TWIN FALLS — A bubble-gum pink substance rests on a branch. It’s completely foreign to the 10-mile stretch of river surveyed July 24 during an annual survey.

These alien-like pink bubbles are apple snail eggs. Apple snails are mollusks from South America introduced through aquaculture trade. The eggs are unpalatable to predators, which can lead to an overabundance of the species.

“Hopefully the winter will kill anything that’s here,” Aaron Ursenbach said. “They adapt quickly though.”

“Gosh dang it, Darwinism,” Jason Parker joked.

The apple snails were just one of the many invasive species and noxious weeds found during the yearly survey of the river.

Invasive species are classified as animals or plants that are not native to an area. The invasive species outgrow and out-compete native species and dominate an ecosystem because these new species don’t have a natural predator.

Ursenbach and Parker were part of the team that surveyed the 10-mile stretch of river to inspect what noxious weeds were prevalent.

Idaho has 67 noxious weed species; 16 of these are aquatic plants. These plants often thrive in warmer waters and have the potential to damage. Aquatic noxious weeds can build up and stop the flow of streams and damage pipes, which can cost millions of dollars.

“We’re very hydro-dependent,” Ursenbach said. “It affects everything we do.”

During the survey, Hydrilla verticillata was repeatedly found. Ursenbach and his invasive species team go through streams every week and pull out Hydrilla verticillata.

During their inspection of a small stream in Twin Falls on July 26, several noxious weeds and invasive species were found.

The plant requires minimal sunlight, so it can survive in pipes and under other plants. Hydrilla verticillata was introduced to Idaho as an aquarium plant and is extremely aggressive. It’s considered to be the most problematic aquatic plant in the country.

People dumping home aquariums into local bodies of water is a growing problem, Parker said. Pet owners think it’s a more humane option but the repercussions on the local ecosystem are massive.

Idaho law says the duty and responsibility fall on landowners to control noxious weeds on their property.

Jeremy Varley, the Idaho Department of Agriculture section manager for noxious weeds, said that the best resource for landowners who don’t know what to do with noxious weeds growing on their property is to contact their county weed superintendent to point them in the right direction.

“It’s up to landowners, the counties and the state; we’re a team trying to protect Idaho,” Ursenbach said. “The first thing that people can do to help is to educate themselves on the subject.”

A large threat to ecosystems is quagga and zebra mussels. These mussels clog water pipes and other infrastructure. They eat plankton in the water which threatens the entire ecosystem.

If mussels were to get into the Idaho water system, it could be devastating to agriculture, Twin Falls County Weed Superintendent Kali Sherrill said.

Idaho has been trying to keep quagga and zebra mussels out of lakes and reservoirs since 2008. One of the biggest efforts is to prevent invasive mussels from getting into the Columbia Basin.

Nicholas Zurfluh, the Idaho Department of Agriculture section manager for invasive species, said Idaho is one of the last states free of invasive quagga and zebra mussels. He said Oregon, Washington, Wyoming and Idaho are some of the last places that have not had mussels invade the water system.

“This speaks to the opportunity that we have here,” Zurfluh said. “To keep the Columbia Basin clean is a huge opportunity for us.”

So far, during the 2018 boating season, 66,678 boats have been checked and 43 have been mussel-fouled boats. More than 500,000 boat inspections have been conducted in Idaho since 2009, and 218 were found carrying quagga or zebra mussels. Watercraft that are considered “high-risk” to the state of Idaho are boats that have been in mussel-infested states within the past 30 days, show dirt or grime below the waterline or boats that have standing water on board.

The first and most effective step is prevention. Prevention starts with inspecting your boat when it leaves the water, using the clean, drain, dry system. Kurfluh said this system should become a habit for anyone who goes boating. Anything that goes in the water is required for a mandatory inspection at one of the inspection stations.

“People come from all over to enjoy our water,” Sherrill said. “People should be happy with keeping our water clean.”

For more information, visit invasivespecies.idaho.gov or contact the Twin Falls County Noxious Weed Bureau at 208-734-9000 or email weeds@co.twin-falls.id.us

AMERICAN FALLS — The Snake River’s banks were littered with several species of dead trophy fish when David Raisch floated the reach below American Falls Dam throughout Saturday.

