Oncorhynchus nerka
Dr. Jekyll & Mr. Hyde?
A crystal-clear creek, full of red fish, emerald flora all around - WOW! Photos came first, questions followed later. I knew that they were called "landlocked salmon" and that they were good to eat. I also knew that they were silver for the most of their lives and that they turned red only before they started to spawn which was about in August.
That was it.
It wasn't until Richard said: "Kokanee are Sockeye, you know? Let kokanee go downstream and into the ocean and they'll come back as Sockeye Salmon."
Now, how could that be possible? One is either a kokanee or a sockeye, no? I stared at the photos of the small, slim fish with more and more questions mushrooming in my mind.
When in doubt, go to Wikipedia, then try other sites.
According to Wikipedia the name Sockeye, is the anglicized suk-kegh from one of the coastal Salishian languages (Halkomelem tribe), meaning "red fish". Kokanee came from kukeni or kekeni of the interior tribes, possibly the Sinixt of the Kootenays, meaning .... "red fish". One lives in the ocean, the other in freshwater lakes. One grows large the other is half of the other's size - if lucky. But, according to what I just learned, they are one and the same.
It became really tempting to think of the two as Dr Jekyll and Mr. Hyde, but then I thought that such a comparison would be totally unfair to the fish.
I do not have a photograph of a Sockeye Salmon (Oncorhynchus nerka) yet! The above guys are kokanee (Oncorhynchus nerka). See? Their Latin names are the same.
It is well documented that each
summer, the adult sockeye salmon travel back from Pacific and up through the rivers
and streams to the place of their birth (in most cases) to spawn.
That is the time when many of us head outdoors to witness the migration. We do not think about the immense physiological changes that must take place so that the streamlined, ocean dwelling fish loose their silver shine and become aggressive, red-and-olive hunchbacks of the freshwater streams.
All we see is a mass of red bodies, males redder and darker with menacingly deformed jaws full of sharp, brand new teeth. Once spawning, sockeye do not eat at all, the energy they need is stored in their fat - especially in the hump on their back; their teeth are only there to help them establish the most favorable position within the spawning crowd.
It was the curved jaw that gave the taxonomists an idea to call the salmon: Oncho-rhynchus – the hooked-nose one.
That is the time when many of us head outdoors to witness the migration. We do not think about the immense physiological changes that must take place so that the streamlined, ocean dwelling fish loose their silver shine and become aggressive, red-and-olive hunchbacks of the freshwater streams.
All we see is a mass of red bodies, males redder and darker with menacingly deformed jaws full of sharp, brand new teeth. Once spawning, sockeye do not eat at all, the energy they need is stored in their fat - especially in the hump on their back; their teeth are only there to help them establish the most favorable position within the spawning crowd.
It was the curved jaw that gave the taxonomists an idea to call the salmon: Oncho-rhynchus – the hooked-nose one.
In the ocean, sockeye salmon feed upon marine zooplankton that they strain through a special apparatus incorporated within their gills. It is called gill rakers and it acts like a sieve - water that came in through the mouth is expelled out and into the ocean, through the gills. Oxygen diffuses into the gills and myriads of zooplankton are trapped in the gill rakers and swallowed soon after in one gulp. Sockeye may add some small fish or another soft-bodied creature to their diet but the main bulk of what they eat consists of those tiny creatures that the oceans are (still) teaming with. It is a diet rich in nutrients and carotenoids - red and orange pigments, whose job is to protect the tiny creatures from UV light.
That's why the sockeye flesh turns red.
Sockeye spend several years in the Pacific before heading back to the place of their birth - back from the salty ocean into freshwater rivers and lakes. They reproduce and they die in the places of their conception; a brand new generation left in their wake.
Feeding on freshwater plankton and invertebrates the new salmon stay in freshwater for a couple more years before the set on a journey back to the vast spaces of the ocean.
But what happens when something blocks the waterways so badle that the fish cannot get through?
What will happen to the young sockeye then?
Here comes the part that makes me admire the sockeye the most.
They will “simply” stay put and keep on living in the lake
of their youth, feed by flushing lake water through their gill rakers,
catch a soft-bodied insect here and there and try to make the best out of life. Their colours will remain the same, silver or red, only their sizes and life spans will differ because there is a huge difference in the amounts of food available to those living in the wide ocean as opposed to those eking a living in a cool but quite sterile mountain lake. Sockeye will become Kokanee.
