Thus far, the janitor fish's infiltration and domination of other fish in the Marikina River, in Metro Manila, have caused much dismay and frustration to local fishermen.

Along the soft, muddy banks, one can see holes, which the fish use as breeding nests. Soil gets washed away when the rains come and the  river water, which has turned milky-brown turbid, swells. This damages the plant life along the banks.

Cazar, who doubles as a ‘barangay tanod’ (village security) in Sto. Ni๑o, is a member of the local government’s ‘Oplan Alis Janitor  Fish’ (Oplan Eradicate the Janitor Fish). Launched in early 2005, the project offers to pay 20 centavos to residents for each janitor fish they catch.
Cazar estimated the ratio of the number of janitor fish to other  species in the river these days to be around 10-to-one. With the use of a fishing net, Cazar and other village officials, under local leader Domingo dela Paz’s supervision, haul in some 10 tonnes of janitor fish daily.

Dela Paz also rued the decrease in the number of fishermen in the  Marikina River after the janitor fish infestation. He said there used  to be some 100 fishermen in Barangay Sto. Ni๑o alone. Today, however,  only a small fraction of that number remains.

Another potential solution to the janitor fish menace is the  discovery by 16-year-old Raymond Joseph Amurao that oil extracted  from the janitor fish could be used to make soap and, more  essentially, bio-fuel.

The incoming college freshman told Asia Water Wire that his mother Janet, a chemistry teacher, introduced him and his classmates to the  janitor fish. Janet is a member of the committee organised by Marikina City to solve the water-related problem.

He first sought to turn it into a lubricant, but it solidified after  being subjected to high heat. Afterward, he tried mixing the oil with other chemicals to produce soap, but had partial success with it  because it possessed a fetid smell.

“The biodiesel derived from the weird-looking fish could be utilised  as an additive to diesel fuel, and hence could help considerably  lower the cost of petroleum in the country,” Amurao told AWW.

“If it actually works, this could become a great source of livelihood  in Marikina," he beamed.

MENACE OF A FISH

Although it did not pose any direct threat to people and other fish, this abrasive, exoskeleton-skinned creature wrought havoc to the river’s ecosystem.

Residents, particularly children, initially became fond of the  prehistoric-looking fish, which were caught and placed in aquariums.

Somehow, the fish made it into the city’s river system, which flows down to the Laguna de Bay, a lake a few hundred kilometres south-east  of Marikina. The bay serves as a catch basin for 15 water tributaries  around it.

With support from the Marikina mayor and the government’s Laguna  Lake Development Authority, Amurao sees his janitor fish biofuel  innovation becoming commercially viable within two years’ time. He further said he plans to sell his organic fuel at 50.15 pesos (1 dollar) per litre. This is quite cheap considering that it would be used sparingly, merely as an additive to commercial fuel.

Other possibilities include its being used in the production of carbonated water, liquid fertiliser, and chicken feed. (END/AWW/IPSAP/ EH/LC/JS/220906)