For decades, the rich biodiversity of Taal Lake has been a major source of livelihood and income, sustaining the lives of families living around its shores.

Located in Southern Luzon, Taal Lake is the third largest lake in the Philippines, with a maximum depth of 180 meters and an average of 65 meters. Surrounded by nine municipalities and two cities, it supports biodiversity and provides livelihood to thousands of Filipinos.

The lake is home to endemic species including tawilis (Sardinella tawilis), the world’s only freshwater sardine, and duhol matapang (Hydrophis semperi), a freshwater sea snake.

Its sole outlet, the Pansipit River, connects it to Balayan Bay and serves as a crucial migration route for species like the economically important maliputo (Caranx ignobilis) during spawning season.

Primarily used for capture fisheries, aquaculture, and tourism, Taal Lake plays a vital role in food security and the local economy, making its sustainable management increasingly essential.

NFRDI’s R&D initiatives in Taal Lake

Established through Republic Act 8550, or the Philippine Fisheries Code of 1998, the DA-NFRDI is mandated to lead research activities for the development, management, conservation, and protection of the country’s fisheries and aquatic resources.

One of its centers, the Freshwater Fisheries Research and Development Center (FFRDC), situated in Butong, Taal, Batangas, is an ideal site for fisheries research in Taal Lake, Pansipit River, and Balayan Bay.

Headed by Dr. Maria Theresa Mutia, Scientist I and concurrent NFRDI OIC, the Center plays a key role in the conservation of the lake and its resources. It has led extensive, long-term research to support fisheries management and conservation in Taal Lake and to help sustain the livelihoods of communities that depend on it.

On tawilis conservation

As the world’s only freshwater sardine and a species endemic to Taal Lake, tawilis holds both ecological significance and commercial value. The FFRDC undertakes conservation efforts through research and development programs in collaboration with various agencies, including

the Bureau of Fisheries and Aquatic Resources (BFAR) and the Department of Environment and Natural Resources–Taal Volcano Protected Landscape Protected Area Management Office (DENR–TVPL–PAMO).

The published study of Dr. Mutia on stock assessment reported a 50 percent decline in tawilis production over a decade span, prompting the International Union for Conservation of Nature (IUCN) to declare the species as endangered in 2018. The study also identified March and April as peak spawning months, supporting the issuance of TVPL-PAMB Resolution No. 49, which declared a closed fishing season during those months. An ichthyoplankton survey further identified four key spawning grounds: Balete, Mataasnakahoy, Pulangbato San Nicolas, and Cuenca, which were later designated as sanctuaries.

Meanwhile, a study published in The Philippine Journal of Fisheries in 2018 evaluated four gillnet mesh sizes: 3.39 cm (10k), 3.05 cm (11k), 2.77 cm (12k), and 2.65 cm (12.5k), during the tawilis spawning season in March and April. The study identified 11k (3.05 cm) as the optimal mesh size for capturing adult tawilis, helping prevent the premature catch of juveniles and supporting the species’ sustainability.

Further research conducted from 2014 to 2015 examined the ecological impact of invasive alien species on tawilis and other native species. Findings revealed an alarming rise in invasive species, from five in 1997 to 12 by 2015, including flower horn or Midas cichlid and kanduli, which threaten the survival and ecological balance of native populations, particularly tawilis.

A value chain analysis study published by Dr. Mutia in 2020 found that tawilis is primarily traded in local markets, either fresh or processed. Key players in the chain include fishers, buyers, processors, and consumers. Despite its limited market reach, tawilis remains a crucial livelihood source for small-scale fishers, highlighting the socioeconomic importance of its conservation.

These research findings were presented at various conferences and symposiums, including the Tawilis Summit held on February 8, 2019, and were publicly consulted with fisherfolk, local government units (LGUs), and other stakeholders.

On tilapia and bangus aquaculture

In addition to concerns about tawilis and capture fisheries productivity, the rapid expansion of cage aquaculture in Taal Lake has raised issues due to the heavy use of commercial feeds, a key concern for the TVPL-PAMB.

In response, a 2017 study evaluated the growth performance and cost-efficiency of extruded floating versus sinking feeds. Results showed that floating feeds reduced feed costs by 18–29 percent and feed usage by 20–30 percent, while maintaining production volume, leading to higher net returns. Based on these findings, the use of floating feeds was recommended for cage farming.

During the COVID-19 pandemic in 2020, the FFRDC supported Taal fisherfolk by promoting village-level hatchery and nursery systems for tilapia to enhance local fingerling supply.

On maliputo promotion

Maliputo, a high-value fish species, plays an important ecological and economic role in Taal Lake. A 2017 value chain analysis by FFRDC identified key bottlenecks and opportunities in the maliputo fishery to enhance value addition and fisherfolk income. Similar to tawilis, its trade remains limited to local markets. The study recommended exploring potential export markets and strengthening the promotion of maliputo as a premium product.

On GAD study

In support of inclusive and sustainable development goals, FFRDC conducted a Gender and Development (GAD) study on gender participation in Taal Lake’s fisheries sector. Published in 2020, the study highlighted the roles of both men and women, noting generally open access to resources. However, men dominated resource use and decision-making, especially in offshore fishing. The unequal distribution of responsibilities and male-centered programs were identified as key barriers to women’s full participation in fisheries.

Ways forward

To safeguard the long-term productivity of Taal Lake, NFRDI, through FFRDC, commits to advancing conservation, supporting fishing communities, and strengthening scientific collaboration.

Key initiatives include raising awareness on lake protection, providing alternative livelihood opportunities, and enhancing the enforcement of fisheries laws. In partnership with BFAR and other agencies, FFRDC will also develop breeding techniques for tawilis and conduct continuous stock assessments to promote sustainable aquaculture.

These efforts offer hope and stability to fisherfolk, who rely on Taal Lake for their livelihood. Through its R&D programs, DA-NFRDI remains dedicated to supporting the fisheries sector and empowering the communities that depend on it. ### (Vanessa Mae Escaño and Myla Muyot)