"There is no evidence that Gladis and her pod are attacking humans or that they intend to harm people at all."

"In fact, wild orcas have never been seen treating people as prey. They do, however, have a thing for 'fads,' where they take up behaviour that has no obvious benefit. One famous example involved a female in the Pacific northwest who, in 1987, was seen wearing a dead salmon on her head. The trend spread. Other orcas across Puget Sound were soon spotted with their own 'salmon hats.' And then, as abruptly and as mysteriously as it started, the fashion fizzled out. Other orcas have been seen draping kelp over their backs or heads.... To scientists, the behaviour with the boat rudders looks similar. After wrenching one free, Gladis and her companions tend to bat it around for a while, then lose interest and swim off.... One [researcher] believes the orcas see the yachts, with their long detachable rudders, as 'giant toy dispensers.'"

From "Orcas blamed for yacht attacks are speaking their own language/Scientists studying killer whales linked to hundreds of encounters with boats near Gibraltar have discovered that the pod communicates using a unique dialect" (London Times).