RESUMO
ABSTRACT Coral reefs inside Cartagena Bay have disappeared, largely due to the constant discharge of contaminated, sediment-rich freshwater from the Dique Channel. Recently, which might be the last healthy coral reef in the bay was found between Bocachica and Barú. Despite the unfavorable conditions for coral development, this reef exhibits an average coral cover of around 45 %. To study its fish diversity, inventories were made between 2015 and 2019, based on censuses during errant dives, band transects, photographs, and video recordings. A list of all fish species observed at Varadero reef, where 147 species belonging to 49 families have been recorded is presented; seven of those species (5%) are cataloged under threat. This study is the first approach to the fish diversity in this unusual reef, and a starting point for future studies that address the functionality and proper conservation of this ecosystem, currently threatened by projects that seek to dredge it.
RESUMEN Los arrecifes de coral dentro de la bahía de Cartagena han desaparecido, en gran parte debido a la constante descarga de agua dulce contaminada y rica en sedimentos del Canal del Dique. Recientemente, el que podría ser el último arrecife de coral saludable de la Bahía fue encontrado entre Bocachica y Barú. A pesar de las condiciones desfavorables para el desarrollo de los corales, este arrecife exhibe una cobertura de coral promedio de alrededor del 45 %. Para estudiar su diversidad de peces, se hicieron inventarios entre 2015 y 2019, basados en censos durante buceos errantes, transectos de bandas, fotografías y grabaciones de video. Se presenta una lista de todas las especies de peces observadas en el arrecife de Varadero, donde se han registrado 147 especies pertenecientes a 49 familias; siete de esas especies (5%) están catalogadas como amenazadas. Esta investigación es el primer acercamiento a la diversidad de peces en este inusual arrecife, y un punto de partida para futuros estudios que aborden su funcionalidad y adecuada conservación, actualmente amenazada por los proyectos que pretenden su dragado.
RESUMO
The morphological and genetic identification of hydrozoans collected in the reef patches of Santa Marta, Colombia was carried out. This study allows to present two new records of hydroids species for the Colombian Caribbean: Halopteris alternata and Dentitheca dendritica. A total of 11 species and 1 genus were found using morphological and genetic identification with partial sequences of the mitochondrial 16S rRNA gene. The order Leptothecata was the most abundant represented by 9 families: Aglaopheniidae, Clytiidae, Haleciidae, Halopterididae, Kirchenpaueriidae, Plumulariidae, Sertularellidae, Sertulariidae and Thyroscyphidae, while the order Anthoathecata was represented by 2 families: Eudendriidae and Pennariidae. Despite the lack of studies on this group of organisms in the country, the use of the 16S rRNA gene proved to be very useful to provide complementary evidence in our understanding of the biological diversity of hydrozoans in Colombia.