This spring’s high flows along the Boise River have impacted many areas where fish go to spawn. Idaho Fish and Game says this year’s flooding will have both short-term and long-term implications on the river.
Fish and Game expects fish reproduction this year to be down as the high flows disturbed a lot of the spawning beds. However, in the long term, the flooding has created new ones.
Every year, the Boise River sees as many as 30,000 fisherman, who spend 100,000 hours casting their lines.
“We describe it as one of the best urban trout fisheries in the country,” regional fisheries manager Joe Kozfkay said.
Aaron Wardell is one of those anglers who spends almost every day on the river banks. He knows the river well, but this year things are a little different.
“Yeah, I've caught fish this year in places that I never thought I would,” Wardell said.
Months of flooding not only changed the river’s path, but also where fish spawn.
“Although, the river moved a lot of fine sediments out, it probably also moved out some spawning-size gravel and so we think maybe there's some possibly negative consequences there,” Kozfkay said.
Kozfkay believes the Boise River probably will see some decreases in fish reproduction this year. However, next year could be a different story.
“We have new soils exposed and once cottonwoods have seeded out, which they already have, we think we're going to get really good cottonwood recruitment, which doesn't happen in a normal year,” Kozfkay said.
The high flows also have created more spawning grounds downriver.
“We lost a bank, that creates instability, but it also provides some new gravel for the river,” Kozfkay said.
Gravel that fish can use next year to spawn.
“That diversity in flow creates diversity in habitat, which is good for fish in the river,” Kozfkay said.
So if you have that one spot you’ve fished for years.
“There's a couple spots that I keep secret,” Wardell said.
You may have to find a new one.
“It might be deeper, it might have filled in, it may not have as much cover, it may have more cover," Kozfkay said. "So it's a new river that that's the fun part of fishing the river.”
Idaho Fish and Game plans to do a fish survey this fall. Once they’ve completed that, they’ll see what kind of impact this year’s flow had on fish reproduction.