The Little Paradisefish from My Ancestors’ Homeland (Full Article)Author: Lo Shiang Huei (Michael Lo)
When I was a little boy, my grandfather used to tell me about his childhood in northern Hong Kong, before he migrated to Borneo in the early 20th century. My favorite story was about his discovery of a species of labyrinth fish not far from his house. It was black/bluish colored with very long fins, and it would build a bubblenest for its eggs. I believe it was the black paradisefish Macropodus hongkongensis.
It was always my dream to visit my grandfather’s birthplace and find the black paradisefish. Not long ago, my good friend from China, Zhou Hang, caught this fish in a stream in China’s Guangdong Province. I was very excited to hear this news and immediately phoned him, and he invited me to come over.
Traveling in China
In April 2008 I flew to Macau, and from there I took a ferry to Hong Kong and met Zhou at the harbor. Zhou said that M. hongkongensis is a protected species in Hong Kong, so we had to look for this fish beyond that region. We took a bus to Shenzhen, a city in southern China, and arrived at Zhou’s place downtown around midnight.
We woke up early in the morning, and Zhou’s friend, Mr. Wang, a naturalist who likes collecting and photographing invertebrates, joined us for a cab ride to the bus terminal. We then took a bus to the town of Haifeng, and from the bus window I enjoyed the beautiful scenery, which is totally different from tropical Borneo. Zhou said that most of the rivers in Guangdong Province are polluted and there are few places to collect fish. Guangdong is one of the fastest-developing areas in China, but this is very bad for many freshwater fish habitats.
Zhou took a local map from his bag. He pointed out that rivers near Haifeng are relatively short compared to other rivers in the province. The surrounding mountain ranges divide the river system at Haifeng from the main drainage system. “There is a good chance that we could find a new endemic species of fish in this area,” he said with confidence.
A few hours later we arrived in Haifeng and, after having lunch, found a motorcycle taxi. The taxi was very similar to the tuk-tuks (auto rickshaws) of Bangkok. After bargaining the fare with the taxi driver, the three of us squeezed into the box-like seat of the taxi and rode to a village in the foothills of Mount Lianhua. The taxi dropped us off at a Buddhist temple, behind which rose the ever-green mountain, its summit covered by mist.
Day 1: New Species and Assorted Finds
There was a stream about 5 meters (16 feet) wide next to the temple. Zhou told me I could collect some paradisefish there the next day, but as it was late, he wanted to show me some hillstream loaches in the upper part of the stream.
We walked slowly along the stream and came upon a bulldozer. The stream water had been crystal clear, but here it was brown with silt from the construction work for a local resort. About 15 minutes beyond this site, Zhou left his bag on the roadside and ran down to the stream to look for fish while Wang trekked into the nearby bushes to collect insects. I took out my camera and began snapping pictures of both as they busily hunted the wildlife.
Zhou shouted at me to bring a plastic bag. I took his bag and walked down slowly on the slippery rocks toward Zhou. He showed me what he caught in his fish net—a freshwater goby about 4 cm (1½ inches) long with a very striking color. The body was brown with red blotches down the side. Zhou was very excited because this goby could be a new species, and he later sent the goby to an ichthyologist who confirmed it. The goby was subsequently described as Rhinogobius zhoui, named after Zhou.
After putting the fish into the plastic bag, Zhou continued to look for other fish. While I was busy photographing the fish swimming around me, Zhou shouted with excitement again. This time a little catfish with beautiful stripes was jumping in his net. This rare catfish, Pseudobagrus trilineatus, is only 7 cm (2¾ inches) long, and Zhou had been looking for it for many years. I was amazed that such a small stream could support this variety of freshwater fish, which also included some loaches clinging to the rocks in the fast-flowing stream. Pseudogastromyzon laticeps is an endemic species of hillstream loach that looks very similar to Borneo suckers Gastromyzon spp. from Borneo, except that it has a slightly pointed snout.
At around 2 p.m., we walked back and found a restaurant next to a river. Local delicacies included a plate of cooked freshwater snails collected from the river. After taking our lunch, we walked across the street to a wider river. Zhou pointed to some native fish swimming in it and told me their scientific names, one after another.
