Fishing for Landlocked Chinook Salmon on Lake Coeur d'Alene

Outdoor update flash!  Went fishing on Lake Coeur d’Alene yesterday for landlocked Chinook Salmon.  There is an interesting back-story behind this fish population.  I thought I’d share.

Historically, it is believed that Lake Coeur d’Alene would not have had salmon runs in it (but no one knows for sure).  The salmon would have run from the Pacific Ocean into the Columbia River, then up the Spokane River to spawn, but they were blocked from entering Lake Coeur d’Alene by Post Falls, about 6 miles below the lake on the lake’s outlet: the Spokane River.  The construction of Grand Coulee dam on the Columbia River in the 1930s blocked passage to all salmon upstream, and so the salmon runs in the Spokane River near Lake Coeur d’Alene were extirpated. 

Some salmon, however, lived on. 

Life…  finds a… way…

There were sockeye salmon that made the long runs from the lake to the ocean and back prior to the dam being constructed.  Sockeye salmon are different from other salmon, in that they spawn in lakes, and spend a good portion of their juvenile lives in the lakes before they run downstream into rivers and head for the ocean.  Most salmon spawn in rivers, and more or less start their trek to the ocean on day one of their lives, as the river washes them downstream. 

The thing about sockeye is that some of them never leave the lake, even back in the days when they still could head for the ocean.  No one really knows why they adapted to do this, but they’ve been doing it for millennia, and it gave them a unique advantage over the other salmon species when we humans came along and built the dams. 

The sockeye that hang back and never go anadramous are called “kokanee” and the lakes around here, including Coeur d’Alene, are all full of them.  They don’t typically get as big as the ocean-run sockeye did.  The average ocean run sockeye in this system would be in the 3 to 5 pound range.  The average kokanee is less than a pound. 

The thing is that like their ocean-run brethren, the kokanee are delicious.  Anglers highly prize kokanee, not for their size or their fight, but because they are excellent table fare.  But their size is a concern, because, hell, if you’re going to go catch them, why not try to make them bigger and better fighters? 

Some lakes, like Lake Roosevelt (a lake actually created by Grand Coulee dam, and isolated from the ocean-run salmon at the same time as its creation) boast very large kokanee; they approach their size of the ocean run brethren in that lake.  The speculation for this is that there are also landlocked Chinook (also known as King) Salmon in Roosevelt.  The landlocked Chinook in Lake Roosevelt are 100% natural – no one put them there.  Lake Roosevelt is a reservoir created by Grand Coulee Dam, and is part of the Columbia River, meaning that the river that used to run through where the lake is now used to have some of the most epic salmon runs the world had ever seen, prior to the construction of Grand Coulee Dam.  In the Lake Coeur d’Alene and Spokane River system, none of the Chinook survived the damming.  In the Lake Roosevelt system, some did; and those that did adapted to life in a huge freshwater lake, as opposed to a huge saltwater ocean.

Dude, seriously.  I’m telling you that life… finds… a way…

The presence of the land-locked Chinook Salmon in Lake Roosevelt had a curious effect on the land-locked Sockeye Salmon (kokanee) in Lake Roosevelt: they got BIG.  The theory is that the Chinook, being very voracious, predatory fish, fed on the smaller, plankton-feeding kokanee (that’s another interesting thing about the Sockeye – they are the only salmon species that isn’t primarily a predator, and instead eat zooplankton).  The kokanee that survived were typically the ones that had grown large enough to avoid being eaten, meaning the genetic strain in the lake was modified to favor larger fish.  Also, the culling resulted in there being more food for the larger kokanee that were left, meaning that they grew larger. 

Idaho Department of Fish and Game did not miss this observation, and so decided that if it worked in Lake Roosevelt, it would surely work in Lake Coeur d’Alene, which had a population of kokanee in it, also (presumably a remnant from a time before Post Falls blocked the salmon from getting into Lake Coeur d’Alene – or maybe they were introduced.  I’m not sure).  So, back in the 70s, they decided to release Chinook Salmon into Lake Coeur d’Alene to see if they could help make the kokanee fishery better, like they did in Lake Roosevelt. 

When they released them, the IDFG made two assumptions:

1.      That the existence of Chinook Salmon in Lake Coeur d’Alene would only be temporary, since it was assumed that they would be unable to reproduce and create a self-sustaining population. 

2.      That the Chinook population would necessarily result in larger kokanee. 

They were wrong on both counts, at least so far. 

The kokanee population crashed.  There was some speculation as to why this might have been, but many people thought that this was actually part of the process of culling the kokanee and allowing them to grow larger.  No one knew what had happened to the kokanee in Roosevelt after the dam was built – maybe their population crashed, too? 

Also, the Chinook started swimming up the Coeur d’Alene and St. Joe rivers and spawning.  Coeur d’Alene lake became their new ocean, and they became a self-sustaining, viable population. 

I’m not going to say it again…

IDFG panicked.  They started flying helicopter sorties up the rivers to spot Chinook spawning reds and destroy them, to no avail.  Throughout most of the 1980’s, the IDFG was on a mission to try and get the Chinook out off the lake and save the kokanee.  In the 90’s however, they had a realization:

The kokanee were coming back.  They weren’t any bigger, but they were coming back in good enough numbers to say that they had returned, and their populations are still in good enough numbers that IDFG isn’t worried about them anymore. 

They also realized one other thing:

Anglers absolutely loved the Chinook Salmon fishery, and the presence of Chinook in that lake was bringing in lots and lots of money to the local economy. 

So they built a hatchery and started putting Chinook in the lake again.  Everything seems to have found a nice balance, and it appears as though maybe the kokanee are getting bigger, slowly. 

But the Chinook…  oh, man, the Chinook.  They are getting BIG.  There is a reason that they call them King Salmon, and it’s because on a size basis, none of the other salmon species even get close.  Last year during the Chinook derby on the lake, a lady caught a 27.7 pound Chinook Salmon out of Lake Coeur d’Alene.  That is the size of a three year old child.  That is a big fish, ladies and gentlemen. 

And so, whenever the remaining anadramous rivers around here aren’t currently experiencing a run of salmon or steelhead, I augment my fishing habit by heading for Lake Coeur d’Alene and fishing for land-locked Chinook Salmon.  Yesterday, after work, I did just that.  I fished from 5 pm until after dark.  We hooked 4, and boated two.  They weren’t very big, but the big ones are out there, and the intoxicating possibility that I might catch one of them draws me back, day after day, to face the often rough and white-capped waters of this amazing, beautiful lake.