By: Kira Coley
Hidden under the rolling waves, Earth’s giants glide up from the deep ocean. Although whales spend most of their time submerged underwater, they must breach the ocean’s surface to breathe. This simple act of life makes them especially vulnerable to ship strikes, which are often fatal. In the north-east Atlantic, it is the fin whale that is most at risk of collision with the growing swarm of traffic flowing relentlessly over their submarine home. On a global scale, the incidence of ship strikes is thought to be largely underestimated, with many going unreported. This year, Europe’s leading whale and dolphin conservation charity, ORCA, is working in conjunction with the UK’s Brittany Ferries to further understand how whales respond to large vessels. Through pioneering research, they strive to provide evidence that can help the industry discover much-needed solutions for the problem of ship strikes—a deadly problem that is impacting whale populations across the globe.
Fin whale surfacing. Although whales spend most of their time submerged underwater, they mustbreach the ocean’s surface to breathe. Photo credit: ORCA.
Killer Whales spotted from a Brittany Ferry. ORCA records all of their sightings from on-board Brittany Ferries in a blog at https://brittanywildlifeofficer.wordpress.com. Photo credit: ORCA.
The Bay of Biscay is one of the busiest shipping routes in the world. The area also harbours a high number of fin whales each year between April and October—over 5,000 out of the 17,335 estimated in the whole North- East Atlantic—putting these animals most at risk.
It is almost impossible to understand the true extent of how many whales die each year from ship collisions. If an accident is fatal, baleen whales sink to the bottom of the ocean and only sometimes resurface. There are also vast numbers of live sightings where animals are scarred and injured, suggesting that ship strikes are not always fatal and perhaps more common than previously thought. In the Mediterranean Sea, for example, where whale collisions are a major issue, 40% of fin whales washed onto shore suffered ship strike injuries, while only 16% were reported to have been fatally killed by such collisions.
Strait of Gibraltar, Spain. 1 October 2010. A huge containership is crossing the street of Gibraltar (between Spain in Europe and Marocco in Africa). In the back are the mountains of Marocco. In the front there are some pilot whales. Photo credit: Jan-Otto.
Lucy Babey, head of Science & Conservation for ORCA, explains, “Some whale species are more susceptible than others, particularly baleen whales, which cannot echolocate. Those that are big, such as the blue and fin whales, or slow moving, such as right whales, are most susceptible. Juveniles also tend to be hit more often than adults, possibly because they are less spatially aware. Over 90% of whale ship strikes also seem to occur at continental shelf edges, where the seafloor depth dramatically increases. The shelf edge in the Bay of Biscay happens to be where highest numbers of fin whales are seen and where ORCA’s research and ship strike project will focus.”
According to the “large whale ship strike database” taken between 1975 and 2002, there were 292 records of ship strikes, an average of 11 per year. Fin whales were most frequently hit with a total of 75 individuals, an average 3 per year.
“These figures are minimum counts, however, and therefore the problem is likely to be on a much larger scale. In the Bay of Biscay, it is not known how many whales are victims of ship strikes. We are reliant on ships reporting a strike or near miss, and many ships are unaware that they have hit a whale, which is why it is so vital that we continue to research this area,” said Babey.
Oceans are becoming increasingly busy with a greater number of vessels that are both larger and faster. Research shows that longer ships at over 80 m pose greater ship strike risk as does increased speed. So, as this trend continues, the risk of ship strike increases.
Babey said, “Fin whales, along with other baleen whales, cannot echolocate. Some whale and dolphin species use echolocation in the form of clicks and echoes to build up a visual map of their surroundings. Therefore, it is thought that they misinterpret the ship’s proximity, either through visual or auditory means, which is what ORCA’s ship strike project aims to identify.”
“While the whales are likely to hear the ship’s engines, it is not clear with what accuracy they can pinpoint the direction and distance of these, contributing to some confusion when they surface and perhaps ‘see’ the ship when it is closer than they thought. These whales evolved in largely quiet, undisturbed oceans. And now due to human impacts, oceans are becoming increasingly busy with ships—something the whales seem to be struggling to adapt to. Juveniles have less experience avoiding ships, which may explain why this age group is most often hit.” Another theory is that the whales are often preoccupied with other behaviours, such as foraging, which takes their attention away from a nearby ship.
Global Efforts to Reduce Collision
Global efforts to reduce the incidence of ship strike have been tried and tested with varying success. Most strategies involve the enforcement of speed restrictions and altered navigational routes in areas known to contain a high concentration of whales; these have been very successful in some areas.
