Records of Guiana dolphin, <i>Sotalia guianensis</i>, in the State of Ceará, Northeastern Brazil
AbstractThe Guiana dolphin, Sotalia guianensis, is a small delphinid found in costal waters, estuaries and bays from Santa Catarina, Brazil, to Nicaragua. Strandings of Guiana dolphins were recorded systematically and opportunistically in the coast of Ceará (~02-04°S), northeastern Brazil, from 1992 to 2005. A total of 160 single events were documented. The number of records was higher in Fortaleza Metropolitan Region than in other three surveyed areas, probably due to a more intensive survey effort. More strandings were recorded during austral winter and spring. The majority of stranded animals were adults (48.8%). Calves were not commonly recovered and no seasonality in the strandings of calves was observed. Overall body length ranged from 95 to 208cm for females and from 85 to 210cm for males. A total of 49 animals (30.6%) showed evidence of fishery interactions such as net marks and cuts. Of these, we confirmed through fisherman information the incidental catch of 13 dolphins by driftnet (n = 8), surface gillnet (n = 3) and beach seine (n = 2). Twenty three percent of all stranded animals showed evidences of other human interactions, like meat or fins removed, eyes removed and rostrum extracted. According to the results, Guiana dolphin strandings occurred year-round in all zones along the coast of Ceará. The incidental bycatch in fishing nets may have a negative impact on the dolphin population. The study reveals that a long-term systematic monitoring of artisanal fishing communities is necessary to evaluate the extent of the impact on the species.
LicenseAuthors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).