Conservation news

Civil war didn’t hurt this Sri Lankan mangrove forest, but shrimp farming might

  • Environmentalists have opposed plans to establish shrimp farms in the Vidattaltivu nature reserve, home to an important mangrove forest and biodiversity-rich marine habitat in northern Sri Lanka.
  • Critics say the plan goes against the government’s wider efforts to conserve mangrove areas.
  • They also point to the failure of a similar project to establish firm farms in a mangrove area, which resulted in 90% of the farms being abandoned because of disease outbreaks among the shrimp.
  • The plan also threatens the hundreds of thousands of migratory birds that stop to feed in the area during their long journeys along the Central Asian Flyway.

MANNAR, Sri Lanka — The Vidattaltivu coastal belt in Sri Lanka’s north was once home to the marine unit of the Tamil Tiger guerrilla group, known as the “Sea Tigers.” From here, the group launched explosive-laden suicide boats in attacks against the much more powerful fighter vessels of the country’s naval forces. The area’s lush mangroves proved an effective hiding place for storing explosives.

More than a decade after the end of the civil war, the ecology of this picturesque nature reserve is under threat: there are plans to set up a shrimp aquaculture park here, which environmentalists have blasted as “environmental suicide.”

Sri Lanka has a bitter history of shrimp farms going wrong. In the 1980s, large swaths of mangroves in the northwestern coast were cleared to farm shrimps for export. But frequent outbreaks of disease led to about 90% of the shrimp farms being abandoned.

Vidattaltivu is a nature reserve with great significance for biodiversity. Image courtesy of the Environmental Foundation Limited (EFL).

Failed shrimp trade

“With such a history of failure, proposing aquaculture for the Vidattaltivu nature reserve is a crime against nature,” Hemantha Withanage, executive director of the Centre for Environment Justice (CEJ), told Mongabay.

Vidattaltivu is a biodiversity-rich ecosystem consisting of mangroves, tidal mud flats, salt marshes, seagrass beds and coral reefs. In recognition of its importance, the government declared nearly 30,000 hectares (74,000 acres) of the area a nature reserve in 2016.

But in a recent move, the government’s National Aquaculture Development Authority (NAQDA) has proposed developing more than 1,000 hectares (2,500 acres) of shrimp farms inside Vidattaltivu.

“Building roads, common inlet and outlet canals, sedimentation tanks and water storage areas for private investors to use the area for aquaculture are part of the proposed project,” Nimal Chandraratne, director-general of NAQDA, told local media at a recent briefing.

He said the mangrove belt will remain intact and unharmed, and that all possible environmental safeguards would be taken. The project is estimated to generate around 4,500 jobs and about 8,500 tonnes of seafood for export annually.

But these assurances of environmental safeguards have not convinced environmentalists who oppose the plan and cite Sri Lanka’s  poor track record in monitoring and enforcement as additional concerns.

“There were guidelines and environmental controls in place when shrimp farms in the northwestern Puttalam lagoon commenced,” Withanage said. “But the system’s failure was such that over 3,000 hectares [7,400 acres] of aqua farms had to be later abandoned. The local community hasn’t benefited and local fisheries in the region collapsed. Nobody takes responsibility for the environmental disaster caused.”

Vidattaltivu boasts an expansive mangrove forest and mudflats, home to a wide range of species. Image courtesy of Dinal Samarasinghe.

Environmentalists say the proposed project’s indirect impacts include potential disease outbreak and seepage of chemicals from shrimp ponds into the ocean, harming the fragile ecosystem consisting of corals and seagrasses. “It is very likely that pesticides, antibiotics, chlorine and other water-quality-regulating chemicals and fecal matter of farmed species would get discharged into the ocean,” Withanage said.

Experts are now calling for a sound economic analysis, including the value of ecosystem services that would be lost due to the project, in a bid to assess the project’s benefit.

“This type of project in an environmentally sensitive area is beyond a traditional environmental impact assessment [EIA],” said Ananda Mallawatantri, current country head of IUCN Sri Lanka who, during a previous stint with the UNDP, led an integrated strategic environmental assessment (ISEA) of the island’s Northern province, where Vidattaltivu is located.

“We need to do an ecosystem economics study in line with natural capital accounting, comparing the potential impacts on traditional fishery, corals, seagrass and so on, together with ripple effects on the other sectors in the short and long term to calculate the actual benefits,” Mallawatantri told Mongabay.

