Blue Salmon Spawning - Southern Oregon Gallery
In order to return home salmon often have to jump, thus their name which comes from the Latin salmo, which in turn comes from salire, meaning "to leap". (Wikipedia and other sites)
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The six species of west coast Salmonids (
Oncorhynchus spp) are migratory fish that may travel thousands of miles from their native streams or rivers and across the Pacific Ocean to Alaskan waters and along the Aleutian archipelago. Most travel for at least two years (pinks) and others for four to five years, feeding and growing in the northern Pacific. Historically, Chinook salmon for example (aka King, Spring, or Tyee [when greater than 30 lbs.]), were found to grow up to a hundred pounds and more from feeding in the icy waters of the north pacific ocean, rich in nutritious food fish and plankton. When they reach sexual maturity their “return home” genes are triggered hormonally to tell them that it is time to begin their final journey to their natal stream to spawn the next generation that will begin the venerable cycle again.
Please step over the salmon egg sac below and continue with the story:
Particular cohorts of each species seem to get these messages at about the same time as they travel together and eventually converge en masse on their ancestral streams. Males and females alike reverse their migratory paths to find the fresh waters from which they emerged several years previously. Their journey back to fresh water is guided by geomagnetic reckoning, akin to that used by other migrant animals such as elephant seals, tuna, sea turtles, and eels, among others.
"For salmon to find their way back home, they remember the magnetic field that exists where they first enter the sea as juveniles, and once they reach maturity, they seek that same coastal location, with the same magnetic field.”
Once they navigate to familiar freshwater they head upstream, in some cases hundreds of miles up forking streams and rivers, seeking a shallow stream bed in which to build their redds. Guidance for the freshwater portion of the journey is based on olfactory memories acquired during early development in their natal waters. They are able to discriminate olfactory cues in the waters of various legs that were imprinted in their brains as they developed before their migration and that later guide them up stream. These paths can be as simple as an estuary with a single stream leading out of it. Alternatively, they might return to large rivers systems such as the Columbia with its numerous tributaries, and lakes followed by multiple branching streams, each to be decoded before finding “home.”
Those who escape predators (larger fish, fishing nets and hooks, bears, raptors) and find home, dig their redds in the stream bed, often with males’ assistance. Females lay their eggs and an accompanying male is present to fertilize them. They will dig as many redds as it takes to deposit all their eggs. Thus starts the next cycle of salmon. After they spawn the salmon die, having exhausted all their physical resources. They stop eating when they encounter fresh water and they batter their bodies on their often arduous journey home, jumping falls, and nowadays for many, jumping fish ladders. Their destiny is to deposit and fertilize their eggs and then return their bodies to nature as nutrients. Those spawners that do not become food for bears and raptors, decompose into the stream bed and support stream and riparian vegetation. The remains of the predators' meals are dropped in the woods where they too become important nutrients for the flora.
Image credit: nagillum via flickr, CC
Eons before human ancestors came down from the trees of Africa, these fish were coming home. The salmon family (Salmonidae) cycle of life has been around for many millions of years. Speciation into the current 6 Pacific salmonid species (Oncorhynchus) including the Steelhead Trout) and their separation from Atlantic salmon (Salmo) occurred by the early Miocene, between 15 and 20 million years ago. The fact that they have adapted to many changing environments over this enormous time span, allows one to hope they can adapt to the current and coming climate changes. The question will be: how much time do they need to make their adaptations to a warmer world? They are already changing their migratory routes. And on their return, will they find a welcoming habitat in which to spawn?
Salmon Culture Among The Pacific Northwest Indigenous peoples.
First Salmon by Roxane Beauclair Salonen
On a more human timeframe, salmon have provided sustenance for North Americans from the time they arrived and likely during their journeys from Asia. Salmon have been a major sustaining part of the lives of First Nations people from Alaska, down through British Columbia, Washington, Oregon, and Northern California. Salmon have been a part of a sacred cycle of life that has sustained the indigenous peoples of North America for greater than 12,000 years. The same is likely true for some of the aboriginals of eastern pacific shores as well. (I just don’t have their salmon history).
The tribes that lived along any waterway that connected to the Pacific Ocean all had ceremonies honoring the return of salmon each spring when the first runs began. The salmon was and remains sacred to them.
