Orca find easier way to get lunch

By Tyler Cowen

The orcas will wait all day for a fisher to accumulate a catch of halibut, and then deftly rob them blind. They will relentlessly stalk individual fishing boats, sometimes forcing them back into port.

Most chilling of all, this is new: After decades of relatively peaceful coexistence with cod and halibut fishers off the coast of Alaska, the region’s orcas appear to be turning on them in greater numbers.

“We’ve been chased out of the Bering Sea,” said Paul Clampitt, Washington State-based co-owner of the F/V Augustine.

Like many boats, the Augustine has tried electronic noisemakers to ward off the animals, but the orcas simply got used to them.

“It became a dinner bell,” said Clampitt.

John McHenry, owner of the F/V Seymour, described orca pods near Alaska’s Aleutian Islands as being like a “motorcycle gang.”

“You’d see two of them show up, and that’s the end of the trip. Pretty soon all 40 of them would be around you,” he said.

A report this week in the Alaska Dispatch News outlined instances of aggressive orcas harassing boats relentlessly — even refusing to leave after a desperate skipper cut the engine and drifted silently for 18 hours.

These are not Coasean orcas, or are they? And sperm whales are now in on the act:

Fishing lines are also being pillaged by sperm whales, the large square-headed whale best known as the white whale in Moby Dick.

“Since 1997, reports of depredation have increased dramatically,” noted a report by the Southeast Alaska Sperm Whale Avoidance Project.

A remarkable 2006 video by the Avoidance Project captured one of the 50,000 kg whales delicately shaking fish loose from a line. After a particularly heavy assault by sperm whales, fishers are known to pull up lines in which up to 90 per cent of the catch has disappeared or been mangled.

http://marginalrevolution.com/marginalrevolution/2017/06/orca-wars-escalate.html

Link at maggiesfarm.