For whatever reason, those orcas are the ultimate salmon snobs. Chinook are, by far, their favorite (just like every other living thing).
Ironically, those finicky finsters may be instrumental in eventually forcing the open ocean quotas down in the northern intercept fisheries (AK and BC), which could actually benefit fishing (for all species) round here. We'll see. These days, it seems more likely we'd let the orcas die.8
This bunch is clearly in the minority. Otherwise, we wouldn't have the out-of-control seal population we do in the Sound. Studies in the Sound have found that orcas only seem to eat pinnipeds in the complete absence of something better (much like humans).
Just want to clarify-and will find references, the resident Orca pods key on salmon, and do not move over to seals or sea lions, much-if at all.
The transient whales that come and go, key on seals and sea lions. These are pretty different whales by food choice.
If the transient Orca switched over to seals or sea lions much at all, they'd not be starving, they seem to choose starving.
Here we go:
Orca (Orcinus orca)
The Orca, or killer whale, with its striking black and white coloring, is one of the best known of all the cetaceans. There are two types of Orcas found in our local waters: Resident Orcas (fish-eaters) and Transient Orcas (marine mammal eaters). There are about 78 Orcas in the Southern Resident Orca pods of J, K & L Pod and an even larger number of Transient Orcas. This large number of Orcas is why Victoria is one of the best places in the world to observe Orcas in the wild. Orcas are actually the largest member of the Dolphin family, Delphinidae. They are highly intelligent animals and are the number one predator in the ocean. Resident Orcas travel in tight family groups commonly referred to as ‘pods’, with larger pods comprising over 40 whales (L-pod). Orcas can travel up to 160 kms (100 miles) in a 24-hour period and reach speeds up t0 50 kph (31 mph)!
There is plenty of seal and sea lion predatation going on by transient Orca in Puget Sound and Hood Canal/Strait. They just cannot keep up with the breeding pinnipeds.
Remember the Orca chowdown in Hood Canal a few years back with the big Harbor Seal population? A nice correction!
And more here, on the resident whales and lack of ability to move off of salmon.
"The Southern Resident killer whales are listed as endangered under the Endangered Species Act. Despite efforts to protect them, a major reason why their numbers have failed to recover appears to be a lack of salmon.
It seems unlikely that these whales would begin to eat harbor porpoises, since their ancestors probably ate fish for thousands of years, Giles said. But if they were to alter their diet, she would like to have a record of their behavior leading up to that moment."
Since we don't typically harvest Orca's for food why shouldn't we try to control their harvest of salmon, which we do typically harvest for food? Maybe killer dolphins are predators of the fish we spend millions of money on so we can harvest them for ourselves? Maybe some marine mammals need to be controlled. Maybe we could convince them they'd do better for themselves if they stayed out of Puget Sound or any other sound around. Maybe we could teach them to eat pinnepeds instead of salmon or maybe we could cull the salmon eaters and let the pinneped eaters survive.