He then led us to another stream next to an open field to find the location where he discovered a patch of Cryptocoryne crispatula var. “crispatula” about two years ago. He could not remember the exact location, so it took several hours for us to find it along the stream. At 6 p.m., as the sun was setting behind the mountain, Zhou suddenly ran into the stream and yelled at us, “Shu cao! Shu cao!”—Cryptocoryne in Chinese. I quickly ran toward him and was stunned to see a big mass of C. crispatula var. “crispatula.” After taking some photos and collecting some plants, we left to get dinner, but Zhou set up a gill net in the river next to the restaurant just before dark.
After dinner we went to check the gill net. It had only caught four species of cyprinids: Zacco platypus, Opsariichthys bidens, Rasbora steineri,and Parazacco spilurus. We released the fish back into the river after photographing them, and saw catfish and gobies coming out to look for food as it turned dark. We also found a few species of freshwater shrimps and apple snails crawling on the riverbed. The apple snails are an introduced species and have become pests, eating crops and carrying the parasite Angiostrongylus cantonensis, which infects humans. It was getting late, so we returned to Haifeng.
Day 2: Paradise Retrieved
It was misty the next morning in Haifeng. We took a motorcycle taxi back to the village and hired a native kid to be our guide to climb the mountain there. The mountain is about 4000 feet high, so we estimated it would take four hours to reach the summit. Half an hour later, though, we decided to stop climbing; we decided we could not find any flora and fauna that interested us in this type of subtropical forest. We instead went to visit a waterfall.
There was an unpolluted stream nearby that had a large population of the goby Rhinogobius zhoui we discovered the day before. Zhou took up his net and collected at least 20 adult fish for taxonomy purposes. Right after he passed me the plastic bag of gobies, he quickly jumped back into the water. He came back with a beautiful Opisthotropis water snake in his hands, which he held out for me to photograph. Zhou is crazy for all kinds of reptiles, and he announced that we would look for more snakes later that night.
Next we went to the lower part of the stream and caught Schistura fasciolata, a beautiful loach having a dark, orange-colored caudal fin, an algae-eating shrimp Caridina sp., other types of gobies (Rhinogobius duospilus and Hypseleotris compressocephalus), hillstream loaches Pseudogastromyzon laticeps, and Oryzias latipes. We took a break to enjoy the light meal we’d brought with us and continued to look for fish along the riverbank.
Around 3 p.m., Zhou finally caught the fish I was looking for—a male black paradisefish Macropodus hongkongensis! I was fascinated to see its dark bluish-colored scales gleaming in the sunlight. The spot where Zhou caught the fish was a slow-flowing stream with a bank covered by dense vegetation.
We walked farther and discovered a much bigger area of C. crispatula var. “crispatula.” The undulated leaves of the Cryptocoryne were extremely long; some of the leaves even reached 30 cm (12 inches). We were stunned to see such a huge population of the water plant in front of us.
After dinner, we turned on our flashlights and walked along the river again to the upper part of the stream to look for amphibians and reptiles. We saw a lot of gray-colored catfish Pterocryptis cochinchinensis swimming in the deeper part of the stream. This catfish hides under the rocks during the daytime and only comes out after dark to search for food. It has a pair of long whiskers to help it to navigate the water or search for food at night.
But Zhou was not interested in catfish. He jumped from one rock to another and caught a few species of frogs with Mr. Wang, and then showed them to me and told me the natural history of each species. The croaking of the frogs was so loud that it seemed to fill the entire valley. We left after a few hours without having found any snakes, just lots of frogs.
Day 3: Farmlands
On the third day of collecting, Zhou and I woke up very early and left Wang sleeping in the hotel room. We took a motorcycle taxi to a nearby fish market to look for any interesting native fish. I saw people selling snakeheads, carps, and small freshwater fish from the river. Among those fish, I saw the common paradisefish Macropodus opercularis and a beautiful barb called Puntius semifasciolatus. Both species used to be popular ornamental fish kept by aquarists throughout the world.
Here the small fishes were being sold to farmers to feed their ducks. Zhou explained to me that M. opercularis is the most common paradisefish in southern China. It is usually found in the stagnant water of drains and waterways in the countryside and does not share the habitat with M. hongkongensis, which prefers to live in the upper parts of clear and unpolluted streams. From the market, we took another taxi to a nearby farmland.
