Mauritius Has Reminded the World of the Looming Threat of Oil Spills

Oil spills are one ocean issue we forget about on a daily basis and it is only too late, once a massive disaster occurs, that we remember this enormous threat hanging over our blue planet. The recent oil spill in Mauritius has brought the fragility of our oceans back into the mass media and subsequently our minds, sparking massive protests across the world. So what exactly happened in Mauritius, what are the environmental impacts and how can we prevent incidents like this happening again in the future?

On the 25th of July 2020, the Japanese operated ship MV Wakashio ran aground off Mauritius, an island nation lying in the Indian Ocean west of Madagascar. Twelve days after the ship hit rocks, it began spilling heavy fuel oil into the surrounding ocean with 1,000 tonnes of oil now forming a slick spreading over 15 kilometres of near shore waters. Whilst 15 kilometres may sound fairly small in the grand scheme of things, the oil is leaking onto a 100,000 year old pristine coral reef filled with diverse and rare creatures such as green turtles. The oil slick is threatening to breach the Blue Bay Marine Park whilst the country’s mangroves, which are designated as being a site of international importance, have too been covered in this toxic substance. Large waves and strong winds shortly after the grounding meant the clean up operation was made increasingly difficult, giving the oil time to seep up rivers and float above delicate seagrass beds which are home to enigmatic seahorses. As a result of the damage, the government declared a state of emergency soon after the ship began leaking fuel oil, yet the damages seem to be getting increasingly worse.

The front half of the vessel was purposely sunk as part of the clean up programme, an action filled with controversy as the long term impacts of this could lead to even more devastation. Whilst the sunken remains do not hold any harmful substances, the skeleton of the ship can still pollute the surrounding water for years to come with flakes of toxic paint and chunks of rust. Within days of the ship being sunk, 50 dolphins and whales washed up dead on the beaches which were known as paradise only a few weeks before. The death of marine mammals in the case of an oil spill is not unusual, however the speed at which these individuals died after the accident is strange, leading to scientists calling for additional investigations to find out exactly what the impacts of this specific incident are. These species of mammal are protected, making it a crime in itself to kill them. To make matters worse, the Japanese insurance company for the vessel has called in international consultants, leaving the local Mauritian scientists fenced off from their own beaches and in the dark about the state of their once thriving ocean environment. Due to all these factors, mass protests have been sparked not only across Mauritius but also in cities around the world which are filled with their own Mauritian communities. These local people have lost their income from tourism and fishing, their important seafood supply and now potentially an enormous part of their ecological and cultural heritage.

If you look at some datasets, the number of oil spills appear to be falling, with the number of incidents spilling more than seven tonnes of oil decreasing from 80 spills per year in the 1970s to just an average of six today. Yet when you look more closely, the few incidents we have today often involve much larger quantities of oil than in the past due to the increasing size of ships. It also doesn’t take into account the impact of spills under seven tonnes, which actually account for an astonishing 80% of all ocean oil spills and so add up to a significant part of the problem. Not only can oil leak from grounded ships but small leaks occur often within harbours whilst one of the world’s most famous spills came from the Deepwater Horizon offshore oil rig in 2010.

