Grampus griseus (G. Cuvier, 1812) —Risso’s Dolphin, gray grampus

Delphinus griseus G. Cuvier, 1812 p.14; Type locality- Finistère, France.

Grampus sakamata Gray, 1846 p.31; Type locality- Japan.

G. stearnsii Dall, 1873 p.13; Type locality- coast of California, US.

G. griseous: Kuroda, 1938 p.18; Kim et al., 2000 p.92, 2004 p.241.

Range: The distribution of the species encompasses Korea, with most observations recorded in the East Sea, where continental shelves below a depth of 200 m provide breeding sites along the central coast from Gangneung to Sokcho (Cetacean Research Institute 2007; Fig. 92).

Remarks: Risso’s dolphin has a worldwide distribution, but little information exists about the genetic structure among local, coastal populations. Genetic data indicate low diversity between inshore and offshore populations with microsatellite DNA markers (F ST = 0.0296) and mtDNA sequences (F ST = 0.260). Gaspari et al. (2007) estimated low allelic diversity for nearly all loci among all populations. So far, Risso’s dolphin has been considered a monotypic species.