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Oregon Tests Hatchboxes to Reintroduce Chum Salmon in Clatskanie River
State fishery managers are using a small, streamside incubation system to help bring chum salmon back to a tributary of the Clatskanie River in northwest Oregon.
ODFW recently installed a hatchbox system along the stream in an effort to reintroduce chum salmon to the watershed. The project was first reported by Oregon Public Broadcasting.
The system consists of six large barrels, three that filter stream water and three that hold trays of fertilized salmon eggs. As water flows through the boxes, it keeps the eggs oxygenated while protecting them from predators.
When the eggs hatch, usually in January, the young fish are flushed directly into the stream.
Tom Stahl, a fish biologist with ODFW, said hatchboxes are a cost effective way to boost salmon numbers in waterways that no longer support wild runs.
“There are no chum here,” Stahl said. “We want to reintroduce them. This gives us a way to do that without impacting existing wild fish.”
Hatchboxes were once common across Oregon and were frequently used in schools to teach students about the salmon life cycle. Their use declined over the years as concerns grew about hatchery fish competing with wild salmon and the fact that hatchbox fish are released at a much smaller size than those from traditional hatcheries.
A chart produced by NOAA Fisheries demonstrates how few salmon survive from egg to adulthood, with an estimated two spawners emerging from 3,000 eggs
aAnother concern is that hatchbox fish are not marked, meaning they cannot be distinguished from wild salmon once they return to spawn.
Still, tribal leaders and state officials say hatchboxes can play a role in areas where salmon runs have nearly disappeared.
Brenda Meade, chair of the Coquille Tribe, said drastic declines in fall Chinook returns forced managers to consider every available tool. Returns on the Coquille River dropped from roughly 10,000 fish in 2017 to just three brood pairs by 2020.
“They were calling it near extinction levels,” Meade said. “It was devastating.”
Multiple factors contributed to the decline, including warming water temperatures, low flows, poor habitat and changing ocean conditions. One major issue was the introduction of smallmouth bass into the watershed, a predator known to consume juvenile salmon.
In response, the tribe and its partners began removing bass using electrofishing boats and incentive based fishing derbies.
A section of the Clatskanie River near Astoria, where hatchboxes are being used to incubate chum salmon eggs before they hatch and enter the stream
The Oregon Legislature also took action this year by passing Senate Bill 221, which directs ODFW to encourage and study new hatchbox projects in Coos County. While the Clatskanie hatchbox is not part of that bill, ODFW plans to monitor results as similar projects move forward.
Stahl said the goal is to evaluate whether hatchboxes can meaningfully increase salmon returns over time.
“These fish will be out in the ocean for several years before they return,” he said. “It’s going to take patience, but we’ll be watching closely.”
The post Oregon Tests Hatchboxes to Reintroduce Chum Salmon in Clatskanie River appeared first on OutdoorHub.
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Oregon Tests Hatchboxes to Reintroduce Chum Salmon in Clatskanie River
State fishery managers are using a small, streamside incubation system to help bring chum salmon back to a tributary of the Clatskanie River in northwest Oregon.
ODFW recently installed a hatchbox system along the stream in an effort to reintroduce chum salmon to the watershed. The project was first reported by Oregon Public Broadcasting.
The system consists of six large barrels, three that filter stream water and three that hold trays of fertilized salmon eggs. As water flows through the boxes, it keeps the eggs oxygenated while protecting them from predators.
When the eggs hatch, usually in January, the young fish are flushed directly into the stream.
Tom Stahl, a fish biologist with ODFW, said hatchboxes are a cost effective way to boost salmon numbers in waterways that no longer support wild runs.
“There are no chum here,” Stahl said. “We want to reintroduce them. This gives us a way to do that without impacting existing wild fish.”
Hatchboxes were once common across Oregon and were frequently used in schools to teach students about the salmon life cycle. Their use declined over the years as concerns grew about hatchery fish competing with wild salmon and the fact that hatchbox fish are released at a much smaller size than those from traditional hatcheries.
A chart produced by NOAA Fisheries demonstrates how few salmon survive from egg to adulthood, with an estimated two spawners emerging from 3,000 eggs
aAnother concern is that hatchbox fish are not marked, meaning they cannot be distinguished from wild salmon once they return to spawn.
Still, tribal leaders and state officials say hatchboxes can play a role in areas where salmon runs have nearly disappeared.
Brenda Meade, chair of the Coquille Tribe, said drastic declines in fall Chinook returns forced managers to consider every available tool. Returns on the Coquille River dropped from roughly 10,000 fish in 2017 to just three brood pairs by 2020.
“They were calling it near extinction levels,” Meade said. “It was devastating.”
Multiple factors contributed to the decline, including warming water temperatures, low flows, poor habitat and changing ocean conditions. One major issue was the introduction of smallmouth bass into the watershed, a predator known to consume juvenile salmon.
In response, the tribe and its partners began removing bass using electrofishing boats and incentive based fishing derbies.
A section of the Clatskanie River near Astoria, where hatchboxes are being used to incubate chum salmon eggs before they hatch and enter the stream
The Oregon Legislature also took action this year by passing Senate Bill 221, which directs ODFW to encourage and study new hatchbox projects in Coos County. While the Clatskanie hatchbox is not part of that bill, ODFW plans to monitor results as similar projects move forward.
Stahl said the goal is to evaluate whether hatchboxes can meaningfully increase salmon returns over time.
“These fish will be out in the ocean for several years before they return,” he said. “It’s going to take patience, but we’ll be watching closely.”
The post Oregon Tests Hatchboxes to Reintroduce Chum Salmon in Clatskanie River appeared first on OutdoorHub.
Continue reading...