Saturday, April 10, 2010

Orcas! Transients feed on a Steller sea lion

My first orcas of 2010! We headed out on the Western Prince this afternoon optimistic about an earlier sighting of some Ts (marine mammal feeding transient orcas). Another boat relocated them shortly before we got into the area and we picked them up about a half mile south of Bird Rocks in Rosario Strait, a little ways off Lopez Island.

The initial report was of three whales, but it soon became apparent there were more than that. The setting was perfect as they surfaced several times in front of us with Mt. Baker in the background:



There were about five or six whales in the main group, with the most distinct one being the big male T87, who is at least 47 years old. He has a big rectangular-shaped notch out of the top of his fin, with another smaller notch right below it. Here he is surfacing with a juvenile whale in front of him:


Also in the group was T80, an older adult female, the only other whale I was able to definitely identify. But based on the whales they usually travel with according to the ID guide, this may be the 30 year-old female T90 and her four year-old offspring T90B:


All the whales were hanging around in one spot doing a lot of circling and hanging at the surface. We didn't see them make a kill, but it certainly seemed like feeding behavior. Another clue was the several dozen gulls that were circling over the whales, and occasionally touching down on the water, apparently feeding. Our passengers were using the gulls to help figure out where the whales were next going to surface, as their literal birds-eye view helped them to keep better track of the whales underwater than we could! Hmm....what was going on?


Soon it became apparent what was happening when I saw this whale pushing something at the surface. A closer look revealed it was the brown hide of a Steller sea lion - check out the photo below, just to the right of the whale. In several of my other photos you can see the sea lion (already dead on our arrival) at the surface, or pieces of meat in a whale's mouth. They were feeding on a recent kill, and sharing the food among the group.



Steller sea lions are not easy prey to take down. The males we have hanging out in the area this time of year are behemoths with very sharp teeth that weigh up to a ton. Some notches and scratches on transient whales are undoubtedly inflicted by defensive sea lions. They're too much for a single orca to handle, so it definitely takes some expert teamwork among a group of Ts to kill one. It's just another example of how intelligent these animals are, and how their life-long bonds with family members pay off by allowing them to teach one another and refine their hunting methods.


While we spent most of our time with this group of transients, we did see another male orca off on his own a little ways off. He was later identified as T14, also known as Pender, a lone bull periodically seen in the San Juan Islands throughout the year. I wonder what his association with this other group of whales was like: what was he doing in their vicinity?

After leaving the whales, we stopped by Bird Rocks a little further to the north where we saw three adult bald eagles perched on the rocks. There was also a single Steller sea lion hauled out as well as a half dozen or more harbor seals. I thought it was a perfect example of how amazing wildlife viewing in the Pacific Northwest can be: orcas, sea lions, seals, and eagles all within about a half-mile of each other.

3 comments:

  1. An exciting beginning to the 2010 season!

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  2. Out and about on the waves again then Monika!
    Reading your post gives me the inspiration and re-newed vigour to get out and find something good :-)

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  3. So you were on the Western Prince. I was on the Deception Pass tour boat and I had a couple photos with the Western Prince in the background that I deleted because the orcas weren't sharp, oh well. Thanks for filling out the details. Here are the pics I took if you want to check them out: http://www.flickr.com/photos/17421030@N03/sets/72157623711919361/

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