The last-ever killer whale show at California's Sea World happened without fanfare this week, but for the orcas living in captivity, freedom is not on the horizon.
Now new research is looking at ways to keep orcas sane while they live out their days in zoos and entertainment parks.
The affect of captivity on these intelligent and sensitive creatures was brought to life in the startling 2013 documentary Blackfish, that showed how harsh capture and conditions led orca Tilikum to kill his trainer.
The film spurred protests worldwide to have the animals released and in 2014, a California lawmaker introduced a bill to ban live performances and captive breeding of killer whales in the state. Those already at Sea World will live out their lives.
Today two University of Galsgow researchers have devised methods to provide new stimulation to orcas in captivity, including a way for them to 'phone home' to wild orcas, as well as games designed to mimmic their environment.
To show just how intelligent orcas are, the study shares a shocking Australian story of intelligence -- and murder:
In the late 19th and early 20th centuries, Australian shore-based whalers were alerted to the presence of Humpback whales Megaptera novaeangliae by a male Killer whale called 'Old Tom', who attracted the whalers' attention by performing at the whaling station.
The whalers followed the Killer whale to the Humpback whales, which they slaughtered, giving the Killer whales access to the tongues and lips of the Humpbacks to feed on.
The study argues that vocal communication is important for pods of killer whales, and zoos could facilitate something akin to that by using satellite-communication systems to hook them up long distance with other zoos and wild listening stations.
The researchers said it had been shown different killer whales had different dialects.
"So the ability of Killer whales with different dialects to learn how to communicate with each other is highly probable, and would provide fascinating opportunities for research into vocal communication,
vocalization and vocal-control learning in cetaceans," the study said.
Around the world, there are still killer whales in captivity in The U.S., Russia, Spain, Japan, France, Canada and Argentina.
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