‘Knife fish’ threatening native species in Laguna lake

The Philippines fisheries chief on Sunday said he had ordered a study into a foreign species called “knife fish” that was posing a threat to the fishing industry in the country’s largest lake.

The knife-shaped fish are reported to be multiplying in Laguna lake where they are displacing the native species, said Asis Perez, head of the Bureau of Fisheries and Aquatic Resources (BFAR).

“It is carnivorous. It will compete with our existing natural fish. We have yet to get a full appreciation of the damage caused by this fish,” Perez told AFP.

The fish, which can measure about 51 centimeters (20 inches) in length, was reportedly being bred locally as an ornamental species for aquariums but somehow got into the lake, which is located on the edge of Manila.

Fishermen’s groups have complained that their catch of native fish is shrinking, with their income threatened because people were not accustomed to knife fish as a dish.

Perez said this appeared to be the latest case of an invasive alien species harming the local environment.

In previous years, the suckermouth catfish, known locally as “janitor fish,” was introduced to local waters by ornamental fish breeders, where it displaced native species and damaged nets.

“This could be like the janitor fish. They were both introduced in the Philippines as ornamental fish. They could have escaped or they could have been intentionally freed,” said Perez.

The Philippines has only recently stepped up its concern over the introduction of alien species to native habitats, which can drive local species to extinction.

The country’s numerous porous ports have made it difficult to prevent the introduction of such species. In December, five people were arrested after they were caught with dozens of banned, carnivorous piranha fish they had brought into the country. AFP