“I observed multiple sturgeon that were just gasping for air, including some that were 5 feet long,” said Raisch, who works as a fly fishing guide with Palisades Creek Lodge.

Sources with the Idaho Department of Fish and Game say hundreds of trout, small-mouth bass and yellow perch and at least 10 sturgeon were victims of a fish-kill spanning from the dam to the Vista boat ramp and Pipeline area. It was apparently triggered when dissolved oxygen levels plummeted from late Thursday to early Friday.

Fish and Game officials anticipate delayed mortality may continue throughout the next few days.

The cause of the oxygen drop remains under investigation, but sources with the Idaho Department of Environmental Quality have a theory, which is supported by Fish and Game biologists. Lynn Van Every, DEQ’s regional water quality manager, said a prolonged period of hot and calm weather likely resulted in a layer of warm water trapping colder water devoid of dissolved oxygen. Strong winds within the reservoir likely blew the warm water layer upstream from the dam, allowing only the cold water to enter the dam’s penstocks — large pipes that feed Idaho Power turbines.

The cold-water surge lowered oxygen levels below the dam to the point that fish began to die. Van Every confirmed Idaho Power met the conditions of its permits to operate the dam and won’t be fined.

“It happened in relatively short order,” Van Every said. “It’s not uncommon to have low dissolved oxygen coming through, but it sort of happened in a hurry.”

Raisch fished the same reach on Friday night. Though he considered it odd that he had no bites, he didn’t notice the fish-kill until the following morning. He contacted Fish and Game to report the fish-kill after his Saturday float, also describing how surviving trout and smallmouth bass acted “as if they’d had a stroke.”

“It’s a heart-breaker,” Raisch said. “It takes a long time to build those good resources and trophy fishing.”

Dave Teuscher, regional fisheries manager with Idaho Fish and Game, said sensors within the dam and 150 yards downstream constantly monitor dissolved oxygen content, which is considered healthy for fish at levels of above 5 milligrams per liter. Teuscher explained the sensors detected levels dropping from 5 milligrams per liter to zero from 10 p.m. Thursday to midnight Friday. The sensors automatically triggered a blower to activate and oxygenate water flowing from the first penstock. A second blower activated when dissolved oxygen levels hadn’t sufficiently recovered a few minutes later. Ultimately, an alarm signaled Idaho Power staff to respond and open a spillway to add more oxygen.

“Everything Idaho Power has in their water-quality requirements occurred, and that was helpful because this thing could have really turned into a larger fish-kill if that hadn’t happened,” Teuscher said.

DEQ responded to the scene on Sunday, and a Fish and Game crew conducted analysis on Monday morning. On Tuesday afternoon, Fish and Game staff manned a boat, scouring for dead sturgeon to gather biological data, such as growth rate and age.

Some of the sturgeon that were killed were in excess of 30 years old, Teuscher said. The department started stocking them in the reach in the 1980s for catch-and-release fishing and has been stocking the river upstream from American Falls to Idaho Falls more recently.

Idaho’s sturgeon are considered a species of greatest conservation need.

Though Idaho Power was in compliance with its license and obligations to operate the hydro-power turbines, Brad Bowlin said the company will, nonetheless, partner with DEQ and Fish and Game to analyze weather data, incoming flows, oxygen levels and other factors to determine “if there’s something we need to do to our operations.”

Bowlin said Idaho Power hopes to discover what conditions were different during that four-hour period that could aid in forecasting to avoid future problems.

“That was the big issue, that this happened in such a short period of time,” Bowlin said.

Larry Larsen, owner of Snake River Fly Shop in Pocatello, said the Snake River below American Falls is blue-ribbon water utilized by countless anglers and key to his business’s success. In late July, he said the reach was fishing better than during any period in the past five years. But Larsen is also glad the damage wasn’t greater and is already hearing reports that the fishery is recovering.

“I had a customer come in who was fishing there this morning, and he was catching fish,” Larsen said.

AMERICAN FALLS — The Snake River’s banks were littered with several species of dead trophy fish when David Raisch floated the reach below American Falls Dam throughout Saturday.

“I observed multiple sturgeon that were just gasping for air, including some that were 5 feet long,” said Raisch, who works as a fly fishing guide with Palisades Creek Lodge.

