Wyoming’s captive golden trout broodstock program
Golden trout are not native to Wyoming, but they’ve been in the state for more than 100 years. These colorful fish are native to high-alpine waters in California, and over the years golden trout were stocked in high-alpine lakes around the Cowboy State. Since 1985 the Wyoming Game and Fish Department has stocked 88 different waters with golden trout.
A big reason why Wyoming has a sustainable golden trout fishery is because the Story Fish Hatchery is home to the only genetically pure strain of captive golden trout broodstock in the world. Instead of gathering eggs in the wild, personnel at Story raise adult fish to spawn. Story is Game and Fish’s primary broodstock facility. It also houses broodstocks for brook, brown, rainbow and lake trout.
The reason for broodstocks of any species is two-fold.
“Going out in the wild to collect eggs can be unreliable from year-to-year,” said Steve Diekema, Story Hatchery superintendent. “You have to time it right and catch the females when they are ready to release their eggs.
“Second, which is our biggest issue now, is you never know the disease status of the fish in the wild. We do test them each year, but you never know what can happen. Sometimes a disease could pop up and you don’t want to bring that into any of our facilities. If we can keep our fish contained in a captive broodstock we can eliminate those two issues.”
A little history
Golden trout eggs from the Sierra Nevada Mountains in California were first brought to Wyoming in 1920 by the U.S. Forest Service.
Game and Fish gathered golden trout eggs in the wild from the 1920s through the early 1990s. It got the fish and eggs from lakes in Sublette County. A fire in the late 1980s in the upper Surprise Lake drainage eventually forced Game and Fish to abandon egg collection. Three attempts were made to create wild broodstocks after that, but all failed.
Story is Wyoming’s oldest fish hatchery. It opened in 1909 and it’s gone through several renovations. One of the most significant started in 2005 when it went through the conversion of a production facility where it grows and stocks fish, to a broodstock facility where it spawns broods and provides eggs to other facilities to raise and stock.
In 2007 golden trout eggs from Sylvan Lake in Montana were shipped to Story, and the facility successfully spawned captive golden trout in 2009.
During those early years, Story produced just enough golden trout eggs to meet in-state needs — around 40,000 eggs per year. In 2022 it produced about 300,000 and for the better part of a decade has sent eggs to other states. This year eggs were sent to Colorado, Idaho and Washington. In recent years Story also has sent eggs to California, Montana and Utah.
“When I look back at the first couple of years we had just enough eggs to provide for Wyoming,” said Diekema, who has worked at Story for 14 years. “As we built the population up and became better at what we were doing we started shipping eggs to other states.”
How it works
Golden trout — along with brook, brown and rainbow trout — become sexually mature at 3-years-old. Diekema and his crew spawn males and females that are 3-and 4-years-old, and sometimes some females are held until they are 5 to bolster egg numbers.
Two age classes are always spawned together. For example, a 3-year-old female with a 4-year-old male. That ensures there is not a brother-sister cross. Producing eggs and fish is a top goal, obviously, but so is genetic integrity.
“We want to produce enough good-quality eggs, but when you back it all the way out it’s all about broodstock management first. Then, everything else falls into place,” Diekema said.
The spawn takes place over about a five-week period. To gather a genetic snapshot, the crew takes eggs from the middle 60 percent of the eggs during the spawn, which consist of 150 male-female pairs.
“A geneticist will say 25 pairings is how you maintain your broodstock. We times it by as much as 10 depending on the species to cover our bases,” Diekema said.
Once the golden trout eggs are gathered they’re eventually shipped to the Ten Sleep Hatchery. All of the golden trout fish at Story are kept in tanks and separated into age classes before and after the spawning process.
All about the water
The water supply to the Story Hatchery, and specifically the water temperature, is a big factor in the golden trout broodstock program’s success. The facility is supplied by water from South Piney Creek.
“That water is super-cold for six to seven months a year,” Diekema said. “Starting in late October the water temperature drops below 40 degrees and doesn’t climb back above 40 again until May. Around August it tops around 55 degrees and then drops down.”
