Freshwater sardine solely sourced from Taal Lake

by Catherine Teves

Researchers discovered the same morphological and genetic make-up for 'tawilis' (Sardinella tawilis) - the world's only known freshwater sardine solely sourced from Taal Lake in southern Luzon's Batangas province - and the Sardinella hualiensis fish inhabiting marine waters off northern Luzon's Aparri municipality in Cagayan province and harvested there as food.

"Our team's morphological and genetic findings indicate 'tawilis' and S. hualiensis are one and the same specie," said National Fisheries Research and Development Institute (NFRDI) scientist Dr. Mudjekeewis Santos who reported the discovery this week during the agency's scientific conference in Metro Manila.

He's convinced the evidence already warrants classification of both sardines as one specie only but acknowledged this matter is still open to scientific debate.

The discovery is fueling hope for better managing the commercially important but dwindling 'tawilis,' however.

"That's the initial reaction to our discovery as 'tawilis' is under fishing pressure already," Santos said.

National Fisheries Biological Center, Officer-in-Charge Frederick Muyot presented during the conference data showing that 'tawilis' production continuously shrank after 1998, dipping to some 107 metric tons (MTs) in 2010.

Last year's 'tawilis' production volume is merely about a tenth of the peak 1,120 MT output for this fish in 1998, the data also show.