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RESEARCH ARTICLE

Analysis of the population dynamics of the endangered American crocodile, Crocodylus acutus in Paramillo National Natural Park

Angela María Ortega-León https://orcid.org/0000-0003-2904-4077 A D , Amilcar H. Santos-Morales A B , Joan Gastón Zamora-Abrego B and Hibraim Adán Pérez-Mendoza C
+ Author Affiliations
- Author Affiliations

A Grupo de investigación Biodiversidad Unicórdoba, Facultad de Ciencias Básicas, Departamento de Biología, Universidad de Córdoba, Montería, CP 230003, Córdoba, Colombia.

B Grupo de investigación Ecología y Conservación de Fauna Silvestre, Facultad de Ciencias Agrarias, Departamento de Ciencias Forestales, Universidad Nacional de Colombia, Medellín CP 050034, Antioquia, Colombia.

C Laboratorio de Ecología Evolutiva de Anfibios y Reptiles, Facultad de Estudios Superiores Iztacala, UNAM, Avenida de Los Barrios Número 1, Los Reyes Iztacala, Tlalnepantla, Estado de México, CP 54090, México.

D Corresponding author. Email: angelamaria@correo.unicordoba.edu.co

Marine and Freshwater Research 72(1) 14-25 https://doi.org/10.1071/MF19026
Submitted: 3 September 2019  Accepted: 1 March 2020   Published: 23 April 2020

Abstract

Few studies have been conducted on the population dynamics of crocodiles, especially in the Neotropics. This is the first study to provide data on the population dynamics of the threatened American crocodile (Crocodylus acutus (Cuvier, 1807)) in Paramillo National Natural Park. Twenty-four survey routes of 22 km each were studied, and a total of 733 sightings was recorded. During the study period (from October 2014 to March 2016), the population remained stable and experienced slight growth (λ = 1.049 ± 0.428). Offspring production by the adults II stage was the most sensitive contribution (17.05), whereas the permanence of this adult stage was the demographic process that contributed the most to population growth (0.653). However, an 18% decrease in adults II would jeopardise long-term population viability and lead to a high probability of quasi-extinction, with under 300 individuals over the next 30 years. Thus, despite the apparent stability of this population, we suggest that it be considered a key target for future conservation efforts. Additionally, we recommend that this species continue to be listed as endangered in Colombia and not be modified in the CITES Appendix I.

Additional keywords: isolated population, River Manso, River Tigre, survival, URRA dam.


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