By JOHN O’CONNELL joconnell@journalnet.com
SODA SPRINGS — The Idaho Department of Fish and Game puts on a daily fireworks show from mid-April through the end of June just for the pelicans that come to feed on cutthroat trout migrating from Blackfoot Reservoir.
The pyrotechnics are part of a longstanding hazing program intended to scatter the birds, thereby giving the Upper Blackfoot River watershed’s embattled Yellowstone cutthroat trout population a fighting chance.
The effort is funded, in part, by a collaboration involving mining companies, ranchers, Trout Unlimited and the Idaho Department of Fish and Game, called the Upper Blackfoot Confluence. UBC leaders say their hazing efforts combined with investments in significant habitat improvements are starting to pay off.
After 20 years of hazing pelicans with firecrackers and other tools — the program also involves shooting up to 75 pelicans per year to scare off the pod — this was the first year in which no pelicans nested on islands within the reservoir.
UBC scientists have noticed an increasing trend of new trout hatching within key tributaries. Furthermore, more than 1,800 adult cutthroat were counted at a trap within the river near China Hat for a second consecutive year. It’s a dramatic recovery from the early 2000s, when the number of fish caught at the trap dipped to a low of 16.
Historically, pelicans nested on three islands within the reservoir, and cutthroat trout were easy pickings as they swam through a shallow reach of water known as “the Gauntlet” while migrating to spawning tributaries.
The hazing program continues, as pelicans still fly to feed at the Gauntlet, but they now nest at nearby Chesterfield Reservoir, explained Carson Watkins, regional fisheries manager with the Idaho Department of Fish and Game. Watkins believes the progress with the pelicans and the UBC habitat improvements have come in the nick of time, amid an extremely hot and dry season in which cutthroat will require cool and deep water with plenty of cover.
“The whole point of the work we’re doing is to try to make the system resilient to years like this where we’ve got prolonged drought and excessive heat,” Watkins said. The eventual goal is to trap at least 10,000 fish annually, Watkins said.
The UBC Formed a decade ago, the UBC partners have invested more than $2 million in habitat improvements within the Upper Blackfoot watershed. They’ve brought in another $2.3 million in matching funds from other partners, including state and federal agencies.
Phosphate mining companies that operate in the area — Bayer U.S., Nutrien, J.R. Simplot and Itafos — provide most of the funding. Itafos joined the group this year, pledging $25,000, which has increased the annual UBC budget to $275,000.
UBC facilitator Will Whelan said the funds have covered a host of projects to make the watershed cold, complex and connected. They’ve worked with irrigators to improve old irrigation diversions, adding fish ladders to restore fish passage to historic spawning tributaries. They’ve replaced road culverts that had long been barriers for spawning trout. They’ve excavated stream channels to make them narrower and deeper to lower water temperature, and they’ve restored other sections of stream to their original channels. They’ve also planted hundreds of willow trees to shade the water and provide cover for the trout.
“We’re seeing signs of progress, but that good news is balanced with the real challenges here with high temperatures and low flows,” Whelan said. “Yellowstone cutthroat trout need cool water to survive. This is going to be one of those challenging years for us.”
Trout Unlimited biologists Warren Colyer and Jim Derito oversee the projects.
Redds During a June survey, Colyer said researchers counted an impressive 250 trout redds within the Upper Blackfoot tributaries in which the UBC has made its habitat improvements. A redd is an area in which a female trout deposits eggs for fertilization by a male trout. Colyer said redd numbers in one key tributary, Sheep Creek, have risen dramatically since a restoration project was implemented there in 2014.
“It shows the fish are getting into good spawning habitat,” Colyer said.
Colyer said the tributaries also have deeper pools and much more shade from new willow trees. The researchers will be collecting temperature data throughout the summer from probes set up within the watershed.
Colyer explained the watershed is important because it involves a unique population of cutthroat trout that grow large in the reservoir and use rivers and creeks to spawn. “It’s a migratory behavior a lot of native trout populations have lost,” Colyer said.
Improving the Blackfoot River Wildlife Management Area Last year, UBC cut 500 conifers from within aspen stands in the Blackfoot River Wildlife Management Area.
The group placed the trees throughout the river to provide fish cover, stabilize banks, deepen pools and filter sediment. Jason Beck, a regional wildlife habitat biologist with the Idaho Department of Fish and Game and supervisor of the WMA, said another 700 conifers are set to be removed from aspen groves and placed within the river this year. They also plan to plant thousands of willows.
“I think it’s working pretty well,” Beck said. “We have more deep water and more vegetation than we normally would have this time of year even during an average year.” Another effective UBC program has been a grazing exchange with Bear Lake Grazing Co. Beck explained that about 1,000 head of the company’s cattle that normally graze along important Bear River spawning tributaries are moved each spring to graze within the upland meadows at the WMA.
The practice keeps the cattle out of the tributaries at a time when trout are laying their eggs, thereby protecting the eggs from trampling and excessive sediment.
The newest UBC member, Itafos, has operated the Conda fertilizer plant in Soda Springs since 2018, when Agrium had to divest itself of the facility under the terms of a merger. Jon Goode, manager of special projects with Itafos, said his company has been committed to protecting the environment since its inception and joining UBC represented a “natural next step from what we had already been doing.”
“They’ve done great work. It’s a unique collaboration of different folks,” Goode said. “Some of the projects in the Upper Blackfoot they’re seeing the results. They’re seeing fish where they hadn’t seen fish in a long time. To me that’s a great success.”
This article originally appeared on the Idaho State Journal
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