I first spotted them on a random trip to Lake Sampaloc years ago: golden Fishes that from afar looked like Koi, but darted about like Cichlids. The fish were too far from shore to identify properly and it started to rain, so I never found out what they were.
Until a few days ago.
GOLDEN FISH
Returning this time with proper wet weather gear, we arranged for a special boat tour of Lake Sampaloc, the largest of the famed Seven Lakes of San Pablo in the province of Laguna. We met Jepolo Austria, a grizzled but friendly Fish farmer known around town as Mang Puloy.
“I will show you the golden Fish you are looking for. I have many of them in my floating farm,” says Mang Puloy as we paddle to the center of the lake, which is dotted with a motley array of floating Fish farms. After anchoring the boat, he balances on the farm’s weathered bamboo stilts and tugs at a slime-covered nylon rope.
Moments later, a wire cage emerges from the water. Jumping inside are four bright orange Fishes. One has beautiful white splotches, like a Japanese Koi. “I catch these golden Fishes and raise them in my bamboo Fish pens. I sell them for Php 100 per kilogram or Php 5 apiece. They are perfect for ponds because they look a bit like Koi.”
Though Mang Puloy originally raised Nile Tilapia (Oreochromis niloticus) and Bighead Carp (Hypophthalmichthys nobilis), his most colorful offerings are now these golden Fishes. “We call them ‘Flowerhorns,’ and they were introduced here sometime in 2015,” he adds.
Jepolo Austria, better known as Mang Puloy, has been raising Fishes in Lake Sampaloc for over 30 years. Among other Fishes, his floating pens hold the golden Fishes he calls “Flowerhorns.” (Gregg Yan / Best Alternatives)
BRIGHT ORANGE HYBRIDS
“Flowerhorns” are hybrid cichlids popularly kept in aquaria. Cichlids (pronounced “sick-lids”) are members of a large family of freshwater Fishes whose members range from the striped angelfish of the Amazon Basin to the Tilapia we know (discussed in previous issues of Animal Scene Magazine). I have documented them across the world, from the rivers of Southeast Asia to the world’s cichlid Mecca, Lake Malawi in Africa.
The “Flowerhorns” are possibly Midas Cichlids (Amphilophus citrinellus), native to Tropical and Central America, particularly in Costa Rica and Nicaragua. They are sought-after due to their bright and highly variable coloration, ranging from bright orange to jet black.
Highly aggressive, they grow about a foot in length and develop an impressive “nuchal hump”, a ball-like organ on their forehead. Midas Cichlids are often used to create hybrid “Flowerhorns” that in a few generations can revert to the “wild forms” of the Fishes used to create them.
There’s gold in Lake Sampaloc. Locally known as “Flowerhorns”, the golden Fishes can be found wild in Lake Sampaloc, the largest of San Pablo’s Seven Crater Lakes. They were originally native to Tropical and Central America and were introduced to the Philippines by hobbyists. (Gregg Yan/Best Alternatives)
PERHAPS UNWELCOME
Like Genghis Khan’s all-conquering Golden Horde (actually it was led by his grandson), the Golden Midas Cichlids have become successful invaders, establishing themselves in the United States, Malaysia, Singapore, and other countries.
“Having Midas Cichlids in our local lakes poses a threat to the continued existence of our economically-important native or indigenous Fish species since Cichlids are omnivorous and can feed on the larvae and juveniles of native Fish species,” explains Dr. Maria Rowena Eguia, Associate Professorial Lecturer at De La Salle University who has been studying aquaculture for the past 40 years.
“The ASEAN is rich in freshwater biodiversity. This is due to the presence of a number of inland lakes with unique geological history allowing them to support species and subspecies endemic to these water bodies. Introducing alien species into these closed systems will greatly impact the native species inhabiting the lakes,” explains Dr. Mundita Lim, Executive Director of the ASEAN Centre for Biodiversity.
“Tilapia and the infamous Knifefish, for instance, are predators [who] can devour endemic [F]ish species to extinction. Other invasive alien [Fishes], such as the Janitorfish, can compete with local species for food and space, thus eventually displacing them,” she adds.
ENDANGERING OTHER FISHES
Lake Sampaloc is the largest of San Pablo’s famed Seven Crater Lakes, all of which are interconnected. The golden Cichlids can possibly spread throughout the entire Seven Lakes System, dubbed in 2014 by the Global Nature Fund as its Threatened Lake of the Year 2014 due to pollution and the local extinction of its native Fish species.
In a 2016 study conducted by Jonathan Carlos A. Briones and team for the journal Tropical Ecology, nine of a dozen Fish species found living in Lake Sampaloc were invasive. There were only three native Fish species remaining: two types of Biya or Goby and the endangered Ayungin.
“These invasive [Fishes] can also feed on the larvae and juveniles of originally invasive but now economically-useful [Fishes] like [the Tilapia], potentially affecting our local [T]ilapia farmers,” adds Dr. Eguia.
AMONG OTHER INVADERS
After over an hour documenting Fishes, we finally leave Mang Puloy’s floating farm as the afternoon rains start to come in. Paddling back to shore, we see dozens of the golden Fish competing with juvenile Tilapia for algae. The old Fish farmer looks pensively at them. “I hope these golden newcomers do not affect my Tilapia farm too much.”
Invasive Fishes are threatening the country’s native aquatic biodiversity. In a 2008 paper published by Arsenia G. Cagauan in the Journal of Environmental Science and Management, over 170 foreign Fish species have been introduced to the Philippines in the past century.
Though beautiful to look at, the golden Cichlids are just the latest in a long line of finned invaders like the Clown Knifefish (Chitala ornata), Janitorfish (Pterygoplichtys and Hypostomus spp.), and the various Tilapia species that now dominate most Philippine lakes and rivers.
Fishers have already encountered and caught them in Laguna de Bay and even Taal Lake, home to endangered Pinoy Fishes like the Tawilis (Sardinella tawilis) and Maliputo (Caranx ignobilis).
To help stop the spread of invasive Fishes, another 2019 study by Jennifer A. Poniente and colleagues for The Philippine Journal of Fisheries recommended management interventions, such as tighter control measures to prevent the further spread of invasive species in Philippine lakes.
SOLUTIONS
One thing we can do is to stop the further spread of Midas Cichlids and other invasive Fishes in Philippine waterways by never releasing our animal companions in the wild.
Floating Farm. San Pablo’s Lake Sampaloc mostly grows Tilapia. Pollution and the introduction of invasive species have decimated its native Fish complement. A 2016 study found that only three of the lake’s 12 Fish species were native. The rest are imports that have taken over. Many Philippine waterways face similar scenarios. (Gregg Yan / Best Alternatives)