“The environmental impact analysis should consider long-term impacts to the natural ecosystem over a long period of time and the dilution [of quality] factor. A project should be given the green light if an in-depth analysis still indicates much higher benefits,” he said.

It was Mallawatantri’s ISEA that helped lead to Vidattaltivu being declared a protected area. “The idea was to achieve sustainable development without disturbing the balance in nature. The recommendation was made as the scientists associated with the ISEA considered the potential damage to the ecosystem would be irreversible and will bear multiple impacts,” Mallawatantri said.

A near-threatened blacktip reef shark (Carcharhinus melanopterus) swims over a coral bed in the Vidattaltivu Sea. Image courtesy of Nadika Hapuarachchi.

Global commitment to protect mangroves

The new attempt to strip protection for one of the most important mangrove forests in Sri Lanka comes as the country’s mangrove conservation efforts are getting global recognition. In 2018, Sri Lanka pledged to champion collaboration on mangrove restoration as part of the Commonwealth Blue Charter. In 2019, Sri Lanka and Indonesia jointly submitted a resolution to the United National Environmental Assembly urging global action to conserve mangroves.

Sri Lanka has already declared 76 mangrove patches as forest reserves and plans to add 12 more under the protected area scheme this year. In January, the country’s parliament endorsed a Mangrove Conservation Policy under which the island nation intends to achieve a mangrove restoration target of 10,000 hectares (24,700 acres) by 2030. A pilot project by the Department of Forests is leading an effort to restore several abandoned shrimp farms.

Despite all these measures to conserve and protect mangroves in Sri Lanka, the pressure to degazette Vidattaltivu continues, said the Environmental Foundation Limited (EFL) a Colombo-based group, which cautioned against activities violating the national policy.

In 2018, the spoon-billed sandpiper, a critically endangered bird, was recorded in the Vankalai Sanctuary, adjacent to Vidattaltivu. Image courtesy of Ravi Darshana.

A bird paradise

Ornithologists are among the many groups concerned about losing Vidattaltivu, among the most important overwinter mudflats of the Central Asian Flyway, a key bird migratory route of global significance.

Vidattaltivu borders the Vankalai Sanctuary, a Ramsar wetland and home to many native birds and hundreds of thousands of migratory birds.

Sampath Seneviratne, an ornithologist and senior lecturer at the University of Colombo, said most of the bird species that frequent Vankalai also use about 50% to 80% of Vidattaltivu nature reserve for feeding, roosting and breeding.

“Some think that birds can use Vankalai in the absence of Vidattaltivu, which is incorrect, as the tidal mudflats open and close in a rhythmic manner throughout the year,” he told Mongabay. “Birds and other aquatic fauna need both Vankalai and Vidattaltivu to maintain a rotation in their feeding and breeding.”

For millions of years, birds have used the same winter migratory route and lack the genetic capacity to change their migratory routes in response to sudden changes in the landscape, such as clearing of large swaths of mangrove forests and mudflats, Seneviratne said.

An estimated 40,000 to 80,000 shrimp-eating birds stop over annually to feed. If the shrimp farms are built, these birds will feed from them, leading to conflict between the farmers and the birds, Seneviratne said.

“In the northwestern areas of Puttlam and Kalpitiya, such conflicts have resulted in the mass killing of migratory birds and others being disturbed and chased away,” he added.

In Vidattaltivu, harvesting of prawns is traditionally done using mangrove branches, unlike commercial shrimp farming, which is inherently highly polluting and poses a threat to native species. Image courtesy of Dinal Samarasinghe.

The unknown shrimp

There are also concerns about the shrimp species likely to be cultivated on the farms. One such candidate is the Pacific white shrimp (Litopenaeus vannamei), which is not a native species to this Indian Ocean island. “Introducing alien species without due impact assessment to native species will cause ecological imbalances and health impacts,” the EFL said, calling for an assessment of the impact of such a species introduction.

It’s likely that some of the farmed shrimps will escape into natural habitats, especially during their microscopic juvenile stage. In the wild, they could turn into an invasive species, threatening native species by outcompeting them for food resources, the EFL said.

The Pacific white shrimp, also known as the king prawn, is known to carry diseases, creating a danger of disease transmission to wild shellfish populations and contributing to the possible collapse of native species and impacting local livelihoods, the EFL added.

 

 

Banner image of greater flamingos (Phoenicopterus roseus) in Vidattaltivu, a birds’ paradise and temporary home for many thousands of migrant bird species, courtesy of Nadika Hapuarachchi.