EAST MACHIAS, Maine — About 14,000 new residents of Washington County made their debut Tuesday as they were poured, one bucket after another, into a tributary of the East Machias River.
They are among the 200,000 young salmon being released into the wild this month by Downeast Salmon Federation as part of its effort to restore the river’s salmon population. Since 2012, when the group started introducing juvenile salmon, called parr, into the river, it has released more than half a million of the fish into the wild after raising them at a hatchery on Willow Street.
“We’re hoping to saturate the river with salmon in hopes that they come back and populate the river on their own,” said Kyle Winslow, the federation’s hatchery manager and outreach director.
Atlantic salmon in Maine rivers, where they were abundant before World War II, have been listed as endangered by the federal government since 2000. Dam construction, poor water quality, climate change, development near the rivers and invasive species have all played a role in the species’ decline.
In 2011, the North Atlantic Salmon Fund, based in Iceland, contacted the Atlantic Salmon Federation in Calais, looking for an opportunity to fund a salmon-stocking effort in Maine. That led the Icelandic organization to the Downeast Salmon Federation, which introduced its first parr into the East Machias River watershed in the fall of the following year.
The local group, which has its headquarters in Columbia Falls, raises parr from eggs that it gets from the Craig Brook National Fish Hatchery in Orland, which is run by the U.S. Fish and Wildlife Service. At the Down East hatchery, eggs are placed into trays and, after hatching, transferred into a wooden incubator box. From there, as they grow, the salmon make their way into larger tanks where they mature over a few months into the parr stage.
Before the parr are released, they are fitted with clips to identify them as having been reared at the East Machias hatchery. On Tuesday, 14,000 were trucked in tanks and coolers with circulating water to Beaverdam Stream off Route 9, about an hour’s drive away.
Several University of Maine at Machias students helped carry the parr in 5-gallon buckets from trucks to the East Machias River tributary. The students then gently poured the young fish into the chilly flowing water.
Winslow said including Machias students in the stocking effort is a way to get the community invested in salmon’s recovery.
“We really try to get as many students through [the hatchery] as we can, to reconnect them with these fish,” Winslow said.
The techniques used at the hatchery were developed in England by biologist Peter Gray, according to Winslow. As manager of the Kielder salmon hatchery on RiverTyne, Gray instituted innovations such as using untreated and unfiltered river water and keeping the juvenile fish in dark-colored tanks with flowing currents.
The dark color, according to Winslow, mimics the natural dark bottom of the river and triggers chromatophores in the skin of the fish to blend in. The current in the larger tanks prompts the fish to swim against it, which keeps them physically fit and discourages them from nipping at each other. This conditioning, he said, gives the fish a better chance of surviving once they get introduced into the river.
“What we’re trying to do here is raise juvenile salmon in as much of a natural environment as we can in an unnatural setting like a hatchery,” Winslow said. “Basically, we’re hoping to stock fish that are fit to survive in the river as they would if they were naturally reared in the river.”
Winslow said that Gray, who died in 2013, told federation staffers that the goal of the hatchery should be to raise baby salmon alevins into “‘athletes” before releasing them.
“The whole goal is to have these fish migrate out into the ocean and come back [in a couple of years] as big adult salmon to spawn and repopulate the rivers on their own,” he said. “If we do a good job, then we’ll put ourselves out of a job here at the hatchery.”
The hatchery manager said that the federation has done surveys in the river and found densities of maturing salmon that suggest the stocking effort is working. He said they have not yet found any adult salmon from prior stocking years that have returned from the ocean, but that staff members will go out in the next several weeks to look for “nesting” sites in the river, which would indicate that adult fish have returned and are spawning.
“This would be the first year [for returning adults],” Winslow said. “We’re seeing early successes. … We’re really excited about the next five years of the project.”