Modeling the Distribution of the Ota’s Bent-toed Gecko (Cyrtodactylus otai)
Main Article Content
Abstract
The Ota’s bent-toed gecko (Cyrtodactylus otai) was discovered in isolated karst outcrops of Hang Kia Commune, Mai Chau District, Hoa Binh Province, in 2015 and in Chieng Yen Commune, Van Ho District, Son La Province in 2017, in northwestern Vietnam. This gecko is both an endemic and endangered species of Vietnam, and its known range to date is restricted to a severely fragmented and small regions. Hence, to identify more populations and to better understand the distribution patterns of this cryptic species, we conducted field surveys in surrounding regions of the type localities from 2020 to 2023. We discovered eight new populations for C. otai, and expanded the known range of the species in Van Ho District (Son La Province) and Mai Chau District (Hoa Binh Province). We used species occurrence data from previous studies and our field surveys to model the gecko’s distribution using MaxEnt. The model results showed that the distribution of C. otai may include other nature reserves in surrounding regions, such as Pu Hu and Pu Luong (Thanh Hoa), and Ngoc Son – Ngo Luong (Hoa Binh). Based on the model results, there is a possibility that the Ota’s bent-toed gecko also occur in nearby Lao regions. Therefore, future research and conservation initiatives may focus their efforts in such areas to look for new populations of the Ota’s bent-toed gecko, as well as to assess the distribution, habitat, and ecological patterns of this poorly known reptile.
Keywords:
Cyrtodactylus otai, MaxEnt, Species Distribution Modeling.
References
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[11] J. Elith, S. J. Phillips, T. Hastie, M. Dudík, Y. E. Chee, C. J. Yates, A Statistical Explanation of Maxent for Ecologists, Diversity and Distributions, Vol. 17, No. 1, 2011. pp. 43-57, https://doi.org/10.1111/j.14724642.2010.00725.x.
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https://doi.org/10.1111/j.13652699.2010.02290.x.
[19] J. Elith, M. Kearney, S. Phillips, The Art of Modelling Range-Shifting Species, Methods in Ecology and Evolution, Vol. 1, No. 4, 2010,
pp. 330-342, https://doi.org/10.1111/j.2041210x.2010.00036.x.
[20] R. G. Pearson, C. J. Raxworthy, M. Nakamura, A. T. Peterson, Predicting Species Distributions from Small Numbers of Occurrence Records: A Test Case Using Cryptic Geckos in Madagascar, Journal of Biogeography, Vol. 34, No. 1, 2007, pp. 102-117, https://doi.org/10.1111/j.13652699.2006.01594.x.
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Vol. 21, No. 2, 2011, pp. 335-342, https://doi.org/10.1890/10-1171.1.
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[24] T. N. Van, B. Rawson, C. Hallam, M. Kenyon, T. Nadler, L. Walter, C. Roos, Phylogeny and Distribution of Crested Gibbons (Genus Nomascus) Based on Mitochondrial Cytochrome B Gene Sequence Data, American Journal of Primatology, Vol. 72, No. 12, 2010, pp. 1047-1054, https://doi.org/10.1002/ajp.20861.
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