Are you curious about the tilapia you have been eating? Did you know that tilapia strains that can be produced in both brackish water and estuarine environments have already been developed by Filipino researchers?
The University of the Philippines Visayas (UPV), with strong support from the Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development of the Department of Science and Technology (DOST-PCAARRD), has developed the UPV-Saline-Tolerant Population of Improved Nilotica (SPIN) tilapia strain.
This strain was designed to thrive in brackish water and estuarine to prevent mass death due to saltwater (saline water) intrusions, caused by rising seawater levels, in tilapia-producing areas.
An estuary is an area where a freshwater river or stream meets the ocean. In estuaries, the salty ocean mixes with a freshwater river, resulting in brackish water. Brackish water is somewhat salty, but not as salty as the ocean, the National Geographic.org said.
Most affordable, but declining production
For years, tilapia has been one of the most affordable fish in the country, and has been significantly contributing to the national economy.
Moreover, tilapia is the second largest aquaculture-produced fish species in the Philippines with a total production of 281,114-metric tons, valued at P24.26 billion in 2021.
However, the tilapia industry is currently exhibiting minimal or slow growth with an average annual production rate of 0.82 percent from 2012–2021.
The declining production trend has been attributed to the congested and saturated production systems in lakes and cages.
Thus, tilapia harvests in freshwater lakes and fishponds appeared to have reached its maximum capacity.
Dwindling water quality caused by mismanaged production and eutrophication (excessive plant and algal growth) of rivers and lakes are also factors linked to declining tilapia production.
To advance the industry production, tilapia farming is expected to expand toward the estuarine and brackish coastal areas.
It is found that brackish water ponds and estuarine water cages have high potentials for the growth and expansion of tilapia farming.
Best performing Philippine tilapia strain
Besides the UPV SPIN, two other saline-tolerant tilapia strains were developed in the Philippines, the Bureau of Fisheries and Aquatic Resources-Brackish water Enhanced Selected Tilapia (BFAR-BEST), and the BFAR-Molobicus strains.
To test the growth and production performance of these Philippine-developed saline-tolerant tilapia strains in different saline and brackish water ecosystems, UPV is conducting an investigatory research project, “Field testing and performance evaluation of saline-tolerant Philippine Tilapia strain cultured in different geographical brackishwater ecosystems.” It is also funded by DOST-PCAARRD.
The project aims to identify the ideal Philippine saline-tolerant tilapia strains for specific brackish water and high salinity coastal and riverine ecosystems.
Research results indicate that UPV SPIN and BFAR BEST tilapia strains exhibited faster growth and high survival rate in brackish water, high-saline pond culture systems, as well as in brackish water estuarine earthen ponds.
These strains attained the harvestable size of 250 grams in about 100 days of culture.
On the other hand, UPV SPIN showed the best growth performance in estuarine cage culture sites, compared to the two other tilapia strains.
Why the need for saline-tolerant tilapia strains?
The Philippines, being archipelagic, is surrounded by a wide range of brackish estuarine waters.
Its freshwater is being used not only for the culture of inland aquatic resources, but also for human household needs, consumption and agricultural irrigation purposes.
Due to the limited carrying capacity of freshwater, and to mitigate the declining water supply for aquaculture use, tilapia aquaculture is expected to expand its production in brackish and estuarine waters.
But this is only possible through the use of saline- or salt-tolerant strains.
This initiative hopes to significantly broaden and improve tilapia quality and production.
The adoption of the UPV SPIN strain technology in brackish water cages presents a notable advantage over other marine fish being cultured.
With the technology’s simple and cost-effective fry production, along with less technical needs in tilapia culture operations, it is highly accessible to small-scale, coastal fisherfolk.
It eliminates the need for significant investments and highly skilled technicians to run the aquaculture operation, thereby ensuring economic benefits in estuarine and coastal communities.
Rizza B. Ramoran/S&T Media Services
Image credits: UPV Project team