During 1995, 2001, 2003, 2004 and 2007; we studied the temporal variation in the structure of the elasmobranch assemblage along the Colombian Pacific coast using: the community index of diversity, heterogeneity, equitability, species composition, average catch sizes, and mean trophic levels. A total...

Full description

Autores:
Navia, Andrés Felipe; Fundación colombiana para la investigación y conservación de tiburones y rayas SQUALUS
Mejía-Falla, Paola Andrea; Fundación colombiana para la investigación y conservación de tiburones y rayas SQUALUS
Tipo de recurso:
Article of journal
Fecha de publicación:
2016
Institución:
Pontificia Universidad Javeriana
Repositorio:
Repositorio Universidad Javeriana
Idioma:
eng
OAI Identifier:
oai:repository.javeriana.edu.co:10554/31951
Acceso en línea:
http://revistas.javeriana.edu.co/index.php/scientarium/article/view/15344
http://hdl.handle.net/10554/31951
Palabra clave:
null
sharks; rays; fisheries; trophic levels; community structure
null
Rights
openAccess
License
Atribución-NoComercial-SinDerivadas 4.0 Internacional
Description
Summary:During 1995, 2001, 2003, 2004 and 2007; we studied the temporal variation in the structure of the elasmobranch assemblage along the Colombian Pacific coast using: the community index of diversity, heterogeneity, equitability, species composition, average catch sizes, and mean trophic levels. A total of 1711 specimens from 19 species (7 sharks and 12 rays) were collected during the 90 trawling operations. The number of species captured varied between 7 (1995) and 12 (2007) demonstrating a trend towards an imbalance in the assemblage attributes. In 1995, the mean trophic level (TLm) of the assemblage was 3.60, but in 2007 it decreased to 3.55 when the functional level of large predators was absent (TL ≥ 4). These results suggest changes in species composition, structural attributes, and a reduction of the highest functional level. Alterations to the catch proportions were also found: i.e. a greater abundance of rays of lower trophic levels. This study suggests an effect of trawling on the stability of this tropical coastal ecosystem.