Researchers are now determined to continue the discovery of regions with high densities of whales. ORCA has identified the Bay of Biscay as one of these regions, especially in regards to fin whales. As a busy shipping route, the Bay of Biscay is an area of tremendous risk to whales colliding with the huge number of ships that pass through the bay—making this area a priority for ORCAs mission as they begin to investigate mitigation options.
In November 2011, ORCA and the World Society for the Protection of Animals (WSPA) came together to collaborate on a six-month project focusing on reducing ship strikes of large whales in the Bay of Biscay, the “Saving Large Whales” campaign. Following a workshop in April 2012 where representatives from industry, academia, and charities came together, innovative and pragmatic solutions were developed. New technologies have been trialled, and many bridge crews have been educated on the early detection and avoidance of whales.
Babey said, “Following on from ORCA’s ‘Saving Large Whales’ campaign, a pioneering research project commences in conjunction with Brittany Ferries this year to further understand how whales respond to large vessels and, in turn, provide evidence and solutions to the problem of ship strikes. A new theory suggests that although whales primarily navigate by sound, sight also plays a part. Little is known about whale reactions to vessels, particularly in the near-field and so this project aims to analyse fin whale’s spatial and respiratory responses to ships and at what distances any reactions occur.”
“From analysing these measured behaviours, hopefully it can be determined whether fin whales are responding to visual or auditory cues to avoid ships. By understanding their main cue source and predicted responses, shipping companies can be informed of appropriate collision- avoidance measures to lower mortalities.”
ORCA’s Wildlife Officers are on board one of Brittany Ferries. The Bay of Biscay is a great location for seeing whales and dolphins. Reaching depths of 4,000 meters, the Bay provides habitats for a range of different species. Photo credit: ORCA.
Manmade Hum of the Sea
It is not news that the sound of marine traffic can cause added stress to all marine mammals, often interfering with their abilities to communicate, forage, and navigate through their environment. But, in areas of high shipping density, acoustic overexposure from ships can leading to reduced hearing in whales.
“In some species, high-intensity noise pollution can cause severe discomfort, and there is evidence of burst ear drums in some cases if they are within in a certain radius of the vessel; this is mostly associated with submarines and military vessels,” explains Babey.
“There is also evidence that some mass stranding events have coincided with military sonar testing. Post mortems have revealed burst ear drums and symptoms of decompression sickness, when there are excess bubbles in the body. However, it isn’t just ship sound or strikes, but numerous factors contribute to mass stranding events, such as marine pollution, sick individuals, strong social bonds, navigational errors, and even underwater earthquakes.”
A Brittany Ferries ship arrives from France to Poole harbour in England.
Making Waves in Shipping Regulations
By looking at successes to date across the world, the main recommendations have been to reduce ship speeds in high-risk areas. Off the coast of California, USA, voluntary conservation agreements have not worked, and only 1% of vessels comply with speed restrictions. But off the east coast of the U.S., mandatory summer speed restrictions have been successful.
Although speed reduction might also apply to fin whales, each species is likely to react to vessels in a different way. As such, ORCA intends to take a species-specific approach to their future recommendations.
The 2017 ORCA Ship Strike project will be vital in understanding how fin whales in the Bay of Biscay respond to large vessels. From here, the charity, helped by industry partner Brittany Ferries, can inform policy, legislation, and the shipping industry to help reduce the risk of ship strike and develop appropriate collision mitigation measures. Through their novel research, if visual cues are found to play a major role in the whale’s recognition of a vessel and also in the whale’s decision-making process, new measures can be implemented.
Babey explains, “Implementing the right whale collision mitigation is never going to be an easy challenge. But if we can identify the primary sense whales use to identify a nearby ship and at what distances they take evasive action, hopefully, we can identify the best way to tackle this important issue. Any guidance that we develop for shipping companies is likely to take a while to come into action. However, working in partnership with Brittany Ferries on this project paves the way for other companies to also take action and will hopefully lessen such a challenge. This project will be an invaluable step towards the preservation of the endangered fin whale.”
Raising public awareness of the risk and impact of ship strike is important in addressing such issues. Babey recommends that all ship strike incidents and near misses should be reported to the International Whaling Commission. For readers based in the UK, if you find any live whales or dolphin strandings, call the British Divers Marine Life Rescue. And, any mortalities should be reported to the Cetacean Stranding’s Investigation Programme, CSIP.