Sources with the Idaho Department of Fish and Game say hundreds of trout, small-mouth bass and yellow perch and at least 10 sturgeon were victims of a fish-kill spanning from the dam to the Vista boat ramp and Pipeline area. It was apparently triggered when dissolved oxygen levels plummeted from late Thursday to early Friday.

Fish and Game officials anticipate delayed mortality may continue throughout the next few days.

The cause of the oxygen drop remains under investigation, but sources with the Idaho Department of Environmental Quality have a theory, which is supported by Fish and Game biologists. Lynn Van Every, DEQ’s regional water quality manager, said a prolonged period of hot and calm weather likely resulted in a layer of warm water trapping colder water devoid of dissolved oxygen. Strong winds within the reservoir likely blew the warm water layer upstream from the dam, allowing only the cold water to enter the dam’s penstocks — large pipes that feed Idaho Power turbines.

The cold-water surge lowered oxygen levels below the dam to the point that fish began to die. Van Every confirmed Idaho Power met the conditions of its permits to operate the dam and won’t be fined.

“It happened in relatively short order,” Van Every said. “It’s not uncommon to have low dissolved oxygen coming through, but it sort of happened in a hurry.”

Raisch fished the same reach on Friday night. Though he considered it odd that he had no bites, he didn’t notice the fish-kill until the following morning. He contacted Fish and Game to report the fish-kill after his Saturday float, also describing how surviving trout and smallmouth bass acted “as if they’d had a stroke.”

“It’s a heart-breaker,” Raisch said. “It takes a long time to build those good resources and trophy fishing.”

Dave Teuscher, regional fisheries manager with Idaho Fish and Game, said sensors within the dam and 150 yards downstream constantly monitor dissolved oxygen content, which is considered healthy for fish at levels of above 5 milligrams per liter. Teuscher explained the sensors detected levels dropping from 5 milligrams per liter to zero from 10 p.m. Thursday to midnight Friday. The sensors automatically triggered a blower to activate and oxygenate water flowing from the first penstock. A second blower activated when dissolved oxygen levels hadn’t sufficiently recovered a few minutes later. Ultimately, an alarm signaled Idaho Power staff to respond and open a spillway to add more oxygen.

“Everything Idaho Power has in their water-quality requirements occurred, and that was helpful because this thing could have really turned into a larger fish-kill if that hadn’t happened,” Teuscher said.

DEQ responded to the scene on Sunday, and a Fish and Game crew conducted analysis on Monday morning. On Tuesday afternoon, Fish and Game staff manned a boat, scouring for dead sturgeon to gather biological data, such as growth rate and age.

Some of the sturgeon that were killed were in excess of 30 years old, Teuscher said. The department started stocking them in the reach in the 1980s for catch-and-release fishing and has been stocking the river upstream from American Falls to Idaho Falls more recently.

Idaho’s sturgeon are considered a species of greatest conservation need.

Though Idaho Power was in compliance with its license and obligations to operate the hydro-power turbines, Brad Bowlin said the company will, nonetheless, partner with DEQ and Fish and Game to analyze weather data, incoming flows, oxygen levels and other factors to determine “if there’s something we need to do to our operations.”

Bowlin said Idaho Power hopes to discover what conditions were different during that four-hour period that could aid in forecasting to avoid future problems.

“That was the big issue, that this happened in such a short period of time,” Bowlin said.

Larry Larsen, owner of Snake River Fly Shop in Pocatello, said the Snake River below American Falls is blue-ribbon water utilized by countless anglers and key to his business’s success. In late July, he said the reach was fishing better than during any period in the past five years. But Larsen is also glad the damage wasn’t greater and is already hearing reports that the fishery is recovering.

“I had a customer come in who was fishing there this morning, and he was catching fish,” Larsen said.

Unsafe shooting is a major cause of wildfires in the Gem State, and with the advent of explosive rifle targets, the problem has gotten worse. At least five recent wildfires in the region have been caused by people setting off explosive targets in dry grass- and sagebrush-filled areas.

Vehicles spark more wildfires than any other human-related cause in Idaho, often when hot exhaust systems come into contact with dry grasses or when dragging chains shower sparks on them. But shooting causes the second-most, more than people throwing lit cigarette butts out of vehicles.

“Since 2015, about 30 percent of wildfires were caused by shooting,” said Melissa Yunas, public information for the Bureau of Land Management’s Fire Prevention and Education Team.

