Researchers continue to theorize as to why orca whales have been ramming boats off the coast of Spain and Portugal this year.
As of late May, 24 incidents had been reported to Spain's maritime rescue service.
But DFO whale researcher Jack Lawson said boat crews probably shouldn't be concerned about orcas found in western Atlantic waters, because it's been happening near Spain for about four or five years.
"There's a couple of theories for it. One is that because they're smart, playful animals anyway, that it might just be sort of a fad amongst a group of whales. They've learned to have some fun with, mainly it seems to be, rudders of smaller vessels, especially sailing vessels," Lawson said.
"And the other hypothesis was that perhaps one of the killer whales had been injured some way in the past by a boat and was kind of taking out their bad experience on some of the vessels it encounters."
Lawson said in his experience orcas seem to be the whale species most interested in human activity
"It's pretty exciting," he said.
"You can watch them, watch the eyes move, they manoeuvre around if you do something in the boat. If you lean over the edge or pick up a piece of equipment, you can see them react, they get more interested."
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There are more orcas in western Atlantic waters than in the Mediterranean.
Lawson said there are a few dozen near Spain and Portugal but several hundred on this side of the Atlantic spread over a larger area, from the northern tip of Labrador all the way to Nova Scotia and the U.S. border.
"I would say they're regular. Every year we get a handful of sightings close to St. John's, and as well fishers off shore in the Grand Banks report them fairly regularly."
Whether orcas will act the same in waters near Newfoundland and Labrador this year remains to be seen.
Lawson said there has been no indication of such activity to date, except for one report in 2008 when an orca bumped a vessel.
"Nothing had been hurt and the whale moved away. Whether that was the whale smacking them out of play, or misjudged, I'm not sure," he said.
Lawson said people shouldn't approach marine mammals within 100 metres anyway. Any boaters who come across orcas in N.L. waters this summer should keep a steady speed and direction, and if the killer whales begin to be a cause for concern, boaters should head for shore.
"It seems that when these boats get close to shore these whales break off and head out to sea. That's usually the safest thing to do."