Juneau Empire –
Standing next to “Colossal,” one of the beaver dams in the Dredge Lakes area, it’s not hard to imagine how difficult it is for coho salmon to traverse. The dam barricades off all but a narrow strip of a slough east of Dredge Lake, where water passes over a two-foot-high waterfall.
Dams act as both a positive and negative for coho salmon, which swim through the middle of the beaver habitat to spawn in nearby Powerline Creek, said U.S. Forest Service fisheries biologist Jake Musslewhite. Using radio telemetry, an animal tracking method using radio signals, Musslewhite tracked five spawning salmon this fall. He found obstacles like dams significantly thwarted salmon’s progress to Powerline Creek.
Musslewhite thinks it’s the first radio-telemetry study conducted in the area.
“All these ponds actually make great rearing habitat, so it’s a good place for little baby coho to grow up,” he said. “But you need the adult coho to make those little baby coho in the first place. So they have to get over those beaver dams all the way back up to the base of the mountain there.”
Musslewhite led the Empire on a hike on Wednesday morning to the dam site, only about a 15-minute walk from the Juneau Ranger District office.