An Italian-based NGO hopes its “Save the Whale” campaign will get cruise liners, shipping operators and fishing fleets on board to prevent the mammals from colliding with their vessels.
Shipping is doubling every decade and, according to the World Sustainability Organisation (WSO), at least 20 000 whales were killed in 2020, a figure that has quadrupled in the past 20 years.
The WSO will reward shipping operators who are committed to implementing measures to prevent ship strikes. Their vessels will be recognisable by the “Friend of the Sea” logo and “each of us can contribute to the protection of whales by choosing those certified operators”.
The NGO said maritime operators, ship owners and governments must implement measures to prevent lethal collisions, including using thermal cameras for the recognition of cetaceans (whales, dolphins and porpoises) and online sightings reporting systems, and where appropriate, sea route changes.
There is a risk of continuing declines even if only a small number of ship strikes occur a year, the WSO said, noting that most dead whales are deposited at sea and only 10% are washed ashore.
For every incident that is observed and reported, there will be many others that are unseen, making it hard to assess the conservation implications of ship strikes, according to the International Whaling Commission.
There is no universal solution to the problem of ship strikes, the commission said, adding: “For now, the most effective ways to reduce collision risk is to keep whales and ships apart, and where this is not possible, for vessels to slow down and keep a lookout.”
Cetaceans face several threats to survival, said the WSO’s marine biologist Roberto Lombardi. “Most are human-induced or amplified by human activities: whaling, ship collision, ocean noise, pollution and climate change. While difficult to quantify, ship collisions are known to be major threats to whales.”
The severity arises from three main factors.
“First, the overlap between areas with a high density of whales and ships creates areas with high probabilities of encounters. Second, collisions that do occur have a high probability of whale mortality. Indeed, at a ship speed of 12 knots, there is a 50% probability of whale mortality following a collision event,” Lombardi said. “This probability reaches respectively 70% and 90% at 14 knots and 18 knots. Third, the risk of collision also has increased over the years as a result of increased ship traffic. Combined, these factors contribute to an ever-growing threat to whale survival.”
Separating shipping lanes from areas of highest whales’ presence is the optimal solution, but not easy to implement, at least in the short term. “Slowing down to a speed, normally 10 knots, which would allow whales to avoid the ships, is a measure which can dramatically reduce lethal strikes and also reduce noise pollution,” Lombardi said.
Els Vermeulen, of the University of Pretoria, agreed that more mitigation measures are needed. “As the populations of whales visiting South Africa’s coast are increasing, this will inevitably lead to more cases of ship strikes. Think, for example, about the large super groups of humpback whales that visit the West Coast each year.”
Between 1999 and 2019, roughly 11% of whale strandings in local waters related to a ship strike, she said. “These collisions in local waters may be a growing threat because of population increases and the Operation Phakisa initiative of the government, but it is at this point definitely not a major conservation concern on a population level.”
In 2020, a global scientific review of vessel collisions with marine animals by Nelson Mandela University and the Endangered Wildlife Trust found that at least 75 marine species, ranging from whales to dolphins, sharks, sea otters, seals, penguins and sea turtles, were recorded as being killed by collisions with ships — and that collisions between marine animals and ships occur far more regularly than previously thought.