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An initial inventory of the dolphins and whales occurring in Guinea's coastal waters is documented primarily from specimens and photographic evidence obtained from strandings and by-catches. Seven species are fully validated, four odontocetes, Tursiops truncatus, Sousa teuszii, Stenella frontalis, Kogia breviceps and three balaenopterid whales: Balaenoptera brydei, Balaenoptera acutorostrata and Megaptera novaeangliae. Another three reported species (Globicephala macrorhynchus, Steno bredanensis and Delphinus delphis) are insufficiently supported but thought to be valid. Small cetaceans landed as by-catch and a stranded whale were used for human consumption, but no evidence of substantial takes, directed or by-catch, was found. However, concern is raised about even minimal takes of the vulnerable Atlantic humpback dolphin. The seasonal presence of three confirmed humpback whales, two strandings (July and September) and a sighting (October), is synchronous with the species' southern hemisphere wintering/breeding season in low latitudes. We hypothesize that these whales may comprise the north-westernmost range of the population that breeds/overwinters in coastal waters of the Bight of Benin, northern Gulf of Guinea. [ABSTRACT FROM AUTHOR]

In January 2011, a group of 11 Indo-Pacific common dolphins Delphinus capensis tropicalis stranded in the central estuary of Bandar-e-Jask in Hormozgan Province (near the entrance to the Persian Gulf), Iran. All of them were females and just one is believed to have survived. Two individuals were pregnant. All carcasses were examined for biometry and genetic samples were obtained for subsequent analysis. They all appeared to have been in a good state of health prior to death without any signs of human-related injuries. A comprehensive investigation into the possible causes for mortality could not be conducted. However, the available evidence suggests that the most likely reason for the stranding was the complex topographic and oceanographic conditions, which may have caused the animals to be trapped by the rapidly falling spring tide. [ABSTRACT FROM PUBLISHER]

We document the composition by sex and size of 105 long-beaked common dolphins (57 males and 48 females) from a die-off in January–February 1995 in the upper Gulf of California, Mexico. Total length of males ranged from 191.2–264.7 cm and those of females ranged from 170.0–252.4 cm. These are the largest Delphinus reported to date anywhere in the world. [ABSTRACT FROM AUTHOR]

While short-beaked common dolphins are often regarded as highly mobile animals, their movements and ranging patterns are poorly known and no long-distance movements have been documented through photo-identification of individuals. We report the long-distance movement of a naturally marked individual, encompassing a minimum of 1000 km across the Ionian and the Adriatic Seas, and the subsequent behaviour and site fidelity of the same individual, in association with a calf, in and around the commercial port of Monfalcone, northern Adriatic Sea. This is the longest documented movement for any individual of this species, worldwide. [ABSTRACT FROM AUTHOR]

The taxonomy and distribution patterns of the common dolphins (genus Delphinus) are problematic among cetaceans and particularly complicated in the south-western Atlantic Ocean. On the basis of national collections, we found ten adult skulls of the genus Delphinus of Uruguayan origin. The two currently recognized species for the genus were identified based on craniometric measurements: the pelagic short beaked form (Delphinus delphis, N = 3) and the coastal long beaked form (Delphinus capensis, N = 4), although previous studies only recognized D. capensis for Uruguay. Three specimens could not be identified (Delphinus sp.) because of broken skull (2) and intermediate measures (1). This result is consistent with a recent review on the biogeography of the genus in the south-western Atlantic Ocean. [ABSTRACT FROM AUTHOR]