The life of a coho salmon isn't easy. I should know. I am one.
Things were tough right from the start. My first memory is just bouncing around the river bottom as a small, pink, sphere. It was me and all my brothers and sisters.
"Cohos tend to have as many eggs as the size they are, typically 3,000 to 3,400 eggs, compared to pinks, which are smaller and will only have around 1,000 to 1,500 eggs," said Patti Berkhahn, a fisheries biologist with the Alaska Department of Fish and Game.
There were a lot of us in the beginning, but our numbers quickly began to dwindle, even at that early age. Some of my siblings met their end after being dug-up from the gravel by other spawning adults. Others were never fertilized because our egg bunch was too dense.
Predation was also a big factor in the mortality of my brothers and sisters, and I witnessed many of them gobbled up by rainbow trout and Dolly Varden, not to forget all the waterfowl that also filled their bellies.
"Eggs can also die as a result of floods in fall, by being crushed by ATVs crossing streams, silt from construction can cover and suffocate them, and they can die from changes in water chemistry. Also, live eggs can be killed by fungus from other dead eggs," Berkhahn said.
Still, my siblings that didn't make it were lucky to have at least had a chance. It's widely known that when parent fish can't reach their preferred spawning areas, often due to hanging culverts or other obstacles, they will lay their eggs in unsuitable areas where there is no hope they could develop properly.
The alevin stage was not easy for us, always lugging around that yolk sac beneath our bellies. It kept us fed, but swimming around with it sure was tiring. Again, I saw many of my siblings succumb to the appetites of trout, char and even a few whitefish.
"The alevin stage is naturally going to be around Christmas time, so they can also be crushed by ice flows, or frozen by dams that lower water levels. They can also be scoured out of the gravel and carried away by high water during a late-winter warm spell," Berkhahn said.
Following the alevin stage, my fishy kin and I emerged as fry, and while we thought things were bad before, once we left the gravel of the river bed, we again found out the hard way how vulnerable we were to predators.
"Mergansers, grebes and other ducks, they'll have a field day on them. Same with the seagulls," Berkhahn said.
A few of my brothers and sister also died when silt from road erosion run-off irritated and damaged their gills. Others starved to death as silt caused our food supply to vanish. And drought locked several unfortunate fish into pools where they became isolated, and eventually died when the water in them dried up as well.
As a smolt, poor water quality in the estuary caused by nearby industrial development forced many of us out to sea early. I survived, but many who couldn't make the physical change to the salty water were not so lucky.
"Out to sea and as an adult, anything can happen. They call fall victim to predation from bigger fish, salmon sharks, killer whales and other predators," Berkhahn said.
After two years developing in the river, followed by my one year out to sea, I grew strong. However, I started to develop a yearning to return to my home stream, and even though I was much larger now, getting back was no less dangerous.
"Commercial fishermen, sport fishermen, subsistence -- we're all eating them, and you can throw bears into that too as salmon come back to spawn," Berkhahn said.
I made it past all the nets and lures though, and found a suitable spot to spawn. Back in the freshwater my body isn't quite what is sued to be, and I fear I may not be long for this world, but when I die I will take solace in knowing I was one of the few who made it all the way.
"It's a small percentage of coho that live long enough to grow up and return and spawn. It's less than 1 percent. There's just a lot of ways for them to go," Berkhahn said.
Joseph Robertia can be reached at email@example.com.
© 2017. All Rights Reserved. | Contact Us