Nevada tribes saving Lahontan cutthroat trout from extinction
(Nevada Current) Thousands of captive-raised specimens of the largest cutthroat trout species in North America are released into Pyramid Lake every year, but despite the trout’s size and might, they are also one of the most threatened.
Decades of overfishing, dam building, water diversion, and other human actions have set the Lahontan cutthroat trout up for unrelenting population decline.
Populations of the threatened Nevada fish have only continued to decline in the last decade, according to a recent review by federal wildlife managers.
A new status report released by the U.S. Fish and Wildlife Service (FWS), determined that only five of 71 populations of Lahontan cutthroat trout are considered resilient, and less than half are likely to be resilient into the future.
But within the rows of troubling data on the steady decline of the native trout is one compelling detail: two of the most resilient populations of Lahontan cutthroat trout are managed by the Pyramid Lake Paiute Tribe and the Summit Lake Paiute Tribe.
In fact, the largest and most resilient population of the trout across the entire Great Basin is in Summit Lake, located entirely within the Summit Lake Reservation.
Missing from the FWS report are details of the work both the Summit Lake Paiute Tribe and the Pyramid Lake Paiute Tribe have done to preserve the trout and its habitat for decades, if not centuries – an omission that, tribal officials say, is another footnote in a long history of government agencies sidelining tribes.
“They say we’re partners, but they made no mention of Pyramid Lake Fisheries. They made no mention of what we do here with respect to the Lahontan cutthroat trout,” said Mervin Wright, the executive director of Pyramid Lake Fisheries. “We’ve been doing this year in and year out for the last 41 years, and it’s been successful.”
The data bears that out, at least according to the FWS status report.
The resiliency of the Pyramid Lake Lahontan cutthroat trout population, however, is not self-sustaining. The tribe manages a fish hatchery where the trout are spawned and raised as juvenile trout until they can be released into the lake.
Lahontan cutthroat trout are obligate fresh-water spawners, meaning their eggs can’t survive naturally in Pyramid Lake’s salty waters.
Less than 11% of the stream-dwelling trout are self-sustaining, meaning they don’t need to be supplemented with hatchery-raised fish, while just 0.4% of lake dwellers are self-sustaining, according to the U.S. Fish and Wildlife Service.
A century ago, swarms of Pyramid Lake fish would swim far up the Truckee River to safely lay their eggs in the pebbly bottoms of the freshwater river. But a badly planned diversion dam on the river blocked the trout from their native spawning grounds, making the trout functionally extinct from Pyramid Lake by the 1940s.
The Derby Dam was completed in 1905, and diverted half of all Truckee River water to agricultural fields near Fallon, greatly destabilizing the lake and its inhabitants. By 1967, Pyramid Lake dropped by an estimated 80 feet.
Lahontan cutthroat trout is one of a few species of trout native to Nevada and inhabited the ancient Lake Lahontan and its tributaries during the ice ages until the lake shrank to remnants like Pyramid Lake about 7,000 years ago. The Summit Lake Paiute Tribe and the Pyramid Lake Paiute Tribe have a deep cultural connection to the trout.
Large trout populations in both lakes helped sustain the Paiute people once the reservation system was created to cut them off from their traditional homelands and food sources.
How long the trout were truly missing from their home in Pyramid Lake is a question Wright still asks himself.
“We have stories here about my father’s generation, my grandfather’s generation, catching Lahontan cutthroat trout from 1940 to 1960 at Pyramid Lake, but that story was never heard,” Wright said. “Pyramid Lake is a huge lake. It’s hard to believe that someone came out here and surveyed every square foot every cubic yard of this lake and determined there’s not one trout left in this huge body of water.”
What’s always been clear to Wright, however, is that without more water for Pyramid Lake the trout had no chance of survival.
‘It’s because of the tribe’
After a long struggle involving numerous court actions, the Pyramid Lake Paiute Tribe was able to negotiate water allocations with the federal government and protect the lake and fish under the Endangered Species Act of 1967 and the renewal of the Clean Water Act of 1987.
By 1991 the Truckee River Settlement Act was approved by Congress, and required the tribe to be consulted in all decisions involving the Truckee River water. It was another decade before government officials and the tribe reached an operating agreement to manage Truckee River reservoirs. After being whipped out, the Lahontan cutthroat trout successfully spawned in the short stretch of river between Pyramid Lake and Derby Dam for the first time in 80 years in 2012.
“The tribe has secured water, all of the water that is flowing to Pyramid Lake, it’s because of the tribe. The tribe had done all of this work to secure the water that flows to Pyramid Lake,” said Wright, who helped negotiate the operating agreement as the former chairman of the Pyramid Lake Paiute Tribe.
Summit Lake, home of the most resilient population, is free of water diversions which the tribe fought to prevent, leaving Mahogany Creek clear for spawning trout. The lake is also closed to non-tribal members, while tribal members are limited in how many fish they can catch.
Not all populations of the threatened trout have been so lucky.
The Lahontan cutthroat trout population living in the North Fork of the Humboldt River have avoided hybridization with non-native fish, but gold mining activities in the watershed have degraded water quality, pelting the fish with toxic chemicals, according to a FWS study. Mining near the North Fork of the Humboldt River has also lowered groundwater levels in the basin due to water removal for construction, severely impacting the trout population.
For these less resilient populations, FWS is looking to develop a genetics management plan to better understand the current genetic health of the trout and how to improve it, including creating gene flow between isolated populations, said Sean Vogt, the Lahontan Cutthroat trout recovery coordinator for the FWS. The agency included a proposal to complete a full genetic assessment of all trout populations in the Great Basin as part of their long-term plan.
“The opportunity to improve the status of Lahontan cutthroat trout is present here, and that is not the case for many species in the West. It is possible to move the species in a positive direction and reverse a declining trend by focusing on those populations,” said Vogt. “These tools will provide the foundational knowledge necessary to prioritize where and how partners focus recovery efforts in the coming years and should improve conservation outcomes prior to the next status review. ”
Wright said he thinks the FWS solution is misguided.
“The Fish and Wildlife Service stated they want to use genetic management with a recovery method. They need to work on restoring the habitat and use the natural system, let nature do the selection,” Wright said.
Freshwater fish are particularly vulnerable to population collapse due to their proximity with humans and their limited habitat which is routinely modified, said Wright. For a reintroduction to succeed in the long term, Wright explained, the habitat must be healthy enough to support the fish. He argues that a better use of FWS funding would be to look into emerging contaminants in the Truckee River.
“In the time before humans — the fish and the birds, the plants and the insects — they were the ones that controlled life. They were the ones that controlled survival. Then we came along as humans, we had to learn from them. And we did. But fast forward to today, and I wonder what happened,” Wright said.
Tackling greater threats to the trout like habitat degradation, pollution, climate change, and urban development is much more difficult, said Wright, but it’s the only realistic solution.
“Whenever man tries to control nature, man loses and nature is damaged,” Wright said.
You don’t have to look any further than Derby Dam, he added.