Changes in the population of structure of the spectacled caiman, Caiman crocodilus (Crocodilia: Caimanidae) and its possible relation with climate change, in Caño Negro, Costa Rica

Changes in the population of structure of the spectacled caiman, Caiman crocodilus (Crocodilia: Caimanidae) and its possible relation with climate change, in Caño Negro, Costa Rica

Authors

  • J Manuel Aranda-Coello Instituto Internacional en Conservación y Manejo de Vida Silvestre, Universidad Nacional, Heredia, Costa Rica

DOI:

https://doi.org/10.22458/urj.v9i1.1691

Keywords:

Caymans, conservation, crocodylians, wildlife manage¬ment, sex ratio.

Abstract

The spectacled caiman, Caiman crocodilus, is ecologically and economi­caly important in some areas of Latin America. In Costa Rica it is not abundant and there is a need for population data. I studied it in Caño Negro National Wildlife Refuge, Costa Rica, through the collection and comparison of previous studies and the incorporation of recent infor­mation. I made night boat trips with a 2 million lumen lamp (400m spec­trum) and manually captured individuals under 60cm long. For larger sizes or animals located in areas of difficult access, I used Thompson ties and 2m long poles with an inserted rope, and captured 180 caiman. Most were sub-adults and there were 1:12 females per male, unusually high for the species and possibly caused by environmental conditions. The efects of global warming could disrupt the sex ratio and reproduc­tive structure of spectacled caimans.

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Published

2017-03-14

How to Cite

Aranda-Coello, J. M. (2017). Changes in the population of structure of the spectacled caiman, Caiman crocodilus (Crocodilia: Caimanidae) and its possible relation with climate change, in Caño Negro, Costa Rica. UNED Research Journal, 9(1), 151–155. https://doi.org/10.22458/urj.v9i1.1691

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