Orcas are ramming boats and harassing yachts near Portugal and Spain, from Galicia to the Strait of Gibraltar. It is baffling to scientists why killer whales are damaging sailing boats.

Worrisome Encounters

The past couple of months have seen sailors in areas from northern to southern Spain, sending their experiences distress calls. Two of the boats had parts of rudders lost, and at least one crew member sustained bruises from the ramming impact. Many ships had severe damage.

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Latest Cases

One of the latest occurrences was last Friday afternoon off Spain's northern coast, particularly A Coruña. The company Halcyon Yachts was bringing a 36-foot yacht en route to the UK. According to Halcyon Yachts managing director Pete Green, an orca proceeded to ram the stern a minimum of 15 times, losing its steering. It had to be towed to port from the damage.

At approximately the same time, radio warnings announced sightings off the city of Vigo. It is near the places where two collisions occurred recently.

Last August 30, a French boat sent a distress call to the coast guard, saying it was being attacked. Later that same day, the Spanish Mirfak naval yacht was also struck by orcas, losing part of its rudder in the process.

Orcas' Strange Behavior

Orcas, the largest dolphins, are social and highly intelligent. The scientists who study them in the area found them curious; they usually closely follow boats and interact with their rudders. However, they have not been known to harass them before.

Maritime authorities of the Spanish government were advising boats to maintain distance. In July to August, there was a pod, maybe more, who keep pursuing ships in the area, which scientists found unusual and of significant concern.

Scientists say it could be an indicator of stress.

"Orchestrated" Behavior

Last July 29, of Cape Trafalgar, a 46-foot delivery vessel was being crewed by Victoria Morris when a group of nine orcas surrounded it and rammed its hull for more than an hour.

The mammals spun the vessel around up to 180 degrees, which disabled its engine and broke its rudder. All the while, they were communicating through loud, whistling sounds. Morris says the move felt "totally orchestrated."

Early that same week, a boat in the same area had an encounter that lasting 50 minutes. According to the boat's skipper, the ramming had such a massive force that it almost dislocated a helmsman's shoulder.

Various Attacks

A similar thing happened the night before, when the 40-foot yacht of British Kevin Large and Beverly Harris was suddenly halted and spun many times. Harris said he felt that the boat was raised a little.

Early that same evening, Nick Giles heard a loud bang and then found his steering wheel disabled and turned, spinning his 34-foot Moody yacht 180 degrees. The pushing went on for a quarter of an hour; Giles also felt his vessel was lifted.

According to orca researcher Ruth Esteban, it is likely that only one orca pod is responsible.

Morris wants to take up marine biology and is interested to learn about the vulnerable orcas in the area, but still wants to stay at a distance. Their damage and trauma to boats and yachts in Galicia, Spain, and the Strait of Gibraltar, particularly her first-hand experience, got her jumpy.