Thursday, July 11, 2013

Samantha, the Sacrificial Salmon

Years ago, when the girls were little, we got a couple of 25-cent goldfish for Naw-Ruz, the Baha'i new year. The girls named them Blackfin and Princess. Blackfin lasted all of two weeks. Princess defied the odds and thrived for two years, despite her owners sometimes neglecting to clean her fish bowl and occasionally forgetting to feed her.

That pretty much sums up my life experience with fish.

Quite frankly, I've always thought of fish as not all that interesting. I mean, I love to marvel the diversity of marine life at the aquarium, but other than that, and an occasional meal, I've generally never given fish much credit for . . . well, anything at all.

So learning about the life of salmon at the Chittenden Locks in Ballard this week was really eye-opening. I'm sure I learned about the salmon cycle before (like the last time we came to the locks a few years ago), but this time we had a passionate gentleman explain the whole thing to us, and it gave me a whole new appreciation for these amazing creatures.

Truly, an individual salmon's story is a fascinating tale of miraculous transformation, perilous adventure, enormous effort, and ultimate sacrifice.

Who knew?

To illustrate a bit of what we learned at the locks, I'm going to tell you about a salmon that may or may not have really lived. But it's a true story, nonetheless.

We'll call her Sam, for short.

Sam's story starts in the fresh waters of the Sammamish river, where she hatches under a bed of gravel, along with thousands of her siblings. The little salmon babies immediately head downstream, feeding on the nutrient-rich insect larvae that line the riverbed. They're headed for the Pacific Ocean.

After they've taken their time swimming down the length of the river, they arrive at Lake Washington, smack dab in the middle of Seattle. Lake Washington leads straight into Puget Sound, but the two bodies of water are separated by the Chittenden Locks. The main purposes of the locks are 1) to keep the freshwater and saltwater separate, so as not to mess with each ecosystem, 2) to keep the water level of Lake Washington stable at 20 to 22 feet above sea level, and 3) to move boats from one water level to the other.

This is where boats enter the lock.

This is the gate opening to let a boat out into the lake after the lock has been filled. Imagine the gate being closed and the water on the other side of it down about 20 feet. That's what the lock is like before it's filled. Trust me, it's cool.

So, it's basically a dam, and the locks themselves are like holding tanks/elevators for ships going through the channel. The boat enters the lock, the gates close, and water is either pumped in or out of the lock (depending on whether the boat is going into Lake Washington, which is higher, or out to Puget Sound, which is lower) to the appropriate level. Then the gates open on the other side, and the boat moves on. It's pretty fun to watch the ships go up and down. Quite a feat of engineering.

But back to Samantha's story.

Sam arrives at the locks as a smolt (a little teenage salmon, basically). Miraculously, during her journey to the locks, her body has undergone an amazing transition called smoltification, in which she changes from a freshwater creature to a saltwater one. How bizarre and cool is that? (And how fun of a word is smoltification?)

Since the locks are blocking her way to the sound, Sam appears to be stuck in the lake at first. But no worries, the U.S. Army Corps of Engineers who built the locks took great care to make sure the salmon cycle wouldn't be disturbed. For the smolts heading to the sound, they have these super fun slides to ride.




Sam gets to the spillway and the slide shoots her and her smolt friends on through, tail first. No harm done. Whoosh! Welcome to Puget Sound, Sam!

Sam will swim through the sound and spend the next several years hanging out in the Pacific, growing larger and stronger and gathering up all the rich nutrients from the ocean's saltwater. She'll have a few narrow escapes with fishing nets and killer whales, but she'll survive.

Then suddenly, one day, she'll feel an overwhelming urge to return to the Sammamish river where she was hatched. This longing for home will lead her right back to the locks, where she will encounter another brilliant feat of engineering: The Fish Ladder.


Now let me tell you, Sam is an excellent jumper. She can fling herself a good ten feet out of the water, at least. But the 22 feet she'd need to jump to clear the dam would be pretty impossible. And the chances of her getting into a lock at just the right time is pretty small.

So the fish ladder gives her an easier (though certainly not easy) way to ascend to the waters of Lake Washington. Each of the 21 steps of the ladder goes up about a foot, and Sam can climb up at her own pace. Sometimes she'll wriggle her way up the small spill over the step, and sometimes she's jump right up out of the water from one step to another.

JUMP, SAM! [Just FYI, it is REALLY hard to get a photo of a salmon jumping out of the water. Quick little buggers.]
She swims and jumps upstream the whole way up the ladder. But that's okay. She'll have an upstream swim for the remaining months of her life. Not only that, she'll do it without food. She stopped eating shortly before arriving at the locks, and won't eat again. Ever. She has a singular goal - to get back to the riverbed to spawn her eggs. Nothing else matters.

So she climbs the ladder, making the difficult (and presumably somewhat uncomfortable) transition from saltwater to freshwater again. The lock engineers gave Sam and her friends an extra long step in the fish ladder just before they reach the lake, to give them time to make the transition more slowly. Wasn't that thoughtful?

Luckily, Sam makes it up the ladder and through Lake Washington without incident, and over the course of a few months, returns to her spawning place in the Sammamish River. She's one of the lucky ones. Only a small handful of her thousands of siblings have survived to this point.

Once she finds the perfect spot to spawn, she flips herself onto her side and slaps the gravel with her tail fin, creating a nest of sorts. Males fight, sometimes to the death, for the right to swim up beside her, hoping to be the one to fertilize her eggs with his sperm as they fall into the next. After her first batch of eggs is fertilized and laid, she goes upstream a bit and makes another nest. Then another. Then another. Why upstream? Because the stirring up of the riverbed helps to cover the previous nest, protecting the eggs in several inches of gravel. Brilliant! Sam's no dummy.

She's also no slacker mom. She has survived the past few months without food by cannibalizing herself, using her own body oils and nutrients to keep her alive long enough to spawn. Once she's finished spawning, her thousands of eggs safely tucked away in the gravel, she perishes. Her body, barely held together until now, breaks apart, and the rich nutrients she gathered in the Pacific - particularly nitrogen and phosphorous, which she alone sacrificially offers to the river's ecosystem - will feed the insect larvae that live there. And those larvae will ultimately feed her baby salmon when they hatch.

What a perfect cycle! I hope you find it as fascinating as I did. Maybe you needed to have that enthusiastic guy there to really drive the coolness factor home. I think it's just fantastic.

Interestingly, scientists are really just figuring out how much of a vital role salmon play in the health of river ecosystems. They bring nutrients from the ocean that the river doesn't get anywhere else. They feed their babies with their dead bodies, yes, but they ultimately provide food and nutrients for countless other creatures as well.

Just more evidence that we truly are all connected. It's a good thing to remember.

"It is obvious that all created things are connected one to another by a linkage complete and perfect . . . " - 'Abdu'l-Baha 

Sorry, fishies, that I never gave you any credit. I promise I'll never underestimate you again.


*Disclaimer: I tried to relay the information about the salmon cycle as accurately as I remembered it, and I looked up things I wasn't sure about, but it's entirely possible that I was sure about some things that I shouldn't have been sure about. :) For some official information about the locks and the salmon cycle, go here:

The Hiram M. Chittenden Locks
The Salmon Cycle

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