Fraser's dolphin (<i>Lagenodelphis hosei</i> Fraser, 1956) in southern Brazil
AbstractThe Fraser's dolphin, Lagenodelphis hosei Fraser, 1956, is distributed in tropical oceanic waters worldwide. There is little information on the biology and distribution of this species in the Southwestern Atlantic Ocean. From September to November 1997, 10 stranded Fraser's dolphins were collected along the northern Rio Grande do Sul coast, southern Brazil. The reproductive status was determined for seven animals; the sample was comprised mainly of sexually mature dolphins. Total length varied from 241.0 to 245.0cm for females and 216.0 to 258.0cm for males. Several fetal bones were found in the vaginal channel of one female. Analyses of stomach contents from six animals revealed remains of coastal species of cephalopods, fishes and crustaceans, suggesting that these dolphins were feeding nearshore prior to stranding. Five dolphins had large quantity of the parasite Phyllobotrium delphini (larval stage) in the blubber layer, particularly in the genital region. Although this species is considered to be tropical in distribution, the records from the Southwestern Atlantic are concentrated in temperate areas (30-35°S). Fraser's dolphin strandings in Rio Grande do Sul were not isolated events, and several other were recorded for the Brazilian, Uruguayan and Argentinean coast in the same and subsequent years. This may represent a complex phenomenon involving several causes, such as transient oceanographic events, diseases and other variables.
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).