Thailand wages war against ‘alien’ tilapia fish

Thailand wages war against ‘alien’ tilapia fish

The black chin tilapia has been labeled as the “most invasive species” to ever strike Thailand, posing a significant threat to the environment, according to officials.

Efforts to control the species have involved large groups of people wading into lakes and employing genetic modification. Despite these measures, the black chin tilapia continues to spread across Thailand’s waterways, affecting 17 provinces to date.

A parliamentary investigation has been launched to determine the cause and those responsible, with Bangkok MP Nattacha Boonchaiinsawat stating, “We will not pass a devastated ecosystem to the next generation.”

The question now is whether Thai authorities can successfully combat this invasion and how this West African fish managed to wreak havoc so far from its native habitat.

Although Thailand has faced black chin tilapia outbreaks before, none have been as widespread as the current situation. Mr. Nattacha estimates that this outbreak could cost the Thai economy at least 10 billion baht ($293 million; £223 million).

The primary issue is that black chin tilapia prey on small fish, shrimp, and snail larvae, which are crucial to Thailand’s aquaculture industry.

For several months, the government has encouraged people to catch black chin tilapia, which have infiltrated rivers and swamps. The fish thrive in brackish water but can also survive in both fresh and saltwater.

In response, the Thai government has doubled the bounty for catching the fish to 15 baht ($0.42; £0.33) per kilogram. This has led to crowds in Bangkok’s suburbs wading into knee-deep waters with plastic basins, hoping to catch the invasive species.

Authorities have also released the black chin tilapia’s natural predators, such as Asian seabass and long-whiskered catfish, to help control their population.

However, they are battling a species that reproduces at speed: females can produce 500 fingerlings at a time.

And so authorities have also gone to the extent of developing genetically modified black chin tilapia that would produce sterile offspring, planning to release them as early as the end of this year, in the hopes of stopping their population from exploding further.

But Mr Nattacha told BBC Thai the government needed to do even more.

“Who will win?” he wondered. “We need the people to follow the case closely, otherwise this matter will be quiet, and we will pass on this kind of environment to the next generation.”

So how exactly did this fish – easily identifiable thanks to the black spots on their chins and cheeks – come to be in Thailand?

One theory that parliament has looked into is that an experiment by food behemoth Charoen Pokphand Food (CPF) 14 years ago had caused the spread.

The company, which produces animal feed and runs shrimp and livestock farms, imported 2,000 from Ghana in late 2010. It said all the fish died and were buried properly.

Two years later, outbreaks of blackchin tilapia were reported in Thailand, including the area of a CPF laboratory, according to local broadcaster Thai PBS.

But CPF – the agribusiness arm of one of Thailand’s largest conglomerate, Charoen Pokphand Group (CP Group) – has rejected the allegations. It has also threatened to sue those spreading what it calls “misinformation” on the matter.

It is co-operating with state agencies fighting the spread of the alien species.

“Although the company is confident that it is not the cause of the outbreak, it is not indifferent and is ready to cooperate with the government to alleviate the suffering of the people,” said Premsak Wanuchsoontorn, CPF’s aquaculture and research development officer.

However, CPF officials have attended parliament hearings in person only once. They have previously given their explanation to lawmakers in writing.

The director-general of Thailand’s Department of Fisheries, Bancha Sukkaew, notes only one private company had sought permission to import blackchin tilapia.

He told the BBC that there was a possibility that some escaped from the laboratory.

However, he is also not discounting the possibility that the invasive fish species could have been smuggled into Thailand.

In the end, though, how they came to be in Thai waterways is the past – the problem is the future, and getting the outbreak under control. But is it possible?

Experts told BBC Thai that the battle against the blackchin tilapia could be a losing one.

“I don’t see the possibility of eradicating it,” said Dr Suwit Wuthisuthimethavee, an expert in aquatic animal genetics at Walailak University.

“Because we cannot limit its range. When it is in nature, it reproduces continuously, has a fast reproductive cycle,” Dr Suwit added.

Nonn Panitvong, an expert in freshwater ecosystems, agreed.

“The problem with alien species is that once they are established, they are very difficult to eradicate,” he said.