Tag Archives: pearl river estuary

Rescued rare dolphin released back to sea

Xinhua reported on the 22nd of July (2017) that a rare rough-toothed dolphin (Steno bredanensis), named Jiangjiang, was released back to sea earlier this week, two months after it beached itself and was rescued in Guangdong Province.


The 2.2-meter male dolphin was found stranded on the coast of Heisha Bay near the city of Jiangmen (200 km west of Hong Kong) on May 3. It was suffering breathing troubles, according to Yang Naicai, a vet who joined the rescue operation.


Rescuers checked the dolphin’s breathing, gave an injection of antibiotics, and provided food and medicine to help it regain its strength.

The animal was housed in a pool designated for dolphin rescue at the Pearl River Estuary Chinese White Dolphin National Nature Reserve.


“We maintained round the clock monitoring, hoping for a miracle,” said Chen Hailiang, from the reserve.

The dolphin, which weighs around 100 kg, was released back to the sea on Thursday as its physical condition had returned to normal.

Although the rough-toothed dolphin, a national second class protected species, can be found in deep tropical, subtropical and temperate waters around the world, it is a rare visitor to Chinese coastal waters.

In 2014, a rough-toothed dolphin stranded in Guangdong died despite rescue efforts.

Chinese White Dolphin Stuck in Pearl River Tributary

Wildlife experts in south China are trying to rescue an endangered Chinese white dolphin (Sousa chinensis) that is in worsening health after swimming into a tributary of the Pearl river a week ago. The dolphin is approximately 30 years old and swam into the Baisha Rivernear Jiangmen in Guangdong Province on the 1st of February. It is now in a stretch of water about 100 km from the sea. “[…] the skin of the dolphin is festering and its health is deteriorating … its moving area is shrinking,” said Feng Kangkang, a worker with Jiangmen Chinese White Dolphin Nature Reserve, on Thursday. The team is watching the dolphin around-the-clock and recording its health condition, according to the Guangdong provincial ocean and fishery department. Dubbed the “giant pandas of the sea” by some, the Chinese white dolphins are mainly scattered in a few coastal areas where they exist in small numbers. About 2,000 are known from areas around the Pearl River, including HK which at the last count, was down to about 60 dolphins. (Photo/Xinhua)

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.

The Macau Whale Stranding Febuary 3rd, 1933

Sometimes it is very amusing and interesting to realize how different we see the environment now in 2015 compared to our attitudes the last century. A case in point is this gem of a news article from 1933 about a 25-foot (7.6 m) whale that stranded in Macau. Today, we would go to extraordinary efforts and spare no cost to rescue the whale and help it out to sea. Back in 1933 attitudes were a bit different, however…

“Much excitement was created in the little fishing hamlet of Tsam Mang Chin, not far from the Macao Barrier Gate, when a whale, 25 feet long, drifted ashore and was left high and dry on the beach when the tide went out.
The villagers were all activity, when the monster was sighted, and measures were promptly taken to prevent its escape. The whale was soon dragged higher up the beach, where it was killed, and operations to convert the oil and remains into cash were immediately carried out.

All day long, villagers from the surrounding country trooped into the hamlet to buy the whale oil and the flesh until nothing was left of the monster excepting the bones.

A fee was later charged for viewing the skeleton.

Some idea of the size of the whale may be gathered from the fact that a thousand catties [500 kg] of oil and twice the amount of flesh were sold by the captors.”

(Hong Kong Telegraph February 3rd, 1933)

These days, however, a “big whale” in Macau refers to big-ticket casino gamblers from mainland China. But with the anti-corruption campaign ongoing in China, the new “big whales” seem to be facing the same sort of steep decline that the real whales faced in the 20th century!

Huge, Critically Endangered Chinese Bahaba given as Father’s Day Present

A man has spared no expense on a ¥3million (£285,500) fish for his father-in-law.

The 50kg Chinese Bahaba (Bahaba taipingensis, Giant Croaker or黃唇魚 or 黄唇鱼) is 1.6m long and was caught as part of a local Dragon Boat Festival tradition in Fujian Province.

‘We’ve never seen such a big Bahaba in many years,’ said locals.

The fish is found on the coast of China, from the Yangtze River estuary southwards to the Pearl River estuary, including the waters of Hong Kong and Macau. It is a marine species that reaches lengths up to 2 metres (6 ft 7 in) and weights in excess of 100 kilograms (220 lb). Its natural habitats are shallow seas, subtidal aquatic beds, rocky shores, and estuarine waters. It enters estuaries to spawn and may be present there seasonally in large numbers. These include the Yangtze River, the Min River and the Pearl River and around the coast of Zhoushan Island (off the coast of Ningbo). It feeds mostly on shrimps and crabs.

It spawns in April and after spawning, the adults move out to deeper waters. Juveniles may be found in estuarine and coastal areas.

It is threatened by massive over fishing that continues despite legal protection in mainland China. Annual catches of fifty tonnes were taken in the 1930s but this had dwindled to 10 tonnes per year by the 1950s and 1960s by which time few large fish were caught. Despite legal protection in the mainland China, it is has no legal protection in Hong Kong, but it has been listed as critically endangered by the International Union for Conservation of Nature.  It is still caught and landed in mainland China, because of the immense monetary value placed on the swim bladders of this fish for use in traditional Chinese medicine. The swimbladders (maw) price depends on its age and shape, sex and size of fish, and even on the place and season of capture. In some markets, notably the Chinese markets, a good specimen swim bladder fetches more than its weight in gold.

Help urge more protection for this species by signing this petition online: “It is high time to protect the Chinese Bahaba”

Spawning populations are no longer known (fishing was targeted on spawning aggregations in estuaries in the past) and, given the heavy fishing pressure in the region, there are likely to be few or no refuges remaining for recovery. In addition, the estuaries in which this species spawns are degraded which may also have affected populations. It is not clear whether spawning aggregations of the species still occur, although some evidence suggests they might close to Xiqiyang, Dongguan, Pearl River. Dongguan by the way is one of Southern China’s biggest manufacturing cities.  Bahabas are vulnerable because of their biological characteristics of large size, restricted geographic range and aggregating behaviour in and around estuaries. When aggregating in estuaries they often produce sounds that makes individuals particularly easy to find.

By the 1990s, only small fish (<30 kg) were taken in Hong Kong waters sporadically, and large individuals (>50 kg) had become rare. Greatest catches were taken in the weeks prior to full and new moons with up to 300 fish taken in a season in Hong Kong in the past; now only the occasional small fish is taken. The last large Bahaba seen in Hong Kong was caught in 2008…

Source of the Father’s Day news item : Metro, 9/6/2014

Further Reading:
2001 article on the biology of the Chinese Bahaba from the “Porcupine” Newsletter of HKU’s Department of Ecology & Biodiversity

2010 blog post from Alex Hofford Photography on Bahaba products for sale in Sheung Wan

2012 Business Insider article of recent Bahaba catches and market prices

Hong Kong Federation of Women webpage detailing how expectant and new mothers can obtain fictitious health benefits by contributing directly to the extinction of the Chinese Bahaba
(FYI only, please don’t buy any Bahaba or Bahaba products!)

SCMP news item from 2008

Petition to for more protection of the Bahaba