Historically, first-salmon ceremonies differed from tribe to tribe, but all had some things in common. The salmon chief of the tribe would select a fisher to catch the first salmon. This was an honor, and before entering the river the fisher would undergo a blessing or a purification. Once a fish was caught, it would be brought to shore and carefully prepared, cooked and distributed to the people in a manner unique to the location and tribe. The head of the fish would be kept pointed upriver to show the salmon’s spirit the way home. The bones would be carefully cleaned and returned to the river, where it was believed the salmon would reconstitute itself and continue its journey. Throughout, there was an underlying theme of respect for the salmon as a gift, and the hope that by properly respecting the fish the salmon king would continue his benevolence through the coming months of salmon returns and again the following year.
Lummi Nation Elder celebrates first Salmon Ceremony. Attribution: Flickr Commons
First Salmon Returned to water. Attribution: Flickr Commons
The importance of this salmon cycle to Native populations and their fear of losing the heritage is expressed in a recent song by Dana Lyons, inspired by the first nations and indigenous populations of Alaska. Dana Lyons is a local musician, an avid environmentalist, and a promoter of native rights and culture. He is a troubadour for saving the salmon, their waters, and habitat. This piece relates to all salmon cultures but its immediate focus was to drum up opposition to the Pebble mine project located at the head waters of two rivers that feed into Bristol Bay, the home to the world's largest salmon run. Several of the original investors in the Pebble Mine project have recently backed out, so maybe there is hope.
Salmon return to Whatcom Creek, 2014
The fruits of the Whatcom Creek Hatchery’s labor continue to come back with a new cohort of chum and other salmon arriving each fall. Although the timing of the return of Whatcom Creek salmon is too late to participate in any First Salmon Ceremony, other sorts of rituals are enacted at the Creek’s estuary each fall. Many thousands of salmonids return, most of which are Chum, with a few Coho and pinks, along with the occasional Steelhead Trout. These successful sojourners will follow one of three pathways as they meet their destinies after reaching their fresh water estuary. No matter which pathway they take, their final destiny is their demise.
Some survive the gauntlet of fishermen beating the water with their lines and brightly colored lures. This stalwart group then must climb the first of several falls in order to return to their upstream spawning grounds where they will pass on their genes in the age old fashion before succumbing to nature’s destiny.
Lower falls, Whatcom Creek
A second group confronts fishers although fishing at this stage of the return is a bit dicey.
Fishers line up at Whatcom Creek to snag a salmon
Recall that the fish stop feeding when they hit fresh water. They have no interest in either live bait or artificial lures. So, how can one entice a non-hungry fish to bite a hook? Most fish instinctively snap at brightly colored objects. Florescent red, yellow, and green lures are used in an attempt to grab their attention. The fish will often lunge and snap at these brightly colored hooked lures. Sometimes they actually get the hook in their mouth and get caught but often they will charge the lure, twist, flip, and get snagged by the hook in various parts of their bodies.
In the first case where they are hooked in the mouth, they are legally caught and if landed, can be kept toward a limit of two per day.
A legally caught spawner
In the second case, since it is illegal to snag a fish, or more practically, to keep a snagged fish, they must be released.
A snagged fish, can't be kept
Little Harbor Seal on the fish Ladder - tagged, or Collateral damage?
The third group consists largely, but not exclusively of hatchery spawned fish that developed into smolts (juvenile salmon) in these waters. They recognize the chemical characteristics of this water and find the fish ladder. The ladder then takes them up to the hatchery holding pond where they await their destiny of being thumped on the head, their eggs taken, incubated, and fertilized.
Once in the holding pond their upstream drive is still strong even as they jump against the gates.
Salmon keep jumping in the pond
The video below shows the salmon coming up the fish ladder into the holding pond. Note how their snouts, tails, and fins are rubbed raw. Also see how they seem to rub their underbodies and tails across the fish ladder as if they were making a redd and spawning. This rubbing activity stimulates the release of eggs. You can see eggs coming out of one of them in the video as she moves across the edge of the fish ladder at 14" and again at 40” into the video.
The Whatcom Creek facility harvested about 3 million eggs this fall. Ultimately once hatched and released many of these, like their parents will return to the estuary until development into smolts. Smolting allows them to live in salt water and prepares them to set off on their own epic journey across the Pacific. And so it goes around again.
Typically the salmon are harvested just before Thanksgiving. After their eggs are stripped, those carcasses that are edible are processed and donated to the local food bank. At this final stage of their cycle, many are thoroughly spent, their skin and flesh is soft and scarred, and much of their bodily resources depleted. The less desirable are sent to become fertilizer as will those who die while in the holding pond.
Whether they return up stream where their bodies are decomposed by natural processes or are harvested by hatchery officials, they complete their life cycle of life by returning the elements from which they came, back to mother nature.
As Dana Lyon says: "Salmon Come home, again and again..."
Let's work to keep this millions year old tradition alive.
Previous Buckets on PNW salmon preservation:
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