Long-term threat to Mauritius ecology after spill: Japan experts

This handout picture taken on August 22, 2020 and received from the Japan International Cooperation Agency (JICA) on August 25 shows a JICA expert confirming oil drifting in swamps where mangroves live in Mauritius. – The major oil spill caused by a Japanese ship that ran aground in Mauritius may pose a long-term threat to the region’s ecology, including to the Indian Ocean island’s delicate mangroves, Japanese experts said on August 25. (Photo by Handout / Japan International Cooperation Agency / AFP)

TOKYO, Japan (AFP) — The major oil spill caused by a Japanese ship that ran aground in Mauritius may pose a long-term threat to the region’s ecology, including to the Indian Ocean island’s delicate mangroves, Japanese experts said Tuesday.

The bulk carrier MV Wakashio crashed into a reef last month spewing more than 1,000 tonnes of oil into pristine waters that are home to mangrove forests and endangered species.

After the boat split in two, the larger piece was towed out to sea and sunk, but the smaller section remains stranded on the reef.

Japanese experts and officials in Mauritius said they had surveyed a dozen marine spots about 800 metres (yards) northwest of the wreck, and found no major damage, nor any sign of oil on the ocean bottom or on the coral reef.

This August 12, 2020, handout satellite image obtained courtesy of Maxar Technologies shows the oil containment booms in place along the shoreline of Mauritius. – Salvage crews have successfully pumped all the fuel from the tanks of a giant cargo ship which ran aground off Mauritius, the prime minister said August 12, 2020, preventing another massive oil spill into the pristine waters. Further ecological disaster was averted as the MV Wakashio, a Japanese-owned bulk carrier, threatens to break apart at any moment after more than two weeks stranded on a coral reef off the island nation. (Photo by Handout / Satellite image ©2020 Maxar Technologies / AFP)

But they said the remaining wreck appeared to be grinding against the reef as waves push it back and forth.

“If this situation continues, it could cause stress to the corals and could kill them,” said Noriaki Sakaguchi, an ecosystems expert with Japan International Cooperation Agency.

He said efforts to remove sediment could harm the coral, which is also being damaged by ropes holding oil fences set up to stop the spill reaching shore. Removing the remaining wreckage appears to be the only solution to the problem, the team said.

This handout picture taken on August 22, 2020 and received from the Japan International Cooperation Agency (JICA) on August 25 shows a JICA expert confirming oil drifting in swamps where mangroves live in Mauritius. (Photo by Handout / Japan International Cooperation Agency / AFP)

The spilled oil has also reached the soft soil of mangrove forests along the coastline.

While there is no evidence of mangrove death yet, the oil could kill plants in the protected area in coming months, the team warned.

Mangrove clean-up is extremely complicated because human activity in the area risks driving oil deeper into the soil where it could cause more harm.

For now, cleanup efforts are focused on picking up seagrass and other plants that wash through oil-covered areas and end up on the shore.

The team called for long-term monitoring of the area after the accident, which is still under investigation by Mauritian authorities.

This August 19, 2020, handout satellite image obtained courtesy of Maxar Technologies shows an overview of the forward section of the MV Wahashio shipwreck and two tug boats off the coast of Mauritius. (Photo by Handout / Satellite image ©2020 Maxar Technologies / AFP)

Japan’s Kyodo News said Monday that crew on the ship had steered it close to shore because they wanted to find a mobile signal so they could contact family and ask about the coronavirus situation at home.

It cited an unnamed judicial source, who also said an alcohol-fuelled birthday party had been held on board before the accident, though it was not clear if on-duty crew participated.

© Agence France-Presse