Records of killer whales (Orcinus orca) in Thai waters

Abstract

Killer whales (Orcinus orca) are found in all oceans and seas, in both hemispheres. Recent genetic, morphological, coloration and ecological evidences suggested that there are several geographic forms of killer whale i.e. Type A resident, Type A transient, Type B, Type C, and Type D. This paper provides killer whale records in Thailand since 1993 to 2008. There were 11 records of killer whale sightings in Thai waters; 10 records were from the Andaman Sea and 1 record was from the Gulf of Thailand. All sightings were from coastal areas of 3 provinces; Phang-nga, Phuket and Surat Thani and most of them were concessionary recorded by tourists. The sighted pods were around 2-30 individuals. Among all records, the photographs were available for type identification from 2 records in 2006-2007. The closed saddle patch that extends forward and the more pointed dorsal fin tip indicated that they were Type A transient killer whale. Additionally, killer whales in the Andaman Sea were reported to prey upon mantas.