Re-introduction of Lahontan cutthroat trout displacing rainbow trout at Fallen Leaf Lake
By Kathryn Reed
It may come down to Lahontan cutthroat trout vs. rainbow trout. And if the Lahontan trout don’t take hold and the rainbow is basically eradicated, there may be no fish left.
That is the worst-case scenario for Fallen Leaf Lake and Glen Alpine Creek. It’s also one the U.S. Fish & Wildlife Service is not talking about.
When directly asked Wednesday night at the El Dorado County Fish & Game Commission meeting, the feds didn’t have an answer to what happens if the Lahontan are not successfully reintroduced to this water body.
“Never did we hear until this year that the long-term goal would be to not have rainbow trout. We were assured of the cohabitation of rainbow, lake and Lahontan cutthroat trout,” Jane Mitchell, who lives most of the year at Fallen Leaf Lake, said during the May 29 meeting at the U.S. Forest Service office in South Lake Tahoe.
While a USFWS rep vehemently refused to say the goal is eradication of the rainbow trout, a fact sheet created by her agency asks and answers a question in such a manner that complete elimination is the presumed goal.
Why do all the rainbow trout have to be removed from Fallen Leaf Lake and Glen Alpine Creek?
• Rainbow trout are not native to the Tahoe basin
• LCT and rainbow trout are ecologically similar and will spawn together and hybridize
• Hybridization results in the loss of the native, lacustrine LCT delaying and creating additional challenges for the reintroduction and recovery program at Fallen Leaf Lake
• Rainbow trout currently occupy the same feeding level as LCT in Fallen Leaf Lake and their presence is slowing the growth rate of LCT
• Rainbows removed during the spawning season are donated to the food bank
• Data such as food habits, age, and reproductive maturity.
Source: USFWS
The U.S. Fish & Wildlife Service proposed the reintroduction of the native species to Fallen Leaf Lake in 1999, with the first stocking occurring in 2002. The plan from the start was to stock the lake with 30,000 to 50,000 Lahontan yearlings each year.
Jane Mitchell talks May 29 about how the information coming out about the Lahontan cutthroat trout program has changed, while Victor Babbitt listens. Photo/Kathryn Reed
This strain of the LCT is the Pilot Peak. It doesn’t exist outside the Tahoe area. And it’s on the federal threatened species list.
After researchers in 2012 documented spawning of LCT, they also realized this trout was breeding with rainbow. According to Lisa Heki with the USFWS, allowing crossbreeding to continue would eventually wipeout the LCT.
Two weirs have been installed in the creek in March – one near the mouth and one by the bridge at Stanford Camp – to separate the two species. The rainbows that are caught are killed to see what’s inside. The fillets are given to a food bank. So far this has only happened to a handful of rainbow.
The USFWS would not answer why the rainbow weren’t relocated to another section of Glen Alpine Creek or into Fallen Leaf Lake.
Tom Barnes, a local resident, said, “It sounds like you want to destroy the rainbow trout fishery. It sounds like there is no recovery plan if this doesn’t work.”
Even though the LCT have not had a presence in this area for about 100 years and the rainbow are well established, government policy is for the native to take precedence over the non-native.
Some in the room wanted the USFWS to set an end date for what everyone calls an experiment. An end date defining success or failure.
“I’m not going to go there at this point because we have not given them a fair opportunity,” Heki said.
Even though the project has been going on for a decade, Heki said much of the first five years was not effective and involved a lot of learning.
It surprised most people in the room that the area where the LCT spawn can still be fished. Working on getting a temporary ban or at a minimum placement of signs discouraging the practice was talked about.
Victor Babbitt, who is on the local fish and game commission and runs a fly fishing business in South Lake Tahoe, is most frustrated with the economics of the situation.
He believes the decimation of rainbow trout in the Fallen Leaf Lake area along with what has been done to other local fisheries has the potential to cripple the local fishing industry and cost the area millions in lost revenue. The revenue is from fishing expeditions, sales of fishing supplies and tourists just not coming to town.
The reintroduction program has cost taxpayers about $2.5 million to date.
No action was taken May 29, but it was agreed better communication between the USFWS and the community is needed.