Category Archives: Rays

The Stingrays of Hong Kong

I have just added a page about all the different species of ray that are found in Hong Kong. Here is a little preview on just the stingrays. Check out the full list of rays here.

The Stingrays of Hong Kong:

 

Round ribbontail Ray / Black-spotted stingray (Taeniura meyeni)

Round Ribbontail Ray (via WikiCommons)
Round Ribbontail Ray (via WikiCommons)
A bottom-dwelling inhabitant of lagoons, estuaries, and reefs, generally at a depth of 20–60 m (66–197 ft). Reaching 1.8 m (5.9 ft) across. Generally nocturnal, the round ribbontail ray can be solitary or gregarious, and is an active predator of small, benthic molluscs, crustaceans, and bony fishes. Although not aggressive, if provoked the round ribbontail ray will defend itself with its venomous tail spine. In Hong Kong, it is found mainly in the relatively clear southern and eastern waters, but it has also been found in the northern part of Lantau and in brackish water near the Pearl River estuary. It is also one of the species that has been found on Hong Kong’s artificial reefs. Check out Eric Keung’s spooky photo of a this stingray in Hong Kong waters.
Between July 2005 and June 2008 there were two cases of people being stung by stingrays in HK – fortunately with mild outcomes. The sting and its venom can cause bluish or greyish discoloration around the wound, disproportionate pain, muscle cramp, weakness, seizure, hypotension, cardiovascular toxicity, deep wounds and lacerations. In other words, stingrays are dangerous! Just watch from a distance and don’t touch!


Blue-Spotted Stingray (Neotrygon kuhlii)

Blue-Spotted Stingray, Papua New Guinea (via WikiCommons)
Blue-Spotted Stingray, Papua New Guinea (via WikiCommons)
The body is rhomboidal and green with blue spots with a maximum width estimated at 46.5 centimeters (18.3 in). The rays coloration is a warning for the highly poisonous barbs, thus few animals attempt to overpower this ray. In HK, they are more easily seen in summer in the shallow water along the coast, on coral reefs and in mangrove areas. Because of the venomous sting observers should not get too close or try to touch it!


Pale-edged stingray (Dasyatis zugei)

Pale-edged Stingray (via WikiCommons)
Pale-edged Stingray (via WikiCommons)
A bottom-dwelling ray most commonly found over sandy areas shallower than 100 m (330 ft) and in estuaries. It measures up to 29 cm (11 in) across, has a diamond-shaped pectoral fin disc, a long projecting snout, small eyes, and a whip-like tail. It is chocolate-brown above and white below and feeds mainly on small crustaceans and fishes. In HK it is mainly found in the western Pearl River estuary south of Lantau Island.

24th of June 1957 – 11-foot Manta Ray Caught Off Big Wave Bay

History and nature appreciation don’t normally go hand in hand, but they should, because unless you know what used to live in Hong Kong waters, you don’t know what constitutes ‘good condition’ of the marine environment. So I love looking through old papers and spotting the ‘monsters’ of long ago.

And here is one the China Mail reported on its front page on 24th of June 1957:

MANTA RAY CAUGHT AT BIG WAVE

Chinese fisherman caught a 11-foot (3.35 m) Manta ray at Big Wave Bay yesterday afternoon. This was reported this morning by a Colony resident, Mr A S Dower. Mr Dower said there were two junks lying off the beach an it appeared that the Manta was caught from one of these. At about 7.15 p.m. , as the beach began to clear, the fisherman rowed a sampan to shore towing the ray behind. Then they beached the ray. Mr Dower said that when he left soon after it was still there. The catching of the ray was the climax of an exciting afternoon. The shark bell sounded four or five times. “It seemed to be dinging all afternoon”, one swimmer said. “I am not sure they were all sharks. I saw a fin once a good way out but I’m not sure it was a shark or a Manta.The Manta has a small fin – I noticed it when it was brought to shore,” he said. Big Wave Bay was crowded yesterday afternoon. Two rows of tents lined the beach and during the afternoon they were fully occupied. But the surf was flat. A porpoise was also reported to have been caught at Big Wave Bay last night.

So, 3.35 m wide Manta rays and porpoises at Big Wave Bay in 1957. We still have the finless porpoise (Neophocaena phocaenoides) in HK, but I have never heard of anyone seeing or catching a Manta ray in my living memory. Nur according to other sources villagers in eastern waters caught manta rays in the 1960’s using the oil from the liver to light lamps and the gills as medicine. Manta rays are oceanic species and not really costal dwellers, so I suspect they would only pass through HK much like great whales, tuna and many shark in the summer months. According to the Agriculture, Fisheries and Conservation Department the species Manta birostris has been reported from HK waters and they can grow up to 8 m in width!

It’s my hope that someday some HK diver is going to post an amazing video online – like the one below from Bali (WikiCommons)- of Manta rays swimming through Hong Kong waters. And this is not an unrealistic hope either! The Thames river and estuary was delcared ‘biologically extinct’ in the 50’s but recovered following environmental protection legislation and efforts to rehabilitate it, and now it has dolphins, salmon, seals and even the occasional whale…right up to central London. And similar things have happened in other formerly polluted waterways near major cities. As long as we don’t cause species to go extinct (in the case of Mantas by eating too much of their gills and killing them as bycatch etc), there is always hope they will someday come back.