1 Fish, 2 Fish, Small Fish, Big Fish

Are you or anyone you know a picky eater? Many of us will refuse to touch certain foods or will only eat something if it is prepared a certain way. However annoying a picky eater may be, they are not alone in the mammalian world of choosy eaters.

Photo credit: American Rivers

Another iconic Puget Sound mammal, the Southern Resident orca, is also indeed a picky eater.  This orca’s favorite dish is, hands down, the Chinook salmon. The health and abundance of southern resident orca populations rely heavily on the health and abundance of Chinook salmon populations. It is no surprise then that as Chinook populations decline we are also seeing our southern resident orca whale populations struggling to survive. To make matters worse, not only do these orcas prefer Chinook salmon, but they also prefer large mature Chinook as they deliver more nutrients for the hunting effort.

In contrast, orca populations located north of the Salish Sea in British Columbia and Alaska are thriving. There are reportedly more than 300 northern residents and close to 2,300 Alaska orcas, while our southern residents struggle at 73. So why are orca populations located north of the Salish Sea faring so much better? The reason could be cleaner quieter water, or it could be that northern orca populations are getting the first pick at the preferred large Chinook salmon, leaving the southern resident population with smaller fish.

Chinook salmon that originate in streams and rivers in the Puget Sound area migrate thousands of miles north to the Gulf of Alaska to fatten up in the ocean before returning home to spawn. On their journey home these salmon have to migrate through the feeding grounds of several different killer whale populations that have a keen affinity for big Chinook. It is possible that these thriving northern orca populations are essentially stealing a meal from the southern resident orca population.

Although these separate orca populations avoid each other in the ocean, they are in fact competing with each other their whole lives. Our resident orcas need all the help they can get and we must all do our part! Puget Sound Starts Here! It starts at your home, business, and school. Let’s remember that small actions really do add up to have big effects.

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