Ocean transit is vital, but it can leave its mark. What more could the shipping industry do to help preserve marine life?
Carriage by sea is the least environmentally damaging form of commercial transport, and when compared to land-based industry it is a minor contributor to pollution. However, it certainly does literally leave its mark, as ship strikes are recognised as a serious conservation and welfare problem for a great many whale populations. It is estimated that thousands of whales die every year from ship strikes, and this is on top of the other risks that these mammals are facing, including habitat loss, noise, climate change and pollution.
The number of whale deaths in vessel-related incidents is difficult to estimate and they are probably very significantly under-reported, but some studies say that 10-20% of whale deaths are caused by ship strikes. Furthermore, other threats to marine life – and especially underwater noise – have increased dramatically with greater vessel size, speed and numbers.
The whole industry and each seafarer within it must make the effort to listen to the quiet mammals and other animals and also plants beneath the ocean surface, and help to preserve marine life. While in some places numbers are increasing, currently it is estimated that there are only about 15,000 whales left in the world. Separating shipping lanes from whale habitats and migration routes is obviously the most effective option, but where that is not possible reducing vessel speed can also help protect whales from strikes.
But ensuring that all mariners are actually aware of ship strikes and the related issues is also key to tackling this problem.
When a whale comes up in the path of a ship, quick determination of its direction of travel will help those on the Bridge to identify the best course of action. Steering behind the whale is often the most effective course, and even a small (but immediate) reduction in speed can make the difference between a strike and a near miss. Research suggests that if the average speed of the global shipping fleet was to reduce by around 10% there would be a 50% reduction in the risk of collisions with whales, and furthermore a 40% reduction in underwater noise from shipping.
Underwater radiated noise is indeed a major concern, and the further measures that ship owners can take to meet IMO greenhouse gas reduction targets can also help with that.
In view of the energy efficiency ship index (EEXI) which came into effect on 1 January 2023, as well as reducing speed there are measures that focus on improving the water flow around the hull and into the propeller. This reduces the pressure differential across propellers, with the cumulative effect of lessening propeller cavitation and thus tackling a major source of noise. Both legally and also ethically it is the responsibility of seafarers, ship owners, shipping companies and indeed all industry stakeholders to protect underwater life, and small changes in practices can dramatically reduce harm for whales. Just one example is a small change in shipping routing in the Mediterranean and also the Indian Ocean around Sri Lanka, where there are endangered sperm whale populations. What might involve just 10 more nautical miles per voyage can very substantially lessen and maybe even eliminate a risk of whale strikes.
Moving on to other aspects, key issues are establishing sound criteria for the cleanliness of all water that is pumped back into the sea, better tackling biofouling growth, CO2 emissions and of course avoiding marine casualties, following which oil pollution will very seriously affect the beautiful living world beneath the surface. It is known that marine organisms growing on a hull increase drag and can reduce a vessel’s fuel efficiency by as much as 35%, obviously leading to higher fuel bills and more CO2 emissions. So it is plainly important to remove the growth at least every couple of years. However, a number of countries and regions have rightly put biofouling management high on their agenda, as hull cleaning other than in dry dock can transfer invasive species to local marine environments. So it is vital that the debris is captured, and to combat this problem and also provide clarity and quality assurance to ship owners, ports and government authorities, BIMCO and the International Chamber of Shipping have published the first industry standard on hull cleaning while the vessel is still in the water.
Also, the shipping industry gradually decarbonising and new sustainable fuels being adopted can make a very important contribution to environmental integrity, and it has also been calculated that a worldwide 27% reduction in sudden manoeuvres and an 18% drop in speed delivers an annual lessening in CO2 emissions of over 66,000 tonnes, greatly helping towards sustaining the environment and supporting compliance with the new carbon intensity indicator (CII) provisions.
There must also be increased focus on promoting the sustainable use of our oceans and marine resources, as well as having cleaner seas, and LNG, LPG, methanol, biofuels and hydrogen are among the alternative fuels and new technologies increasingly used to reduce CO2 emissions, which of course ultimately, and adversely, affect marine life.
Biofuels are derived from primary biomass residues, which are converted into liquid or gaseous fuels, and it looks like the most promising ones are biodiesel and LBG, or liquified biogas. Biofuels still need large scale production, but for example a blend of 30% hydrotreated vegetable oil biofuel and 70% MGO in dual fuel LPG vessels has registered a 20% emissions reduction when compared to even very low sulphur fuel oil.
Shipping is constantly adapting to ensure that our seas are looked after, as an integral part of how the industry operates and delivers for society, cargo owners, charterers and all parties in the marine supply and demand structure. By first understanding and then responding to the need to limit its environmental impact, the maritime industry has been working towards ensuring that a great many types of pollution are reduced. We should all pledge to continue to strive together to help stop pollution, ship strikes and other causes of harm to marine life and the ecosystem, and further promote awareness and practise new technologies to help achieve that.
2/E Naznin Shamim – Hafnia Phoenix
