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.

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HKU Student Identifies Dinosaur-Era Fish in Sai Kung Rocks

A Hong Kong University (HKU) student is said to have identified a Jurassic fish from Lai Chi Chong after studying some fossil collections at the university’s Stephen Hui Geological Museum.

Edison Tse Tze-kei found the specimen by chance as he was doing a research project in his final year of undergraduate study during the 2013-14 academic year, according to an announcement from HKU.

The fish, which is believed to date back to around 147 million years, represents the first dinosaur-era vertebrate specimen identified in Hong Kong, the university said in a statement posted on its website Thursday.

   

 

Tse, a graduate of the class of 2014, completed the research, description and identification under the supervision of three professors, including Michael Pittman, Research Assistant Professor and Head of the Vertebrate Palaeontology Laboratory at HKU.

The research results will now be published in PeerJ, an open access, peer-reviewed, scholarly journal of biological and medical sciences, by the end of this month.

The fossil specimen was found at Lai Chi Chong in Sai Kung, which is within the Hong Kong Geopark area, and was kept at a HKU museum.

The Jurassic fish was an osteoglossoid teleost fish, which is also referred to as Paralycoptera.

 

The preserved skeleton represents the first of such fish species from Hong Kong and the most southerly Paralycoptera identified to date, meaning that the activity area of the fish could be larger than scientists had first estimated.

Matthew Sin, a spokesperson for local NGO Green Power, said some visitors to Lai Chi Chong may have taken away rocks as souvenirs.

He reminded people that taking any sedimentary rocks, fossil, mineral or even sand samples from the Geopark is illegal.

Featured image: Magnified image (inset) of a fossil specimen from a Lai Chi Chong geological collection. Research by a HKU student has led to Hong Kong’s first identified dinosaur-era vertebrate. Credit:10.7717/peerj.865

3rd Dead Dolphin of 2015 Found Near the Airport

A team from the Ocean Park Conservation Foundation (OPCF) yesterday (24/3/2015) examined the dead body of a Chinese white dolphin found in waters near the Hong Kong airport.

The carcass was first spotted floating off of the Brothers, a pair of islands to the northeast of the Hong Kong International Airport.

The team was unable to determine the cause of death since the body was severely decomposed, but samples were collected for further study.

“Unfortunately, we can only confirm the cause of death in less than 10 percent of cases, mainly because most of the carcasses are badly decomposed when discovered,” said Shadow Sin, the assistant manager of scientific projects for OPCF.

  

It’s the third cetacean stranding case reported so far this year. This month also so the death of the injured dolphin nick-named ‘Hope’.

Hong Kong’s Chinese white dolphins, widely known as pink dolphins, are threatened by habitat loss and marine traffic.

The range of pink dolphins in Hong Kong has shrunk substantially since the construction of the Hong Kong International Airport at Chek Lap Kok.

If you spot a dead or distressed animal you should immediately call the Hong Kong government hotline at 1823. 

Images by Ocean Park Conservation Foundation