Distribution patterns, population status and conservation of Melanosuchus niger and Caiman yacare (Crocodylia, Alligatoridae) in oxbow lakes of the Ichilo river floodplain, Bolivia
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| Formato: | Online |
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Universidad de Costa Rica
2008
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| Acceso en línea: | https://revistas.ucr.ac.cr/index.php/rbt/article/view/5633 |
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RBT56332022-06-06T18:22:59Z Distribution patterns, population status and conservation of Melanosuchus niger and Caiman yacare (Crocodylia, Alligatoridae) in oxbow lakes of the Ichilo river floodplain, Bolivia Distribution patterns, population status and conservation of Melanosuchus niger and Caiman yacare (Crocodylia, Alligatoridae) in oxbow lakes of the Ichilo river floodplain, Bolivia Aguilera, Ximena S. Coronel, Jorge Oberdorff, Thierry A. Van Damme, Paul Amazona boliviana caiman yacaré planos de inundación Melanosuchus niger Bolivian Amazon Caiman yacare floodplain lakes Caiman yacare (lagarto) and Melanosuchus niger (black caiman), sympatric species in the Bolivian Amazon basin, have been severely overexploited in the past. We present the results of a standardized survey of C. yacare and M. niger populations in order to evaluate their actual population status in twelve oxbow lakes of the Ichilo River floodplain. Additionally we explored the effect of environmental and anthropogenic variables on caiman distribution patterns. The average density of C. yacare and M. niger in the shoreline of floodplain lakes was of 6 and 1 ind/km, respectively. For both species, the population was composed mainly of juvenile individuals. We used regression tree analysis (RTA) to assess patterns of M. niger and C. yacare densities with eight environmental and two anthropogenic variables. The RTA analysis showed that the variation in the densities of both C. yacare (52.4 %) and M. niger (36.8 %) was related to water conductivity. For C. yacare, higher densities occurred at higher values of water conductivity, while M. niger densities followed an opposite trend, resulting in relatively well spatially segregated populations of the two species. After excluding conductivity, Lake-River Distance (LRD) was shown to be the main splitting variable in the RTA analysis. The observed distribution patterns may be the result of the historical post-hunting situation, in combination with differences in habitat selection by the two species, and competitive exclusion processes between the two species. M. niger, a species reported to be recovering slowly from previous low population levels, appears relatively well protected in the Ichilo river floodplain. Universidad de Costa Rica 2008-06-01 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Article Text application/pdf https://revistas.ucr.ac.cr/index.php/rbt/article/view/5633 10.15517/rbt.v56i2.5633 Revista de Biología Tropical; Vol. 56 No. 2 (2008): Volume 56 – Regular number 2 – June 2008; 909–929 Revista de Biología Tropical; Vol. 56 Núm. 2 (2008): Volumen 56 – Número regular 2 – Junio 2008; 909–929 Revista Biología Tropical; Vol. 56 N.º 2 (2008): Volume 56 – Regular number 2 – June 2008; 909–929 2215-2075 0034-7744 10.15517/rbt.v56i2 eng https://revistas.ucr.ac.cr/index.php/rbt/article/view/5633/5377 Copyright (c) 2008 Revista de Biología Tropical http://creativecommons.org/licenses/by/4.0 |
| institution |
Universidad de Costa Rica |
| collection |
Revista de Biología Tropical |
| language |
eng |
| format |
Online |
| author |
Aguilera, Ximena S. Coronel, Jorge Oberdorff, Thierry A. Van Damme, Paul |
| spellingShingle |
Aguilera, Ximena S. Coronel, Jorge Oberdorff, Thierry A. Van Damme, Paul Distribution patterns, population status and conservation of Melanosuchus niger and Caiman yacare (Crocodylia, Alligatoridae) in oxbow lakes of the Ichilo river floodplain, Bolivia |
| author_facet |
Aguilera, Ximena S. Coronel, Jorge Oberdorff, Thierry A. Van Damme, Paul |
| author_sort |
Aguilera, Ximena |
| title |
Distribution patterns, population status and conservation of Melanosuchus niger and Caiman yacare (Crocodylia, Alligatoridae) in oxbow lakes of the Ichilo river floodplain, Bolivia |
| title_short |
Distribution patterns, population status and conservation of Melanosuchus niger and Caiman yacare (Crocodylia, Alligatoridae) in oxbow lakes of the Ichilo river floodplain, Bolivia |
| title_full |
Distribution patterns, population status and conservation of Melanosuchus niger and Caiman yacare (Crocodylia, Alligatoridae) in oxbow lakes of the Ichilo river floodplain, Bolivia |
| title_fullStr |
Distribution patterns, population status and conservation of Melanosuchus niger and Caiman yacare (Crocodylia, Alligatoridae) in oxbow lakes of the Ichilo river floodplain, Bolivia |
| title_full_unstemmed |
Distribution patterns, population status and conservation of Melanosuchus niger and Caiman yacare (Crocodylia, Alligatoridae) in oxbow lakes of the Ichilo river floodplain, Bolivia |
| title_sort |
distribution patterns, population status and conservation of melanosuchus niger and caiman yacare (crocodylia, alligatoridae) in oxbow lakes of the ichilo river floodplain, bolivia |
| title_alt |
Distribution patterns, population status and conservation of Melanosuchus niger and Caiman yacare (Crocodylia, Alligatoridae) in oxbow lakes of the Ichilo river floodplain, Bolivia |
| publisher |
Universidad de Costa Rica |
| publishDate |
2008 |
| url |
https://revistas.ucr.ac.cr/index.php/rbt/article/view/5633 |
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