Thursday, 7 January 2016

Rare Killer Whale Dies After Becoming Entangled in Fishing Gear

Scottish bird photographer John Bowler received an unwelcome text on Sunday from a farmer who had stumbled on a killer whale that had washed up on the coast of Scotland’s Isle of Tiree.
“I was expecting to see it when I went, but it was still a great shock and shame to see such a magnificent animal still in good shape dead on the shore,” said Bowler, who has been the head officer for the Royal Society for the Protection of Birds on Tiree the past 14 years. “A great pity that the first-ever killer whale I should see should be under such circumstances.”
The 20-foot killer whale was identified as Lulu, a member of the rare resident population of orcas that live off Scotland’s west coast. According to the Hebridean Dolphin and Whale Trust, there may be as few as eight individuals remaining in the West Coast Community, which has not produced calves since the conservation group began studying the pod in 1992.
Andy Foote, a cetacean specialist with the trust, said the distinct shape of Lulu’s eye and saddle patches were used to ID the orca and matched photos taken of the animal off Scotland’s Isle of Skye in 2014.
“It is very sad to lose a member of this unique group,” Foote said in a statement on Monday.
An autopsy completed Wednesday by the Scotland Rural College’s Marine Animals Strandings Scheme found deep scarring and wounds around Lulu’s fluke, an indication that the animal’s tail was most likely wrapped in rope or other fishing gear.
RELATED: The Unseen Slaughter Under the Sea
“By the time we had heard of her stranding and travelled to Tiree, she had been dead for four days, so much of the internal organ structure had been lost,” Andrew Brownlow, the strandings team’s director and a veterinary pathologist, wrote on the group’s Facebook page. “Nonetheless we found convincing evidence that she had become chronically entangled and this was the most likely cause of her death.”
There were no ropes or fishing gear present when Bowler discovered the animal, so no determination of whether the wounds were caused by active fishing gear or abandoned equipment, often called “ghost” gear, could be made. If the ropes wrapped around her tail were attached to larger gear, it would have made normal swimming and foraging activities difficult. Lulu and her pod are known for hunting large prey such as dolphins and seals, which requires powerful swimming and agile maneuverability.
“We suspect the animal had been entangled for several days,” Brownlow wrote. “She hadn’t fed recently but had swallowed a large amount of seawater, most likely as she eventually succumbed to the entanglement and drowned.”
Lulu is the first killer whale the strandings team has encountered with entanglement scars, but the team reported an increase in entanglements in other whale species over the last year.
“In Scotland, we've only had 13 killer whale strandings in the past 20 years, of which only 8 were examined in any way,” Brownlow wrote in an email to TakePart. “There does seem to be an increase in entanglement [for other cetaceans] over the past few years, but we need to properly analyze the data to see if this is a real trend.”
With Lulu’s death, only three females remain in the West Coast Community, and chances of their survival are decreasing, according to Foote.
“It’s probably too late to save this group,” Foote said in 2011. “I do believe that they will become extinct in our lifetime which is very regrettable since not many people even know that such a distinctive group of killer whales exist just off our coast.”
At the time, he blamed runoff from contaminants such as fire retardants, pesticides, and manufacturing chemicals for polluting the whale’s feeding grounds and poisoning mothers and their calves.

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