Tell-tale signs of the intruder's species

PUBLISHED : Sunday, 09 September, 2001, 12:00am
UPDATED : Sunday, 09 September, 2001, 12:00am

LIFEGUARDS INITIALLY told Stanley Fisherman's Association that the marine mammal that made its way through the net was a Whaleshark. Whalesharks are actually the largest species of fish, growing up to 15 metres in length and weighing 20 tonnes. Though their appearance may be intimidating, they are harmless to humans, feeding on microscopic prey such as plankton and algae, as well as small crustaceans, fish, and squid.

'Whalesharks have been very common this year,' says Keith Wilson, a senior officer with the Agriculture, Fisheries and Conservation Department. 'They're certainly not unusual in Hong Kong.'

Tony Lai Kam-hung, president of the Stanley Fisherman's Association, says that 20 years ago, Whalesharks sometimes visited the waters just off the peninsula where Stanley Prison is situated. But details later surfaced that strongly suggested the creature which appeared at St Stephen's Beach was a finless porpoise. Whalesharks are brown and have a distinct pattern. But the creature in question was dark grey to black, according to lifeguard accounts and that of bather Hau Man-ping.

More telling, according to witnesses, the creature had no fin, but did have a blowhole. While there's a remote chance a Whaleshark could have been finned by fishermen and sought out shallow water as it breathed its dying breaths, the species does not have a blowhole. If it had no fin and a blowhole, it was probably a finless porpoise, so named because it lacks a dorsal fin. Also fitting the profile, finless porpoises range in colour from grey to black and are known to inhabit the waters around Stanley, says Mr Wilson.

Problem is, a finless porpoise is even smaller than the Chinese White Dolphin, or Pink Dolphin as they are known. Some witnesses insist the creature was much larger. Such proportions point to a whale, the likely suspect being a Bryde's Whale. '[In Hong Kong waters] they're common by whale standards,' says Mr Wilson, but are rarely sighted.

Bryde's Whales, however, have twin blowholes and three distinct longitudinal ridges on their heads - features not mentioned by the witnesses.

Whatever appeared at Stanley certainly sparked fears of a shark attack - and left others wondering what would be the next big fish to get through a damaged net.