Silver, Red, and Pink Salmon Spawning
Every time I drive through Seward people are peering into the bushes – cameras to their eye. There is absolutely no scenic beauty to the spot. It is just a slough, maybe a drainage ditch flowing out of a marsh on the other side of town. Regardless of the time I pass by – early morning, late afternoon, even after the sun has set; there is a crowd lingering. Why is a crowd always gathered there?
A few days ago I pulled my bicycle from its lofty perch atop my car and set off for Tonsina Point. The point is the half way mark for the trail to Caines Head, where an abandoned fort from World War II stood. Resurrection Bay, Caines Head, and Seward were all very important during World War II. The Port of Seward is the furthest north deep-water American port which remains ice free year around. It was feared that the Japanese who had already captured an island in the Aleutian chain and held the natives captive would advance towards the Alaskan mainland through Seward, across Canada and into the lower 48 states.
Taking a Resurrection Bay tour the military significance of the Bay is evident. Along the steep walled cliffs are bunkers, once the home of brilliant spot lights positioned to illuminate the bay should an enemy be invading. The headlands and islands at the bay’s mouth are leveled off at their highest points, once the home to batteries of six-inch guns. Remnants of an old pier at North Beach remain. North Beach was the supply point for Fort McGilvray and South Beach.
My curious nature wanted me to explore all the way to North Beach, but the final two miles of trail is along the base of a cliffs edge and only passable during low tides. The tides were not in my favour this week. I settled for the shorter bicycle ride to Tonsina Point.
The trail followed an old roadbed but heavy rains in late July had converted it to a rocky streambed – sections of which I walked. The last quarter mile a trail drops off the track to the Bay’s edge. A series of boardwalks cross several seeps before the trail reaches the grassland at the mouth of Tonsina Creek. Stepping onto the bridge I instantly became aware of movement in the water. Fins were breaking the waters surface. Sleek forms, some silver, others red, darted beneath the surface. The salmon were spawning. The trail beyond the creek meandered through a spruce forest, branches heavily encrusted with moss and liverworts giving the trail an almost haunted appeal. The heavy rains had washed the next bridge away. All that remained in the river’s channel was a twisted metal piling. In its place, a springy trunk provided a precarious path over the water to the Tonsina Point Campsite – tent pads, fire grills, a lone outhouse, and cooking shelter are available.
Along the shore are the ghostly, white trunks of a forest – the forest that existed before Good Friday 1964. On Friday the ground shook – rocked violently by the most powerful earthquake known. The ground settled five feet that morning leaving a forest needing fresh water to close to the oceans saline water to survive. Further up the bay, as the ground sank, water rushed out, then returned a few minutes later as a wave forty feet high which washed over the town of Seward as far as 9/10ths of a mile inland. The industrial and city areas along the shore were washed away, cleansed. Today it is maintained by the city as an RV park and campground . . . .
As I came back in to town that evening after my ride, people were still standing on the edge of the slough, camera to their eye. I had my answer. The salmon were spawning.
This afternoon I stopped at the Trail Creek Fish Hatchery. It seemed abnormally quite as I stepped through the stuck door. A lone person was pulling his rubber boot on. His rubber slicker was tossed over the desk. A black lab wagged its tail. Strangely – a large box in the office housed an infrared heat lamp.
“I’m just going out back, you want to come,” was the greeting I received.
“The lanes are mostly empty,” he said as we walked the corridor.
“We release most of our fry in the spring, but we have a few here we keep as yearlings,” as he swung open a door into the backyard where multiple lanes protected by netting greeted my eyes. “Yearlings have better survival then fry when we release them.”
“We’re pretty busy this morning” – it was 1:42pm. “We just brought in a batch of eggs. Come, I’ll show you.”
I was led to another room. “If you’ll just stay here I’ll tell you about it.” A technician was holding a zip lock baggy with a mass of red in it. Tray after tray – ten extra-large, Coca-Cola cups per tray were stacked atop each other.
“Each bags holds about 3,000 eggs. We collected them this morning. We dump them into a Coca-Cola cup. Then, Over here,” he pointed to pile of Solo cups I was more accustomed to finding salsa or sour cream in, “is the sperm.”
“We’re just getting setup. If you wander around for a few minutes you can come back and watch, but I’d prefer you didn’t come in the room.”