So far this year, at least 10 wildfires in Idaho have been caused by unsafe shooting, and another five are suspected to have been caused in a similar way. In addition to exploding targets, steel-core rounds, which can cause sparks, as well as incendiary or tracer ammunition can cause fires.

Shooting appliances also can cause sparks, and sometimes a hot bullet landing in dry grass is enough to spark a blaze.

Such blazes include the 64,000-acre Sharps Fire in Blaine County which has forced many evacuations and is only 57 percent contained. Yunas said an individual has confessed to causing the fire with an explosive target, but a decision hasn’t yet been made whether to prosecute him.

High-explosive targets have been on the market for about two decades. Among the best known is a variety called Tannerite. It’s a so-called “binary explosive” consisting of two mixtures that are combined to make the explosive. Among other ingredients, the Tannerite contain ammonium nitrate, a component of the explosives used in the 1995 Oklahoma City Bombing. A similar compound was used in a series of bombings in New York and New Jersey in 2016 that left 31 people injured.

Since coming on the market, the targets have been involved in numerous cases of unsafe, even deadly, behavior outside of causing wildfires. An Oklahoma man was charged with manslaughter after he filled an outdoor stove with two pounds of the substance, and a flying piece of shrapnel killed an 8-year-old boy. He later pleaded guilty.

Numerous other charges have resulted from its use, as when a Minnesota man gathered 100 pounds of the substance, loaded it in the back of a dump truck and set it off, obliterating the truck. He was on probation at the time.

Yunas noted that explosive targets as well as incendiary, steel-core and tracer rounds are banned for possession or use on BLM lands between May 10 and Oct. 20. Even when shooting non-banned rounds at regular targets, precautions should be taken to avoid sparking a wildfire, Yunas said.

These include clearing vegetation near to targets, and ensuring that the area behind the target doesn’t present a danger of wildfire.

“Be aware of your location,” she said. “Make sure there are no fire restrictions in effect.”

Avoid shooting on days with low relative humidity, high winds or red flag warnings, she added.

“Just like any activity, whether you’re welding outside or you have a campfire, you should bring water and a fire extinguisher and a shovel. Bring a cellphone, and if a fire starts call 911 immediately,” Yunas said. “We just want people to be careful. We’re not discouraging people from shooting; you just have to use caution.”

A giant grizzly that state wildlife managers euthanized in the Meeteetse, Wyoming, area in early April is destined for a second life in education.

The boar was the biggest bear most experts had ever seen in the Yellowstone ecosystem, said Dusty Lasseter, large carnivore biologist for the Wyoming Game and Fish Department. Even after having just finished hibernating, the bear was well over 600 pounds. A grizzly will typically lose more than 25 percent of its weight during hibernation — meaning it would have gained at least another 150 pounds by fall.

“There are no records of (a grizzly) this big caught around here,” Lasseter said.

Had the bear lived through the summer, it likely would have been close to an 800-pound bear in the fall. Lasseter trapped the bear after repeated conflicts with livestock. It was a bad day at work, ending with the euthanization of a very special bear, Lasseter said.

“It’s one of the harder things we have to do,” Lasseter said. “We always want to see these animals on the landscape.”

The Game and Fish Department wanted to do something special to honor the giant and donated the bear to Meeteetse Museums. In 2000, a boar known as Little Wahb was donated to the Meeteetse Museum, part of a three-museum collaboration in the historic town. Little Wahb was big. Stories exaggerating its size grew even bigger. The Billings Gazette reported Little Wahb to be a 900-pounder that year. Despite its reputation, it’s no Big Joe, Lasseter said.

“Side by side, Big Joe will make Little Wahb look small,” Lasseter said.

Little Wahb, similarly euthanized for cattle depredation, is currently on display at the museum. Soon it will be easy to compare the size of the two bears; Big Joe is going to be stuffed as a full-body mount and used in a special educational display at the museum.

Big Joe, nicknamed for Meeteetse-area rancher Joe Thomas, had been relocated previously after conflicts.

Thomas has been seeing more bears on his property over the last decade, despite living just outside of Meeteetse.

“They move them, but they keep coming back,” Thomas said. “I always get a bear or two or three.”

