Mercury concentrations and trophic relations in sharks of the Pacific Ocean of Colombia.

Sharks are fished for human consumption in Colombia, and fins are exported illegally to international markets. The goal was to identify differences in total mercury (THg) concentrations in fins and muscles of shark species seized in the Buenaventura port (Colombian Pacific), and to assess potential human health risks related to shark consumption. Seven species were considered in this study: Pelagic Thresher (Alopias pelagicus), Pacific Smalltail Shark (Carcharhinus cerdale), Brown Smoothhound (Mustelus henlei), Sicklefin Smoothhound (Mustelus lunulatus), Scalloped Bonnethead (Sphyrna corona), Scalloped Hammerhead (Sphyrna lewini), and Bonnethead Shark (Sphyrna tiburo), and THg was analyzed in shark tissues.

Seascape Genetics of the Atlantic Spotted Dolphin (Stenella frontalis) Based on Mitochondrial DNA.

The Atlantic spotted dolphin (Stenella frontalis) is endemic to tropical, subtropical, and warm temperate waters of the Atlantic Ocean. Throughout its distribution, both geographic distance and environmental variation may contribute to population structure of the species. In this study, we follow a seascape genetics approach to investigate population differentiation of Atlantic spotted dolphins based on a large worldwide dataset and the relationship with marine environmental variables.

Phylogeography, genetic diversity and population structure of the freshwater stingray, (Müller & Henle, 1841) (Myliobatiformes: Potamotrygonidae) in the Colombian Amazon and Orinoco basins.

The freshwater stingray have coloration, osteological and morphometric variations that could suggest the existence of more than one species in Colombia. In order to evaluate the phylogeography, population structure and genetic diversity for distributed in the Amazon and Orinoco basins, we amplified partial region of mitochondrial DNA () in 50 samples from eight different sub-basins. Our results suggest three phylogroups and a vicariance event occurred 43 million years ago proposing how diverged into the basins.

High genetic structure and low mitochondrial diversity in bottlenose dolphins of the Archipelago of Bocas del Toro, Panama: A population at risk?

The current conservation status of the bottlenose dolphin (Tursiops truncatus) under the IUCN is 'least concern'. However, in the Caribbean, small and localized populations of the 'inshore form' may be at higher risk of extinction than the 'worldwide distributed form' due to a combination of factors including small population size, high site fidelity, genetic isolation, and range overlap with human activities. Here, we study the population genetic structure of bottlenose dolphins from the Archipelago of Bocas del Toro in Panama.

Range extension for the common dolphin (Delphinus sp.) to the Colombian Caribbean, with taxonomic implications from genetic barcoding and phylogenetic analyses.

The nearest known population of common dolphins (Delphinus sp.) to the Colombian Caribbean occurs in a fairly restricted range in eastern Venezuela. These dolphins have not been previously reported in the Colombian Caribbean, likely because of a lack of study of the local cetacean fauna.