YUBA RESERVOIR — Fishery managers have always faced an uphill battle at Yuba Reservoir. With recent drought conditions, changes in water usage and habitat degradation, however, that job has become even more difficult.

"(Managing Yuba has) been difficult when we had water," Mike Slater, the Utah Division of Wildlife Resources central region sportfish project leader, said. "We've been working on Yuba for 25 years. Water's always been somewhat of an issue, but at least we had something to work with. Now, it's even more difficult."

Water issues

Yuba has long been a popular sport fishery. Located just north of Scipio, it's a large lake with plenty of room to grow trophy fish. The current state record northern pike was caught at Yuba in 2013. It weighed just over 26 pounds and measured 45.5 inches long.

But pike haven't always been the desired quarry at Yuba. For years, it was known as one of the better walleye fisheries in the state. According to Slater, that began to change in 2003, when the pike population really took off.

"When it refilled in 2003, the pike just exploded," Slater said. "I don't know if it was just because of the extra vegetation, but I think the (pike) just won out because of the way the water was drawing down and coming up."

The pike thrive there because they benefit the most from the unpredictable water levels in Yuba Reservoir, according to Chris Crockett, DWR central region aquatics manager. In the spring, as the reservoir fills with snowmelt, pike are able to successfully spawn. Once the need for irrigation water arises, the water levels drop quickly.

"You've got rising water when those pike are spawning," Crockett said. "And then they (water users) start drawing it down pretty fast about the time that the walleye start to spawn. It just ends up, at least for the spawn, disproportionately benefiting the pike. Nothing else pulls off a successful spawn."

However, those fluctuating water levels are the real problem fishery managers have to solve at Yuba. The long drought over the past decade has caused water users who draw from Yuba to take more from a dwindling supply.

Both Crockett and Slater noted that the water draw from the reservoir is something the DWR has always worked around when managing Yuba. The reservoir's primary use is irrigation, and the Division of Wildlife Resources doesn't own water rights at the lake. Fishery managers have always worked with that reality in mind and have maintained a great relationship with water users over the years.

With drought now such a large factor in the fishery management, though, there's only so much wildlife officials can do in a lake where they don't own water rights.

"We're not saying anything against water owners," Slater said. "They own every drop of that water. It's just that all of a sudden, we're being faced with a different management scenario."

Fish management

In light of low water realities, the wildlife agency faces tough choices to effectively manage Yuba as a sport fishery. Anglers have been vocal about wanting a walleye fishery re-established, while others enjoy the opportunity northern pike present.

In its current state, though, Yuba likely can't support both fisheries. On top of water levels affecting the spawn, the lake doesn't have the habitat and forage needed to maintain a walleye fishery.

"We know we don't have a lot of forage in (Yuba)," Crockett said. "Northern pike are an issue, no doubt."

Pike are voracious predators, and anglers and biologists alike have noted sharp declines in walleye and yellow perch populations. Wildlife biologists have tried planting perch into the lake, but it hasn't proven effective yet.

"We've already moved or stocked hundreds of thousands (of perch)," Crockett said. "We're looking at the option to beef up (yellow perch stocking). That's about $250,000 a year. We've really started re-evaluation whether we can justify spending the anglers' dollars on that."

One option is to remove northern pike from Yuba completely. That would allow for more species to coexist, though they'd all face spawning challenges due to water levels in the lake. Not to mention that the cost of removing pike is high.

"We're talking $250,000 - $300,000 just for rotenone product," Crockett said. Rotenone is the chemical used to kill unwanted fish in water bodies across America.

The solution

These problems culminated in fisheries managers deciding to, "take a step back and come up with some scenarios that aren't high risk, high dollar," according to Crockett.

What that means in the short term is that the DWR will use more of what they call "excess/bonus fish" to supplement Yuba's populations. These are fish raised in state hatcheries that, for one reason or another, don't meet requirements to go into a specific water body.

Crockett cited the recent planting of nearly 300,000 walleye as an example of bonus fish use. According to Crockett, those walleye didn't meet the requirements for the state's triploid fish program. Triploid fish are genetically modified to be sterile, enabling biologists to more effectively manage fish populations. Triploid brook trout are currently being used to control brook trout reproduction on Boulder Mountain, to great success.

"Right now, that's what we're looking at, is opportunity to use bonus fish, until or if we get that water shored up, to see if we can still provide that fishery," Crockett said.

The long-term future of Yuba remains up in the air as fisheries managers have to adjust their plans for a prolonged drought, or the possibility that current precipitation levels are the new normal here in Utah.

For more information about Yuba State Park, visit Utah.com.

Related topics