Those types of water temperatures are similar to the golden trout’s native territory in California, along with the water in Wyoming’s alpine lakes and streams.
“That’s probably a similar profile from their native waters,” Diekema said.
Diekema doesn’t think the golden trout broodstock program would work if it were not for the water temperature at Story. In fact, attempts at other Game and Fish hatcheries such as Daniel and Boulder, along with Como Bluff near Laramie that is now closed, attempted to create a golden trout broodstock, but fish didn’t produce quality eggs when they became adults. Diekema said he thinks that’s because the water temperatures at those facilities were consistent and not fluctuating because their sources were from springs. That doesn’t mean other broodstocks can’t be raised in those situations, but it isn’t advantageous for golden trout.
“Based on Story’s water temperature and timing, it mimics what happens in nature for golden trout,” said Andrew Nikirk, Game and Fish fisheries biologist in the Sheridan Region.
Golden trout in Wyoming can be found in high-alpine lakes in the Wind River, Bighorn, Snowy Range and Beartooth mountains, along with a handful of lakes on the south end of the Absaroka Mountains. Game and Fish also stocks goldens in some easier-to-get-to waters around the state for people to have an opportunity to catch them.
High-alpine lakes are stocked on two- or four-year rotations, and 90 percent of the waters in Wyoming stocked with golden trout are done via helicopter. This year 19 lakes were stocked in the Bighorn, Snowy Range and the east side of the Wind River mountains. Nine of those lakes were on the Wind River Indian Reservation. Seventeen lakes were stocked in 2021 in the Beartooth Mountains, south Absarokas and the west side of the Wind River mountains.
Kris Holmes, Game and Fish spawning coordinator, said going back to 2018 as many as 32 lakes were stocked with golden trout in a single year, and as few as 14. He said alpine lakes in the Snowy Range were not stocked this year because a hail storm damaged the helicopter, but golden trout were stocked in Big Brooklyn Lake that was accessible with a stocking truck.
The world-record for golden trout was caught in Wyoming at 11 pounds in 1948. More recently, the all-tackle length world record 53-inch golden trout was set in 2012 at appropriately named Golden Lake in the Wind River Mountains in 2012 according to The International Game Fish Association.
Last year two line-class IGFA world records for golden trout were broken at waters on the east side of the Wind River Mountains. One of those was the “Smallfry” world record for anglers less than 10-years-old. A 4-year-old girl landed a 2-pound golden.
But while fishing for golden trout is good in Wyoming, it also is a good time to manage the species.
“I think it is the golden age of golden trout fishing right now,” said Paul Gerrity, Game and Fish fisheries biologist in Lander. “Now that golden trout stocking is full-go because of our culture system, I can try to do more fine-tune management. We can fine-tune stocking strategies to give anglers opportunities to catch a lot of goldens, or opportunities for bigger fish and how often we should stock certain waters.”
It’s cool to claim Wyoming is the only place in the world that raises a genetically pure strain of golden trout. Ironically, Diekema said California showed interest in starting its own genetically pure broodstock program with fish from Wyoming. Eggs were shipped to California, but a flood wiped out the resulting fish at the facility.
Not only does Wyoming raise and stock genetically pure strains of golden trout, it provides eggs of those same fish to other states.
“Maybe Wyoming has the most golden trout in the country,” Diekema wondered. “It’s also cool when we have visitors from other states and can say ‘if you caught a golden trout in Colorado, it probably came from these tanks right here.’ To think this little facility at Story is supplying the golden trout programs of states like Colorado, Idaho, Washington and Wyoming, that’s cool to think about.
“This program wouldn’t be a success if it weren’t for all the different employees that dedicated themselves to making this happen. As custodians of Wyoming’s resources we take pride in what we have accomplished for the people in the state of Wyoming.”
That resource may be the future for golden trout throughout the West, and especially in the golden trout’s native territory.
“With drought conditions and a lack of moisture in California where golden trout are native, you can look at our high-alpine lakes as a genetic refugia — a location which supports an isolated or relict population of a once more widespread species — in case those populations are lost in their native range. That’s really cool to think about,” Holmes said.