Viewing Facebook one day, I found myself reading a thread posted by a friend, Prime Jamethzkie, at the Monster Fish Keepers Philippines FB page. His post started with “MFKPh promotes responsible fish keeping!” and is supported by the Bureau of Fisheries and Aquatic Resources (BFAR) poster that reads, “Don’t Dump! Invading species threaten Philippine lakes and fisheries.”

This was such a great topic that it garnered at least 125 likes in a few hours and had a lot of comments and reactions from fellow fishkee pers. A lot of people shared their thoughts about the issue. For the most part, they supported BFAR’s campaign to encourage fishkeepers not to release aquarium fishes to our local waters. They were well aware of the implications of such an act and how it may eventually destroy the environment.

Unfortunately among those who commented, there were actually some who did not agree. Maybe they did not get the point, or just did not care or maybe they just did not have the capability to comprehend the issue because of their own selfish reasons. I would have reacted against their reply but then that would only solicit more negative comments from people who were outright defensive and to some point, arrogant. So with a lot of constraints, I held off my comments and decided to write this article instead because it means only one thing: not everyone is convinced of the dangers of introducing foreign fishes in our waters. Thus, there is a need to explain the facts and hopefully this article will clarify the issue and convince fishkeepers to understand the whole problem.

To have a better understanding of the issue, it is best to know the classification system used to determine the origins of fishes. This should put everyone reading this article on the same page.

Fish Origin Classifications


A biological taxon native to and restricted to a particular area or region and not found naturally anywhere else in the world ( Therefore, a fish is considered endemic if that fish species is only found in that country. An endemic fish I am quite familiar with is the Kanduli (Arius manillensis), a catfish that can live in fresh and salt water endemic to the island of Luzon and found in Laguna de Bay, Pasig River, and the waterways in Laguna, Bataan, Cavite and Navotas. If I am not mistaken, these catfishes can be caught in ManilaBay too.

Native of Indigenous

A biological taxon native to a particular area or region; but can be found naturally in other areas as well ( Therefore, a fish is considered native if that fish species is naturally found in that country and other countries as well. Surprisingly, the Dwarf Pygmy Goby or Philippine Goby (Pandaka pygmaea), which was originally reported from the Malabon River, it is considered native to the Philippines despite specimens recently having been collected in Bali, Sulawesi, and Singapore (

Introduced or Exotic

A biological taxon that is not native or indigenous to a particular area or region and that has been accidentally or deliberately introduced into the area ( Therefore, a fish is considered “introduced” if it is a foreign fish that has established itself here in the Philippines. A popular introduced fish that is commonly seen in the Pasig and Marikina Rivers is the Janitor Fish (Pterygoplichthys disjunctivus). This originally came from South America and has established itself in Philippine rivers.


If the introduced fish has established itself in local waters and has proven to have detrimental effects in the local ecosystem, then it is deemed invasive. An invasive species is defined as a species that is non-native to an ecosystem and whose introduction causes cause economic, environmental or health harm to humans ( An invasive fish species that recently caught the attention of the public is the Clown Knifefish (Chitala ornata). Being a top predator, it established itself in Laguna de Bay and ate its way to the top of the food chain. It has devastated the fishing industry in the area, causing losses for fish farmers and fishermen, and the extinction of some fish species.

What’s the Harm?

Many years ago, people never thought the introduction of foreign species in the environment could turn out to be an environmental disaster. In fact, in the 1950s, the Philippine government brought in the Mozambique Tilapia (Oreochromis mossambicus) from Africa for aquaculture. It was seen as a solution to alleviate hunger by providing additional protein for the Filipino people. It was a fish that was easily bred in fish farms and therefore proved to be a promising industry that could feed the people—until, of course, they escaped from the ponds and into the lakes and rivers. They propagated so fast that they quickly displaced local fishes. The local fishes could not compete for food and resources, and eventually became extinct in their own native waters.

Through the years, many more foreign fishes were introduced in the Philippines for aquaculture purposes. The Mudfish or Dalag (Channa striata), Thai catfish (Clarias batrachus), and rice paddy eel (Monopterus albus) were all introduced for aquaculture and have caused trouble in the Philippine environment; thus, they have been classified as invasive. The Dalag, being a predator, has become a pest in freshwater ponds since it preys on cultured species like bangus and tilapia. The Thai catfish has displaced the indigenous catfish (Clarias macrocephalus) in bodies of water where it was introduced. The rice paddy eel has reportedly harmed rice paddies in the Cagayan Valley by burrowing into dikes and causing water losses.

