeast of Santa Cruz, Bolivia. We obtained primate data via line-transect surveys and visual and acoustic observations. In addition, we assessed the vegetation structure (canopy height, understory density), size, isolation time, and surrounding forest area of the fragments. We interpreted our results in the context of the historical distribution data for primates in the area before fragmentation and interviews with local people. We detected 5 of the 8 historically observed primate species: Alouatta caraya, Aotus azarae boliviensis, Callithrix melanura, Callicebus donacophilus, and Cebus libidinosus juruanus. Total species number and detection rates decreased with understory density. Detection rates also negatively correlated with forest areas in the surroundings of a fragment, which may be due to variables not assessed, i.e., fragment shape, distance to nearest town. Observations for Alouatta and Aotus were too few to conduct further statistics. Cebus and Callicebus were present in 90% and 70% of the sites, respectively, and their density did not correlate with any of the habitat variables assessed, signaling high ecological plasticity and adaptability to anthropogenic impact in these species. Detections of Callithrix were higher in areas with low forest strata. Our study provides baseline data for future fragmentation studies in Neotropical dry deciduous forests and sets a base for specific conservation measures. © 2010 The Author(s). Source

Martinez O.,Higher University of San Andres | Oswaldo Maillard Z.,Gabriel Rene Moreno Autonomous University | Vedia-Kennedy J.,Servicio Nacional de Areas Protegidas SERNAP | Herrera M.,Asociacion Armonia BirdLife International | And 2 more authors.

We studied the avifauna of 11 localities of the Serranía del Aguaragüe National Park and Natural Area of Integrated Management, Gran Chaco Province, Tarija Department, Bolivia. A total of 272 species were recorded, 6 of which were threatened (Buteogallus coronatus, Ara militaris, Amazona tucumana, Vultur gryphus y Buteogallus solitarius). This study includes 11 new species records for Tarija Department and 14 that were previously known by a few records. Twenty-nine species were zoogeographical endemisms: 20 for Central South America region and 9 for Central Andes region. The Serranía del Aguaragüe National Park and Natural Area of Integrated Management is an important area with convergent avifaunistic elements belonging to western mountain forests and eastern Chaco, along with several migrant species, especially austral ones. Source

Gastanaga M.,Asociacion Armonia BirdLife International | MacLeod R.,University of Glasgow | Hennessey B.,Asociacion Armonia BirdLife International | Puse E.,Asociacion Armonia BirdLife International | And 5 more authors.
Bird Conservation International

During a period of 12 months in 2007 and 2008, a study of the parrot trade within Peru was carried out. In this study, 20 main wildlife markets were visited in eight cities in order to estimate the number of parrot species and individuals traded legally and illegally within a year. The study also gathered extra information from vendors and customers through informal interviews about the trade process. Additionally we contracted one person in two markets between February and May 2008 to monitor how many species and individuals entered the trade. During the study, four threatened species (the Endangered Gray-cheeked Parakeet Brotogeris pyrrhoptera, the Vulnerable Military Macaw Ara militaris, the Vulnerable Yellow-faced Parrotlet Forpus xanthops and the Near Threatened Red-masked Parakeet Aratinga erythrogenys) and one additional species listed in CITES Appendix 1 (Scarlet Macaw Ara macao) were found being traded. Thirty-four species were recorded in total, 33 of which are native to Peru (representing 63% of the 52 known Peruvian parrot species) and one of which (Monk Parakeet Myiopsitta monachus) is native to Bolivia and Argentina. Our results show that even for the seven species which can be legally traded in Peru, the number of individuals being traded can greatly exceed the numbers that can officially be traded legally. We directly counted 4,722 parrots for sale and using a measured detection rate of 3% we estimate a total market size in the cities surveyed of between 80,000 and 90,000 individuals. As our surveys sampled only 8 out of Peru's 24 departmental capitals and there are also other large cities, these numbers are likely to represent only a part of the total trade in Peru. To the best of our knowledge this is one of the first detailed studies of the internal trade in a source country for the international parrot trade. Our results suggest that such internal trade is likely to be a significant conservation issue that has previously been largely overlooked. © 2010 BirdLife International. Source

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