Description of the first acoustic recording of spinner dolphins (Stenella longirostris) from the northern straits of Malacca, Malaysia (L)

Relatively little is known about spinner dolphins in Malaysian waters and the wider Southeast Asian region. This note represents the first known acoustic recording of the species sighted opportunistically in the northern Straits of Malacca. Over a brief 20 min sighting, 46 whistles were recorded and four tonal types were detected, with 54.4% being upsweep whistles. The whistle duration ranged from 36 to 977 ms and the frequency ranged from 6.6 to 23.8 kHz. Fifty-seven click trains with a mean interclick interval of 41.5 ± 19.3 ms were detected. These findings provide a baseline for future regional acoustic research on this species.