The Raffles Bulletin of Zoology (2002)


This study provides information on food habits and insights into habitat use of finless porpoises (Neophocaena phocaenoides) in Hong Kong waters through the analysis of stomach contents of 31 stranded animals. Finless porpoises preyed upon a minimum of 25 species of fish, 3 genera of cephalopods and one shrimp. The most important prey taxa in numerical terms were the fish families Apogonidae, Sciaenidae, Engraulidae, Leiognathidae among teleosts, and the squid family Loliginidae. Squids (Loligo) and cuttlefishes (Sepia), followed by anchovies (Thryssa spp.), cardinalfishes (Apogon spp.) and ponyfishes (Gazza minuta) were the most frequently taken prey. These are inshore, bottom-dwelling and mid-water prey, suggesting that finless porpoises feed at different levels in the water column and in reefs and sandy substrates. Prey composition and the presence of undigested fish, squid and shrimp retrieved from several porpoise stomachs suggest possible associations with fisheries, particularly trawlers. Onset of ingestion of solid food takes place at 6-12 mos. (95-100 cm in size). No sex-related or seasonal differences in diet were round. There was some dietary overlap with humpback dolphins, but these animals appear to favour prey species common in estuaries, whereas finless porpoises also exploit more pelagic habitats for food. Prey overlap is greater with offshore bottlenose dolphins, suggesting some competition when these dolphins venture into coastal waters.