This comment came from Simon Francis Blaise R. Bistro, a fellow blogger.

Before bangus (milkfish) fish cage operator rush and exchange their
fish nets into bamboo poles for “tahong” cultivation. It would be
enlightening to read some facts about the said shellfish.

The Philippine green mussel or “tahong” as it is locally known is
the only species of mussel farmed commercially in some areas in the
Philippines. It is known scientifically as Perna viridis.

P. viridis is commercial important because of rapid growth rate and
high population densities (Rajagopal et al. 1997). The green mussel is
also a good candidate for cultivation because reproduction can be induced
throughout the entire year (Sivalingam, 1977; Coeroli et al., 1984).
The mussel can also be transplanted from one environment to another with
little adverse effects(Parulekar et al., 1982).

Salinity tolerance: The high growth rate of the green mussel is related
to high salinity and an abundance of phytoplankton(Chatterji et al.
1984). According to Sivalingam (1977), the bivalve has a 50% salinity
tolerance between 24 and 80 ppt. The green mussel has a high tolerance for
reduced salinities, increased survival during atmospheric exposure, and
high survival rates in turbid water (Morton, 1987).

Temperature tolerance: Chatterji et al. (1984), also demonstrated that
growth was significantly affected by temperature. According to
Sivalingam (1977), between temperatures of 10-35°C the green mussel is 50%
temperature tolerant.

The bivalve has also been used as an indicator of biopollution of heavy
metals, organochlorines, and petroleum hydrocarbons (Bryan, 1976).
According to Philips (1980), and IOC (1981), P. viridis is one of the best
mussel species to test for biopollution.

The impact potential of a species is expressed in terms of their actual
(or potential) impact to human health, economic and environmental
impacts. P. viridis has been categorised as one of ten potentially most
damaging species. The potential international target species are
prioritised by their location in the invasion potential/impact potential space.
P. viridis has been categorised as 'High priority'. (Hayes et al. 2005)

Threat to humans: They can be carriers of diseases and parasites
harmful to native species. P. viridis has also been recorded with high levels
of accumulated toxins and heavy metals and is linked to shellfish
poisoning in humans.

Personally, this is a cause of alarm rather than an applause for the
apparent economic benefits because “tahong” is not known to be
endemic in the waters of Bolinao. Their proliferation and species adaptation
in the area would mean that there is high pollution in the waters of
Bolinao (due to irresponsible Bangus fish culturing?).

The western Pangasinan town of Agno faces another environmental headache. More than a month ago, a barge carrying 4.6 metric tons of coal ran aground off the shore of this town, and residents feared the coal could spill out into the sea and wreak havoc on the marine environment.
 

On December 18 last year, a barge marked San Miguel Pilsener owned by Asian Shipping Corporation grounded off sitio Talisay in Macaboboni village. It came from the port of Semirara, Antique and was on its way to PNOC Exploration Corporation in San Fernando, La Union.
 

Macaboboni village is that beautiful place facing the South China Sea. It was the proposed site of a multi-billion peso cement plant complex proposed by Goldsun Corporation of Taiwan. The project did not push through because first, the residents opposed it. Second, the proponents were not able to introduce any development during the lifespan of the project’s environmental compliance certificate.
 

Residents told the local police that the barge docked because of strong winds, but the police who investigated the incident reported that the barge had ran aground.
 

Last Janaury 21, Inspector Leonardo Navalta, town police chief, inspected the area and found that some coal had spilled on the sea shore and “this could have caused the seaweeds to die.”
 

“It was possible that strong winds and big waves which topped the barge caused the coal to spill,” Navalta said.
 

Lydia Colobong, and environmental activist from the town, said the village boasts of white sand but bits of coal has started to mar the unspoiled scenery. The coal could also have caused the seaweeds in the area to die, and would eventually also cause the corals to die, too, she said.
 

Navalta observed that the shore looked like it was topped with black cement.  
 

“I have reported the incident to all concerned agencies and I hope they act fast,” he said.
 

The Philippine Coast Guard based in Sual and the agency’s marine environmental protection office based in La Union  conducted inspection in the area but it still has to make public its report.
 

A report of the Community Environment and Natural Resources Office in Alaminos City showed that the boat captain denied throwing coal and causing marine pollution.
 

Boat captain Norman Nueva, quoted by Cenro, said coal was an expensive mineral thus he cannot afford to throw it into the sea. He also he knew it can cause marine pollution, he said.
 

Eugenio Santos Jr. of the Cenro told the Inquirer that he will recommend to the vessel’s owners to take immediate measures to remove the coal from the barge immediately.
 

Nueva is reportedly working on floating the 1.5- ton vessel and had told the police that he was bringing tug boats to float it. He also told the police that he would have the coal hauled by trucks.
 

He also refuted reports that spilled coal caused the seaweeds to die. “The wave action caused by strong winds uprooted the seaweeds,” he claimed.
 

But Colobong said while it was true that waves caused by strong winds uproot seaweeds, “not this massive scale and the weeds float still alive, not dead.”