When the time comes and their hormones kick in, the silver "landlocked" kokanee fish will stop feeding, turn crimson red, their heads will re-colour and re-shape and they will undergo the ancient ritual of migrating to the edges of their lake or to adjacent streams. There they will spawn and die without ever experiencing the ocean life.
I
found a neat table that helped me answer a few questions: Here is an
excerpt.
COMMON COMMON MAX MAX LIFESPAN
LENGTH WEIGHT LENGTH WEIGHT
_____________________________________________________________________________________________
SOCKEYE 60 cm 85cm 7.5 kg 8 years
KOKANEE 20-25 cm 0.15 kg 60 cm 4.5 kg 4 years
_____________________________________________________________________________________________
So, from here on, I will only think of the slim, landlocked KOKANEE, the red fish of
the West Kootenays (and most of North America).
The Kootenays with their dammed rivers and large lakes are
“kokanee country”. Many places around here are called kokanee this and kokanee
that …. Kokanee Park, Kokanee Glacier, Kokanee Beer … Red Fish Creek and Red
Fish Elementary amongst the others.
I wonder if anyone in the designer world will ever come up with kokanee red.
Someone take a notice please – it is an amazingly deep and rich colour. After all – we
do have wasabi green!
West Kootenays could be defined by two major river
systems: Columbia River with Arrow Lakes and Monashee Mountains towards the West, Selkirk Mountains in the middle and Kootenay River with Kootenay Lake between the Selkirks and Purcell Mountains in the East. Both rivers have been heavily dammed and kokanee made their permanent homes in the two lakes.
Arrow and Kootenay lakes are deep, rocky bodies of cold water with insufficient plant life that could in turn support zooplankton that the kokanee feed on.
Which means that kokanee food supply can become problematic at times, especially when there is a population explosion of the species. It is all a bit more complicated than this (thanks to the dams on both ends of the lakes and poor flow of nutrients within the systems but lets not be too technical here). Little zooplankton = less kokanee = less food for fish that prey on kokanee (Gerard Trout, Rainbow Trout) .... the entire system is broken. Just another example why we should stop believing that to exploit and mess up Nature is our God given right.
Kootenay Lake, one of the largest lakes in British Columbia with Selkirk mountains on the right.
Arrow and Kootenay lakes are deep, rocky bodies of cold water with insufficient plant life that could in turn support zooplankton that the kokanee feed on.
Which means that kokanee food supply can become problematic at times, especially when there is a population explosion of the species. It is all a bit more complicated than this (thanks to the dams on both ends of the lakes and poor flow of nutrients within the systems but lets not be too technical here). Little zooplankton = less kokanee = less food for fish that prey on kokanee (Gerard Trout, Rainbow Trout) .... the entire system is broken. Just another example why we should stop believing that to exploit and mess up Nature is our God given right.
Kootenay Lake, one of the largest lakes in British Columbia with Selkirk mountains on the right.
Arrow Lake by Burton near Nakusp. Monashee Mountains in the background.
It was here, at Arrow Lake, just after sunset on August 28th, when I noticed significant splashing by the edge of the lake. There were fish; chasing each other, leaping out of water and acting crazy to say the least.
At first I thought that they were kokanee (correct) practicing for their spawn in a nearby creek (wrong).
Only later did I learn that there are two kinds of spawning kokanee: some spawn by the edge of a lake while others enter the adjacent streams.
I was lucky enough to come upon a spawn in the lake.
To record the lake spawn was difficult because the water in the pool was deep and all I could see disturbances of otherwise calm surface followed by a wild jump here and a there. I had no idea where the fish would emerge so I aimed at a general area of action, focused, set the camera on manual, and holding the cable release, waited (and waited and waited) for the fish in “my” area to jump. Needles to say that they were jumping everywhere else but! Since the sun was setting down somewhere behind the mountain I did not have much time left . Finally one kokanee took pity on me! It shot out of the water, and (within a second or two), splashed back in.
At first I thought that they were kokanee (correct) practicing for their spawn in a nearby creek (wrong).
Only later did I learn that there are two kinds of spawning kokanee: some spawn by the edge of a lake while others enter the adjacent streams.
I was lucky enough to come upon a spawn in the lake.
To record the lake spawn was difficult because the water in the pool was deep and all I could see disturbances of otherwise calm surface followed by a wild jump here and a there. I had no idea where the fish would emerge so I aimed at a general area of action, focused, set the camera on manual, and holding the cable release, waited (and waited and waited) for the fish in “my” area to jump. Needles to say that they were jumping everywhere else but! Since the sun was setting down somewhere behind the mountain I did not have much time left . Finally one kokanee took pity on me! It shot out of the water, and (within a second or two), splashed back in.
