Ateneo Researchers Warn of Invasive Tinfoil Barb in Laguna de Bay

Biologists from Ateneo de Manila University have issued a warning regarding the presence of an invasive fish species, Barbonymus schwanefeldii, commonly known as the tinfoil barb, which was discovered in Laguna de Bay—the largest freshwater lake in the Philippines. This alarming finding was confirmed after a specimen was collected in Barangay Patunhay, Cardona, Rizal, in September 2024, raising concerns over the potential ecological impact on native fish populations.

The tinfoil barb, characterized by its silver body and distinctive orange fins and tail, is typically found in Southeast Asian countries, including Thailand, Cambodia, Vietnam, and Laos. According to Dr. Kent Elson Sorgon, lead researcher and biologist at Ateneo de Manila University, "While this species is present in the ornamental fish trade, it has not been recorded in any freshwater ecosystems in the country."

The introduction of the tinfoil barb into Laguna de Bay remains unclear; however, scientists speculate it may have been either accidentally or intentionally released from aquariums, given its popularity in the aquarium industry. The research notes that this species is omnivorous and detritivorous, possessing a migratory behavior during the rainy season, which could facilitate its spread into neighboring rivers that feed into the lake. "The large area of Laguna de Bay and the migratory behavior of this species suggest that it may be more widespread than initially thought," Dr. Sorgon added.

The implications of the tinfoil barb's introduction could be detrimental to local fish species. The presence of this alien fish may lead to competition for resources, such as food and breeding grounds, with native species. "Our findings indicate that the introduction of non-native fish is a growing threat to the biodiversity of freshwater ecosystems in the Philippines," stated Dr. Maria Elena Abad, a marine biologist at the University of the Philippines Diliman and co-author of the recent study published in the Philippine Journal of Fisheries (2025).

According to data from the Bureau of Fisheries and Aquatic Resources (BFAR), nearly one-fifth of the 374 freshwater fish species recorded in the Philippines are non-invasive. The continuous influx of non-native species poses a serious risk to the ecological balance in the region. Local authorities have been urged to enhance monitoring efforts to manage the potential spread of such invasive species.

Moreover, the study emphasizes the need for public awareness regarding the ecological risks posed by non-native species. "We hope that local authorities can help raise awareness and implement strategies to monitor and mitigate the impacts of invasive species," Dr. Sorgon remarked.

As the situation evolves, experts stress the importance of documenting and verifying the presence of new species within Philippine waters to better understand their dispersal patterns. This incident highlights a broader issue of biodiversity decline in freshwater ecosystems, prompting calls for immediate action to safeguard native species against the threats posed by invasive fish populations.