Sprinkling sand ‘deters orcas’ advises Cruising Association
As we have mentioned previously, and has been reported widely on social media, a number of sailing yachts have been the subject of rudder attacks by pods of aggressive killer whales in recent months. One of our clients, a 25m sailing yacht, was also attacked in the Strait of Gibraltar on their way to the Mediterranean.
Now, the Cruising Association has shared advice that throwing sand into the water can create a haze that disrupts orcas’ echolocation ‘vision’, as the sand varies the density of the water, causing an acoustic mirror effect. Sprinkling sand is a harmless tactic that effectively obscures the rudder from sonic view, the report suggests.
More advice comes from the Spanish transport ministry, which advises cruisers to “navigate as close as possible to the coast” and, in the event of an interaction, motor away as fast as possible towards shallower waters until the orcas lose interest. Scientists have undertaken many runs with orcas at sailing yacht speeds but using motorboats, reporting that the orcas did not follow for long and that little rudder damage was incurred.
This unofficial website is tracking and mapping killer whale activity in the vicinity of the Strait of Gibraltar.
We can’t vouch for accuracy or completeness, but for details, visit https://www.orcas.pt/