The Mindanao Economic Development Council (Medco) said Taiwanese traders do not ship out their entire tuna catch to the US and Japan, but dump a sizable portion here, thus competing with local fishermen who use the handline method for fishing.
"We are trying to collect more data on the volume of what Taiwanese vessels reportedly dump here," a Medco source said.
However, reports said at least 60 percent of the total tuna catch of the Taiwanese vessels end up in the local market.
The social-economic unit of the Bureau of Fisheries and Aquatic Resources is expected to look into the matter.
The Mindanao Business Council, for its part, urged the government to review its transshipment policies and explore the possibility of imposing fees on foreign vessels using local ports.
Republic Act 8550 allows the use of local port facilities by foreign vessels for the transshipment of agricultural and fisheries products.
Transshipment by foreign vessels started in 1995, giving rise to tuna sashimi processing plants.