12 Aug 2016

Life and Death in the Salish Sea

By Claire Eamer
An orca, or killer whale, in the Salish Sea near Nanaimo.
Alan Daley photo

My husband, Alan, and I live on a small island in the Salish Sea, the body of water that lies between Vancouver Island and mainland British Columbia. Our place is on a low cliff overlooking the sea, and we spend a lot of time watching what goes on out on the water. That's what Alan was doing one afternoon early in May this year when he spotted a pod of orcas (killer whales). Here's his description of what he saw.

Alan speaking now:

Whales mill about a sea lion, its flipper visible in the turmoil.
Alan Daley photo
I discovered orcas just below off the cliff. They were milling about, and I noticed there was a sea lion in their midst. It was just lying still in the water for the most part. 

The whales repeatedly passed close to it, sometimes passing under it and flinging it partly out of the water. 

A sea lion tries to grab a breath, as killer whales attack it.
Alan Daley photo
Occasionally, I saw the sea lion put its head up and take a breath of air, but when it showed any signs of life, the beating intensified. 

There were a total of six whales. Two large males mostly hung out upwind/seaward of the action, and slapped the water occasionally with their tails. The smaller whales did most of the work. 

They seemed to have a strategy of exhausting the sea lion through physical beating and preventing it from breathing by huge splashes that sent it underwater. 

The injured sea lion is tossed into the air again.
Alan Daley photo
After I had watched for more than an hour, they headed off north with the sea lion seemingly moving without making any swimming motions. A couple hours later, I saw the body drift back down past the cliff.

Alan contacted the Orca Network to report the sighting and  included a couple of his photographs.

Howard Garrett of the Orca Network showed the photos to an expert, Dave Ellifrit of the Center for Whale Research. He identified the two large males as T19B and T19C, members of a pod of Bigg's killer whales -- also called transient killer whales.

Bigg's killer whales live in small family groups led by a female. They prey mainly on sea mammals, hunting up and down the coast of northwestern North America.

The kind of behaviour Alan watched might have been hunting lessons for young members of the pod or simply hunting practice. Steller sea lions are roughly the size of a bear and have formidable teeth and claws, so buffetting them with waves and tail-swipes keeps the whales safely away from the sharp bits.
Whales circle the sea lion, now seriously injured or dead. Alan Daley photo
The Salish Sea is also home to resident pods of killer whales. The resident whales live very different lives -- eating fish, mainly salmon, rather than sea mammals. They have different behaviour patterns, different dialects, and different cultures, and the two killer whale cultures seem to have very little contact with each other.

There's a wealth of information about both resident and Bigg's killer whales on the Orca Network website. And if you happen to be near the Salish Sea and spot some killer whales, let the network know. Every bit of information helps us understand and protect these amazing animals.

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