VOR - Sailing Safely With Whales And Dolphins
Sailing Safely with Whales and Dolphins
Advisory for sailors regarding the risk of collision with marine animals at sea to promote safety for both whales and sailors.
The Facts, Evidence and Expert View
(a) Collisions between sailboats and whales seldom occur but there is enough anecdotal evidence to support precautions in order to minimize the risk both to whales and to the sailors. Fast moving ferries and container ships are a known source of whale collisions, even though these events are underreported, in part because these ships can be ten times the size of even the largest whale so the impact of the strike goes undetected. By contrast, sailboats are usually much smaller, weighing a fraction of a mature blue, fin, right or humpback whale. In 2005 the South African entry to the America´s Cup, the “Shosholoza” reported a whale collision off Cape Town and in 2007 the German “Albatros” collided with a whale during the transatlantic Blue Race. A high speed whale collision during a sailing race not only puts whales at risk, but can result in serious injury or fatalities to sailors and will likely damage the boat, eliminating it from the race. The whales most often reported in collisions are fin whales, humpback whales and highly endangered North Atlantic right whales.
(b) Despite (a) above, any whale or dolphin, as well as sea turtles, sunfish, basking sharks and other fish and marine mammals that spend time at or near the surface, can be the source of a collision. Bow-riding dolphins are normally not a problem but at times dolphins can be caught resting or completely preoccupied by feeding.
(c) Collisions fatal to whales occur mainly at boat speeds of 14 knots or greater. At 10 knots or less, mortality resulting from collisions is much reduced.
(d) The evidence regarding acoustic deterrents (putting loud sounds in the water) for large whales is either that the sounds place the whales at increased risk near the surface as they try to avoid the sound, or that they will approach sound devices, demonstrating curiosity. Loud noises also have the possibility to disturb whales and dolphins. The widespread view among marine mammal scientists is that acoustic deterrents are not a good idea.
Humans share the ocean with whales and dolphins. For us the ocean is a source of food, transport and recreation but for whales and dolphins it is their home. Therefore, we must take measures to reduce the risk of collisions. This is particularly important when boats are travelling fast and at night when observers are of limited use.
Look, Listen, and Avoid
• Post an observer at the bow who can identify the presence of whales (distant dorsal fins, flukes, spouts) as well as their behavior. Feeding and socializing whales as well as calves are at particular risk of collision. Aerial surveys can be useful to detect the presence of whales in real time over a wide area.
• If a hydrophone is available, listen for whale sounds which may be picked up at a range of 1 to 10 nm but remember, sometimes whales are quiet. A combination of visual and audio approaches, as well as aerial surveys covering important habitats of the most vulnerable whale species (fin, humpback and right whales), would be ideal.
• If whales are seen or heard while sailing, keep a wide berth. If possible, reduce speed to 10 knots or less. (The specific directive for whale watch boats using sails is in fact to drop the sails in close proximity of whales and use auxiliary engines to maneuver safely.) Best of all, consult beforehand on your exact route in view of the seasonal presence of whale concentrations and avoid these areas if possible. If these areas must be transited, do so during daylight and consider the additional directives provided in this document. Some marine protected areas or whale sanctuaries have special zones or preferred shipping lanes where whale collisions may be less likely. A precautionary approach to reducing risk means taking all of the above into consideration before leaving the dock.
If you have experienced or witnessed a collision between any boat and a suspected whale, dolphin or other animal, please let us know. There may also be requirements, such as in US waters, about reporting a collision. It is only by learning more about each circumstance that we can help reduce the risk of collisions in future.
— WDCS, the Whale and Dolphin Conservation Society