A single hallway housed their interpretive exhibit. A small aquarium held some fry. Behind a security glass viewing window were a couple other lanes – also dry. Summer is the slow time. Most of the fish – the fry – are released in the spring. A few lanes hold the fry where they are being raised to yearlings.
In late summer they start the breeding cycle again.
This morning they had been up at Bear Lake collecting fish. A quick thunk on the head and the fish is killed. The ventral surface is sliced open and the eggs are dropped into a zip lock bag. If it’s a male the sperm is squeezed into the Solo container.
I thought about this – it sounded barbaric. Killing the fish to get the egg and sperm. All of this for a few sport fish and thousands of commercial fish.
The eggs I was looking at were from an anadramous fish species – the Red or Sockeye Salmon. Anadramous salmon begin their lives on gravel bars in fresh water lakes and streams. As they grow they move back down stream towards the ocean. Entering the ocean they are able to adapt to the new saltwater environment where zooplankton are there primary food. After several years in the open ocean they return to the stream of their birth – at least where they started as an egg.
Eggs are laid and sperm is spread in the water. The mother defends the spot where she laid her eggs from other fish, but a slow and deadly process begins. Once an anadramous fish enters the ocean an irreversible physiologic process occurs. They adapt and are able to live in the salty ocean water, but returning to the home stream to lay eggs they begin a slow, perhaps painful process of dying. Once back in the freshwater they will never return to the ocean again. After fertilizing or laying eggs they die where their lives began.
Perhaps harvesting eggs is not such a barbaric process after all.
All the trays were stacked high. In each cup a mixing stick had been inserted. Three people were standing at the counter. The first dumped eggs into the cup – each bag of eggs into its own cup. Once all the cups in the tray were filled with eggs it was passed on to the next person. She opened the little container and gave a dribble of sperm to each cup. Several containers of sperm were used to fertilize the eggs. Water was added to the cup. Then the stick was used to mix the eggs and sperm. Once mixed, the stick was discarded – a convenient way to remember which cup had been mixed but more importantly to prevent cross-contamination. Once all the cups in the tray had been mixed they were passed on to the next person.
He had a large wash basin filled with a deep red solution of benzoate. Each cup of eggs was dumped into a plastic strainer then rinsed with fresh water and the benzoate solution. The solution’s purpose was to harden the eggs and prepare them for incubation in the hatchery. In four to six months the fertilized eggs will start to show small, black eye spots. Unfertilized eggs will turn white. It was during this step I noticed a small white tag floating in the solution as the tray was carried away.
I asked about the tag. Normally the eggs are dumped into a large incubation vat, but today’s eggs were being treated differently. Fish populations get sick. A tissue culture had been taken from each fish harvested for eggs. The tissue was being sent to the state fishery lab where the pathologist would culture it to determine the level of bacteria present in the specimen. The results will then be sent back to the hatchery where depending on the culture results they must determine if they can continue to raise or must destroy the eggs.
Being naturally inquisitive, I had to know if the process they were doing today was time sensitive.
The answer, “The eggs are viable for several days, but the sperm, even after we add a saline solution to preserve it, only last a few hours.”
The water for the fish hatchery comes from an aquifer in the mountain. The water comes out of the well at about 3-7 degrees C. That is cold water. The cold water actually causes the fish to grow slowly. Right now the lake and stream water is 10-15 degrees C but during the winter – much of the year – the lakes are frozen and the water temperature hovers near 0 degrees C. With the ice cover there is almost no oxygenation occurring. In the hatchery they have a room with where the ceiling is about thirty feet high. Just like in a home aquarium the water must be aerated. The water is pumped to the top of the room then cascades down a series of shelves which oxygenates the water. Even with the low annual water temperature from the aquifer the hatchery fish are able to grow faster over time than they would in nature.
Water, a well – How much water do they use? 3,000,000 gallons per day. None of that water is recycled – though in some places it is. Fish carry a virus that is lethal in hatcheries. If a very expensive filtering and treatment system is not in place the fish contract the virus. During the spring, winter, and fall the water supply is not a problem. Natural recharge keeps the aquifer full, but during the winter recharge slows. It is cold and everything is frozen. By spring they are nearing the dredges of what the aquifer can supply.
It is water that limits fish production at the hatchery.
