On the trout trail: Scientists study Truckee River fish population | SierraSun.com

On the trout trail: Scientists study Truckee River fish population

You may have seen a group of anglers wading through the Truckee River last week, scooping up trout by the net-fulls.

These people weren’t fisherman reaping the river’s harvest, though, but rather California Fish and Game Department employees conducting a special fish population survey.

For three days last week, exceptionally low river levels made it possible for crews to survey three spots on the Truckee River, an area that wild trout program leader David Lentz has dubbed the “crown jewel of wild trout fishing.”

“This area is really a high priority for us,” Lentz said as he waded out into the river in a green wetsuit. “It’s an extremely important trout fishing river in the Sierra, as well as the state.”

According to Lentz, the main objective of the survey is to get a sense for the health of the fish population, as well as the river’s ecosystem as a whole.

“We can tell a lot just from the health of the fish,” he said. “It’s really a type of fishing management and helps us evaluate various angling regulations, as well see the impacts of angling.”

In order to conduct the survey, the team uses a special machine that creates an electric field in the water. At first the fish are attracted to the field, but as they swim closer, they’re stunned momentarily by it, creating the perfect opportunity for Lentz and crew to scoop them up into their large nets.

“Once we have the fish, we record their type, weight and measurements, before letting them go,” he said, as he stood over a large tan bucket packed to the gills with brown and rainbow trout and various other native species.

“We’ve seen a lot these neat little guys,” he said motioning to the small, spotted brownish creature flipping around on his palm. “This is a Paiute sculpin, a native fish of the Lahontan Basin that the big trout like to eat.”

Other fish the group catalogued included speckled dace, Tahoe mountain suckers and mountain white fish.

“We didn’t find any cutthroat trout here, but that was expected,” he said. “They’ve got a tough life up here competing with all of the rainbows and browns, which are superior competitors. They used to come up in this area to spawn, but once the river was diverted years ago, that really made a difference.”

“People have been working to shift the river back to its natural pattern and direction, but that takes a long time and is very difficult,” he said.

Lentz and others took samples in the area where East River Street dead ends below the new Highway 267 bypass, upstream of town of Highway 89 where Donner Creek comes into the river, as well as near the Glenshire Bridge.

“These are stations that we’ve done in the past, but not since around 1993,” he said. “We’re trying to get estimates on the number and size of the fish here so that we can compare them with populations throughout history. Ideally, we’d like to be able to do this about every five years, but we simply don’t have the resources for that.”

Although, the data collected has yet to be analyzed, Lentz said he was pleased with what he found in this sweep of the Truckee River.

“We’ve gotten several really nice looking brown trout,” Lentz said. “A couple of them filled this whole tub from nose to tail.”

“There’s definitely more fish, as well as bigger fish than we found when we did this back in 1993,” he added. “Back then, there had been a pretty significant period of drought that really affected the fish population. But this week, I’ve been really surprised with the numbers of big fish that we’ve found.”

Depending on the results of the study, which are likely to come out sometime after New Year’s Day, angling regulations could change – although, Lentz said that is unlikely.

He also added that he was thankful for all of the locals who volunteered their time to help out with the project this week.

“This community always really steps up when we need help and seems to have a genuine concerns for the environment.”