The shutter went crazy and the image of that brave little kokanee will stay etched in my memory forever.
I repeated the same process the following evening – the
lake was quiet, its surface like the proverbial glass. At sunset the water started to boil! The fish went berserk.
Greedy to get a picture I worked hard, not noticing that a couple of local
residents came over to pay me a visit. Strangely, they did not seem too friendly at first.
“So ….
what are you taking pictures of?’, they asked grudgingly.
I realized that my long lens seemed to be aiming at their homes
nestled in the green privacy of the woods by the shore.
“Feesh.” I peeped.
“Fish?”
At that moment a kokanee jumped right in my field of view but I
was too distracted to press the shutter. That got me going!
“Yes! Fish! They are getting ready to spawn – right there!”
(And I missed the shot! Because of you!)
They sensed my disappointment, wished me good evening and
left. Until this day I think that they did not believe me. Maybe they thought that I was
trying to put their house on Google Earth. And I wonder if they knew that some kokanee can spawn right there, in the lake.
To observe "the creekers" you need to find a nice, clean creek with just about the right temperature and the right flow of water (too strong will flush the eggs down the stream and too still will not give them enough oxygen). It should be lined by nice gravel (not too big because it would squish the eggs and not too small because the eggs could not be hidden).
One such creek on Arrow Lake near Burton is McDonald Creek, a well known site where one can observe the fish.
The photos below were taken at a different site.
They are Kokanee Creek and the Kokanee Creek spawning channel on Kootenay Lake by Nelson.
Everything in Nature is connected and many creatures depend on spawning salmon. Animal, plant and other worlds all benefit from the spawning event and many drift in as soon as the fish come near shores. They will feed and distribute the bodies of the dead and dying fish, for kokanee, like all salmon, die after the spawn. Someone at Kokanee creek channel asked me a question:
"Are you knowledgeable?"
"It depends. Knowledgeable about what?"
"Do kokanee spawn more than once? Someone said they do ..."
"Hmm, I don't think so but I am never sure of anything ... "
So I asked Richard.
"Kokanee are salmon. They can live up to 4 years but once they spawn they die. Trout are different, they can spawn two or three times."
Thanks Rich.
The Others
They come for the feast. They fly, swim, walk or crawl. They will take the fish and carry it away. They will eat some and leave some for the trees, They will take the rotting bodies apart until the nutrients get back to the system. Nature wastes nothing.
While the world around them is observing or searching for their eggs and flesh, kokanee procreate.
Females are on a lookout for some suitable part of the creek where they can release their eggs (roe). When they find the place they wiggle their bodies sideways and flap their tails to dig a shallow depression; it is a "nest" called the redd. Males keep on fighting for a position nearby. The fights can be quite nasty - we observed the fish to bite their opponents with their large teeth, the opponent shaking its body violently to get free of the hold. Ouch!
Females are on a lookout for some suitable part of the creek where they can release their eggs (roe). When they find the place they wiggle their bodies sideways and flap their tails to dig a shallow depression; it is a "nest" called the redd. Males keep on fighting for a position nearby. The fights can be quite nasty - we observed the fish to bite their opponents with their large teeth, the opponent shaking its body violently to get free of the hold. Ouch!
When the work is done the female chooses her partner, releases part of her eggs, and at the same time the male fertilizes them with his sperm (milt). It all takes a couple of seconds followed by a few tail flaps to cover the eggs and the female is off . She will build build another redd in another location and choose a different partner. There will be three or maybe four redds built and fertilized before all of her the eggs are released.
Within a week of making the last redd the spawned fish, male and female alike, will be dead.
Within a week of making the last redd the spawned fish, male and female alike, will be dead.
One cycle of life will have ended.
Another cycle will begin.
Another cycle will begin.
The eggs will "hatch" and after several stages the little kokanee will swim - fast and under the cover of darkness - into their lake. There they will feed and grow and after three, four years they will return to the place of their conception - be it the edge of a lake or a mountain stream.
Would they change into a sockeye given a chance to migrate into the ocean? Some say yes.
I am at awe at the concept - but I am not knowledgeable enough to confirm. Although, I know now that they, the kokanee, can spawn only, only, once.
I am at awe at the concept - but I am not knowledgeable enough to confirm. Although, I know now that they, the kokanee, can spawn only, only, once.
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