Occurrence of Hector's beaked whale, Mesoplodon hectori, in southern Brazil

Abstract

In February 1994, a Hector’s beaked whale, Mesoplodon hectori, was found ashore 80 km north of Rio Grande (32)07*S, 52)05*W), southern Brazil.The skull (CBL=497 mm) and post-cranial skeleton(C 7, T 11, L 10, Ca 17=45) were collected and placed at the Museu Oceanogra´fico ’Prof. Eliézer de Carvalho Rios’ collection (MORG 0104). The whale was identified based on skull morphology and measurements, as well as shape and position of the mandibular teeth. The small size (skeletal length=236 cm), unfilled mesorostral channel, wide open tooth pulp cavity, and unfused vertebral epyphisis indicated that the animal was young. This whale is the first record of the species in Brazil. In addition, it extends northwards the known range of Hector’s beaked whale in the west South Atlantic Ocean by about 800 km and represents the northernmost record of the species.