Fishes of foreign origin are introduced in the Philippines not only for food, but also for ornamental purposes. These are the aquarium fishes. These are our pets. Pets are a part of our lives. For an animal lover, a pet is a source of happiness and joy. We take care of our pets and ensure their needs are well provided for. We keep them healthy so they can keep us company. They mean everything to us. However, pets can become pests. From animals we adore, some eventually become pests and become a nuisance.

This is the case when pets are released to the environment. They eventually learn to live in their new habitat and compete for food and resources, and eventually, endemic and native species lose out in the competition. This is the purpose of the BFAR campaign: to convince you not to release your pet fishes in our local waters because they will harm our environment.

The Damage of Irresponsible Fishkeepers Have Done

A lot of foreign fishes have already been released in our local waters. The poster depicts the Clown Knifefish (C ornata), Jaguar Guapote (Parachromis managuensis), Janitor Fish (P disjunctivus and a few more species), Gloria (Sarotherodon melanotheron), and Giant Thai Snakehead (Channa micropeltes). This of course is just the tip of the iceberg. There are of course many more foreign fishes that have found their way in our waters and become invasive.

In some of the Facebook groups I am a member of, I have seen some fishkeepers share pictures of aquarium fishes they have caught in their local waterways. I remember some fishkeepers posted pictures of Mayan Cichlids (Cichlasoma urophthalmus), Flower Horns, Leopard Catfish (the crossbreed between Phractocephalus hemioliopterus and Pseudoplatystoma fasciatum), and Midas Cichlid (Amphilophus citrinellus), among others.

I am pretty much aware too that some fishes like the Tiger Barb (Puntigrus tetrazona), Aurelius Barbs (Dawkinsia arulius), One Spot Barb (Puntius filamentosus), Mollies (Poecilia sphenops), Guppies (Poecilia reticulata), and others are caught on the tributaries along Laguna de Bay and are sold in some pet shops. They are no longer farmed because you can just catch them in the waterways.

I personally do not believe that Laguna de Bay has been a haven for invasive fishes because it was work of a few fishkeepers who deliberately threw in those fishes in the Bay. For such a huge lake and such an extensive problem in terms of number of fish species involved and huge population of these invasive fishes in the lake, I do believe it required a massive introduction of these foreign fishes in the lake.

My theory is that Laguna de Bay is the largest body of water in Luzon because it is also the deepest part of the island. Therefore all waterways will eventually lead to the Bay. It is also a known fact that there are a lot of aquarium fish farms in Pila, Victoria and all other surrounding towns along Laguna de Bay. With an average of 22 typhoons a year, most certainly flooding will occur in these low-lying fish farms that would release aquarium fishes by the thousands—maybe ten thousand—enough to seed Laguna de Bay with introduced fishes that have the volume to reproduce to a viable population.

The fishkeepers may not have released them but the reason there are aquarium fish farmers in the surrounding areas of Laguna de Bay is the fact that it is a good industry that has fed their families for many generations. These fish farmers sell their produce to us, the fishkeepers.

Let us admit it to ourselves, our being fishkeepers make us liable in promoting this current problem of introducing invasive species in Philippine waters. Because we love aquarium fishes, these exotic fishes are brought in by importers and fish farmers because we want them. We created the demand. If there were no demand, then there wouldn’t be any aquarium fish industry.

This is the situation we are in. My take on this is that we should not be the problem, but rather the solution. So it is high time that we fishkeepers be more responsible in fishkeeping.

A man I look up to, Rafael Guerrero III of the National Academy of Science and Technology (NAST), in an article published in 2016 clearly pointed out the solution to the problem: “A massive information, education, and communication campaign to stir up public awareness for responsible aquarium pet care and environmental protection is recommended.”

Thus as fishkeepers we should take up this challenge. We should take part in this massive information, education, and communication campaign. We should educate fellow fishkeepers on the dangers of introducing our aquarium fishes in the wild. We must make sure our tanks are safe from flooding. We should be more responsible and protect our environment. In our own little ways, we can contribute, like sharing the BFAR poster with others. Let’s do our share. Don’t dump.

I also recommend that fish clubs, fish Facebook groups, and other organizations should have an adaption program for unwanted fishes. This not only prevents fishes from being thrown in local waters but it also gives other fishkeepers a chance to keep fishes. Remember that we the fishkeepers are not the problem, but we are the solution!

I just did my share in campaigning for this… when will you?


This appeared in Animal Scene magazine’s February 2018 issue.