11-11-2004, 02:57 AM
North Dakota Game and Fish Department fisheries personnel have concluded another successful salmon spawning effort, reports Jason Lee, fisheries biologist, Riverdale.
Spawning crews at Lake Sakakawea caught more than 2,000 fish over the past several weeks, of which 36 percent were females. "We had an excellent year," Lee said. "We had a goal of collecting 1 million eggs for our stocking needs and took over 1.7 million good eggs."
The female salmon averaged 6.0 pounds this year, compared to 6.2 in 2003. The fish were collected in a spawning ladder and by electrofishing. Eggs collected from fish that ascend the spawning ladder are typically better quality than eggs collected by electrofishing.
The spawning ladder is a 60-foot-long, four-foot-diameter culvert containing a series of baffles. The baffles create pools (steps) where salmon stage or rest as they swim to the top of the ladder. The ladder is set up perpendicular to the shoreline and is typically supplied with water 24 hours a day while the salmon are spawning. The ladder simulates a flowing stream, thereby attracting spawning fish.
While the egg take was excellent, fisheries biologists are concerned about the future of Sakakawea's salmon fishery. "The main concern is the forecast for Lake Sakakawea's water elevation next year and the negative effects low water can have on the populations of salmon and their main forage, smelt," Lee said.
Chinook salmon begin their spawning run in October into bays on Lake Sakakawea's eastern end. Because of low water, this year the spawning ladder was set up at the main boat ramp in Lake Sakakawea State Park. Since salmon cannot naturally reproduce in the lake, game and fish and Garrison Dam National Fish Hatchery personnel collect and fertilize eggs and transport them to the hatchery.
Once the eggs hatch, young salmon spend several months in the hatchery before they are stocked in Lake Sakakawea. Surplus eggs will go to South Dakota and Montana.
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Spawning crews at Lake Sakakawea caught more than 2,000 fish over the past several weeks, of which 36 percent were females. "We had an excellent year," Lee said. "We had a goal of collecting 1 million eggs for our stocking needs and took over 1.7 million good eggs."
The female salmon averaged 6.0 pounds this year, compared to 6.2 in 2003. The fish were collected in a spawning ladder and by electrofishing. Eggs collected from fish that ascend the spawning ladder are typically better quality than eggs collected by electrofishing.
The spawning ladder is a 60-foot-long, four-foot-diameter culvert containing a series of baffles. The baffles create pools (steps) where salmon stage or rest as they swim to the top of the ladder. The ladder is set up perpendicular to the shoreline and is typically supplied with water 24 hours a day while the salmon are spawning. The ladder simulates a flowing stream, thereby attracting spawning fish.
While the egg take was excellent, fisheries biologists are concerned about the future of Sakakawea's salmon fishery. "The main concern is the forecast for Lake Sakakawea's water elevation next year and the negative effects low water can have on the populations of salmon and their main forage, smelt," Lee said.
Chinook salmon begin their spawning run in October into bays on Lake Sakakawea's eastern end. Because of low water, this year the spawning ladder was set up at the main boat ramp in Lake Sakakawea State Park. Since salmon cannot naturally reproduce in the lake, game and fish and Garrison Dam National Fish Hatchery personnel collect and fertilize eggs and transport them to the hatchery.
Once the eggs hatch, young salmon spend several months in the hatchery before they are stocked in Lake Sakakawea. Surplus eggs will go to South Dakota and Montana.
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