Twenty minutes later, we arrived at a place where there were a lot of drains and ponds next to a farmhouse. The surface of the water was completely covered by floating plants. Zhou wore his wetsuit and went into the pond to look for M. opercularis. I wanted to follow but was stopped by Zhou because I did not have a wetsuit to protect my legs; he warned that there are parasitic worms in the polluted water.
There were a few species of water plants that I had never seen before growing abundantly in the drain. Two types of those plants could be Potamogeton and Polygonum. Zhou did not catch anything in the drain, as the fish population was too low. The water was very smelly and polluted with pesticide washed down from the farmland. We walked on a dirt road to look for a less polluted stream. Half an hour later, we found a clearwater stream in a grassland where there were a few cows grazing.
At the edge of the stream, we caught a few snakeheads Channa asiatica and the climbing perch Anabas testudineus. Channa asiatica is a predatory fish from southern China. The population of this snakehead has been decreasing in recent years due to overcollection by native people, as it is one of the important food fishes there.
Before leaving the farmland, I caught a juvenile tilapia Oreochromis mossambicus. Tilapia is considered by some to be the most widely distributed fish genus in the world, as various species can adapt to almost any type of habitat. It was introduced to China for aquaculture purposes. Unfortunately, some escaped from the fish pond to the river and now propagate widely in southern China and have become a threat to native species, as they eat anything they can fit into their big mouths.
Later at noon, we went back to town to meet Wang. After lunch, we bought bus tickets back to Shenzhen in the afternoon. Since the day we left was the Monday after a long weekend, the expressway was congested with traffic. By the time we reached Shenzhen, it was already very late at night.
Day 4: Xi Chong
On the second to last day before I left China, Zhou had to say goodbye because he needed to fly to another city for work. I took my luggage and checked into a hotel next to Zhou’s apartment. Wang later came to see me and wanted to bring me to another location to collect black paradisefish not far away from Shenzhen.
It was a sunny Monday morning. Two of us took a public bus and traveled for two hours to our destination, Xi Chong. Xi Chong is a small town where most of the local people speak Hakka, a dialect I am familiar with. From that town, we took a motorcycle taxi to a village near the coastal areas. It was not a comfortable journey; the road was very hilly and winding.
Half an hour later, the driver dropped us off at a village surrounded by hills. When we were walking by some abandoned fish ponds and a small river, I saw some brackish-water fishes swimming in a school. I felt a little bit puzzled about the place.
“Is it possible to find paradisefish in brackish water?” I asked Wang. He replied, “No, they are only found in freshwater streams, farther up this brackish-water river.”
We walked past an open field and reached a quiet and slow-flowing clearwater stream. Both sides of the bank were covered with thick bushes and bamboo. While photographing the habitat, I saw something swimming on the water surface. I scooped it up using a fish net and found it to be a mosquitofish Gambusia sp., a species introduced to this stream. The substrate of the stream is mainly sand and the bottom is covered by a layer of leaf litter. There was no sign of paradisefish—in fact, nothing was visible except the rubbish dumped by the villagers upstream.
After searching for the fish in different spots for an hour, I finally caught a female black paradisefish hidden in the leaf litter next to a sand bank. After taking pictures, I kept the fish in a container we brought along and then went to eat seafood at the nearby coastal town.
Bringing Black Paradisefish Home
A few months later, the pair of black paradisefish that I brought home spawned in my 4-foot long aquarium. It is a community tank with small barbs, rasboras, and bettas. First, the male built a 5-cm (2-inch)-wide bubblenest at the corner of my aquarium. I did not pay attention to it until, one day, I saw that the male paradisefish became very aggressive and territorial. It attacked and chased away any fish that came near the corner of the fish tank.When I looked closer, I saw at least 20 paradisefish fry swimming near the water surface. I was shocked to see those juveniles, as no other fish had managed to breed in the community tank before. By keeping those paradisefish in my tank, I will always remember my great journey with my friends in China, and most of all, my late grandfather who was the first to tell me about this fish.
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