No matter how much oil is spilt, the ocean inevitably suffers in some way. Strangely however, a small spill can sometimes cause more damage than a large one depending on certain factors such as prevailing winds and currents and whether the oil was spilt out in the ocean or in a nearshore ecologically sensitive area such as a coral reef or the Arctic. In fact, one of the most environmentally damaging oil spills occurred in Arctic waters in Alaska in 1989. The remote location, freezing temperatures, icebergs and stormy sea conditions made the clean up operation incredibly difficult, leading to 2,100 kilometres of coastline being impacted, with 2,000 sea otters and 250,000 seabirds sadly dying as a result. One of the most common environmental impacts of an oil spill is that creatures such as seals and seabirds get oil on their skin. Oil then strips their skin or feathers of their specially evolved waterproof layer which keeps these animals warm in cold seas and cool in high temperatures. Often, seabirds try to remove the oil from their wings by using their beak to preen themselves, yet sadly this often worsens the problem as they end up ingesting this toxic substance. Many other animals in the food chain accidentally ingest oil too, and these chemicals remain in the bodies of prey, resulting in the top ocean predators such as killer whales having a high level of toxic substances in their stomachs. Over time, this can lead to suppressed immune systems and lower fertility. Even right at the bottom of the food chain, small molluscs, corals and crustaceans filter feed tiny chemicals when they intake a gulp of water. These impacts are exacerbated depending on where the oil spill occurs. If oil spreads to important feeding and breeding grounds, or in the case of Mauritius to busy whale migration routes, many more creatures are likely to be impacted. If oil didn’t cause enough trouble in the sea, it can also give off fine particulates which contribute to toxic air pollution, harming creatures such as birds which live on the shoreline; the unique pink pigeon in Mauritius is now threatened by this invisible enemy.

So how exactly do clean ups happen after an oil spill? Mauritius has taken an unusual response to protect their unique coastline and communities around the island spent a whole weekend handcrafting an astonishing 80 kilometres of ocean booms. These booms are designed to act as a fence to prevent oil floating further out to sea; from there, scoops are used to collect the oil from the water, using a technology not dissimilar to a hoover. The difference in Mauritius was that the booms were homemade from the plant leftovers of their sugar cane processing industry. Instead of using a mechanical scoop, locals gathered together clothes and even cut off their own hair and used both materials to act as absorbents to soak up the oil from the sea surface, an ingenious idea which highlights their dedication to the ocean. The local community decided to take this decision as they were unhappy with the slow moving response of their government, despite many options for clearing up oil being available. Depending on the type of oil and the extent of the spill, the surface slick can be burnt up to remove it from the water, however this contributes to toxic fumes. Chemical dispersants provide another imperfect solution as whilst again they are designed to break down oil, they add another type of pollution to our oceans with their use being banned in several countries. An alternative would be to use specific microorganisms including bacteria, fungi and algae to degrade the petroleum products and whilst this is a natural process, it is often quite slow, not a characteristic that is wanted in an environmental emergency.

So it seems that prevention is once again better than the cure. Already areas such as the Arctic have strong measures in place to prevent an oil spill in one of the world’s last remaining great wildernesses. Tankers that pass through its icy waters must be double hulled, allowing a layer of protection in case one hull cracks open. Large ships are also escorted through narrow, dangerous and shallow sections as those with local knowledge provide international vessels with a safe route through the rocks and icebergs. Other measures include the electronic tracking of ships, regular checks to ensure vessels are in good condition and all local countries have a well-practiced response in place, with resources and people ready to jump into action at any second and all of these measures can, and should be, implemented around the globe. On dry land, scientists have also set to work to help make a difference to future oil spills. Already, new buoys have been designed, with each one containing a small sensor which remotely monitors the coastline, helping detect if oil enters the area before sending a signal back to a human sat behind a computer monitor. The buoys can even detect which type of oil is spilt, allowing a quick, effective response to be put in place. Meanwhile, large sponges made from polyurethane foam and coated in silane have been developed by other innovators. These enormous sponges can be dragged across the sea surface and along the way they absorb nine times their weight in oil whilst cleverly leaving the water behind. Once fully saturated, these sponges can be wrung out and the oil reused, saving the both the ocean and waste.

Whilst these ideas are clever, it is unfortunately too late for these measures in Mauritius. Instead surfers and water lovers from around the world are signing a petition to ensure the local people gain the fair compensation they deserve due to the disruption the accident has caused to their economy and way of life. Yet no amount of money can bring back the ocean ecosystems they stand to lose and this is why we need to call for greater preventative measures and quicker, more effective responses to oil spills, a threat looming over our oceans with each ship that sets sail.

By Neve McCracken-Heywood