Thomas has seen some depredation of his cattle but has mostly learned to live with the large carnivores. The last time a bear was trapped and removed from his property was about eight years ago, he said. The bear was about 25 years old and weighed over 500 pounds.

Thomas first saw Big Joe on April 4, just days after the bruin came out of hibernation. Thomas had also seen sows with their cubs on the expansive cattle ranch.

“More sows and cubs keep showing up here,” Thomas said.

After the boar was euthanized, Thomas photographed the bear, amazed by its size. He’s happy the bear will be used in an educational display, but he’s not so kicked up about the name chosen.

“That’s the name they picked. It’s no big deal to me,” Thomas said.

The display will feature modern technology to highlight drone footage taken by Thomas, DNA testing results, the history of the bear’s life and other aspects of grizzly education, said David Cunningham, director of the museums.

Meeteetse Museums are not alone in their attempt to create an interactive experience through technology. Museums, including the Draper Natural History Museum’s new golden eagle installation, are embracing tools from chatbots (computer programs which conduct a conversation via auditory or textual methods) to digital projections.

Some museums are even working to save you the trip. The Smithsonian American Art Museum, in Washington, D.C., is using virtual reality to bring its collections to patrons online.

Cunningham is more interested in getting visitors to come to Meeteetse. It’s hoped the new display will help drive traffic — especially during the offseason when Yellowstone National Park is closed, he said.

With some help, the museum will have a grand opening for the display within the next year. But first they need to find some donors.

“It will take a long time to raise the money to construct the educational display,” Cunningham said.

The price is still a mystery, but will run many thousands of dollars, depending on how much technology is used and the price of the full-body taxidermy by Nature’s Design, in Cody.

The first and most effective step is prevention. Prevention starts with inspecting your boat when it leaves the water, using the clean, drain, dry system. Kurfluh said this system should become a habit for anyone who goes boating. Anything that goes in the water is required for a mandatory inspection at one of the inspection stations.

Because of the current fire risk condition throughout Idaho, the Idaho Department of Fish and Game (IDFG) is imposing a Stage I Fire Restriction on IDFG-owned and managed lands statewide, effective immediately.

Until further notice, the following restriction applies to all Wildlife Management Areas and fishing access areas owned or managed by IDFG.

Stage I Fire Restrictions

Building, maintaining, attending, or using a fire, campfire, or stove fire except within a designated recreation site, within a fire structure provided by the administrative agency, or on their own land and only within an owner-provided fire structure (see definition below)

Smoking, except within an enclosed vehicle or building, a developed recreation site, or while stopped in an area at least three feet in diameter that is barren or cleared of all flammable materials.

Exemptions

Persons with a written permit that specifically authorizes the otherwise prohibited act.

Persons using fire fueled solely by liquid petroleum or LPG fuels.

Persons conducting activities in those designated areas where the activity is specifically authorized by written posted notice.

Any Federal, State, or local officer, or member of an organized rescue or firefighting force in the performance of an official duty.

All land within a city boundary is exempted.

Other exemptions unique to each agency.

The wildlife management areas covered by this announcement include: Tex Creek, Sand Creek, Mud Lake, Market Lake, Deer Parks, Cartier Slough, Sterling, Portneuf, Blackfoot, Georgetown, Montpelier, Hagerman, Niagara Springs, CJ Strike, Camas Prairie Centennial, Billingsley Creek, Big Cottonwood, Carey Lake, Cecil D. Andrus, Payette, Montour, Boise River, Fort Boise, Craig Mountain, Red River, Boundary Creek, McArthur Lake, Pend Oreille, Farragut, Coeur d’Alene, Snow Peak. Signs are being posted at many of these areas, but the restrictions are in effect whether or not signs are present.

According to Upper Snake Regional Habitat Manager Rob Cavallaro, “Dry conditions around the State have made the potential for wildfires extremely high. As a result, IDFG has implemented a restriction on all open fires on IDFG- managed lands and access sites in the Upper Snake, Southeast, Southwest, Magic Valley, Clearwater, Panhandle, and Salmon regions. The use of exploding targets and fireworks are always prohibited on IDFG owned lands.”

IDFG is also asking visitors to these lands to be cautious of the potential for fires caused by other sources as well.

Fire restrictions will remain in place until fire conditions change and the public will be notified at that time. Anyone with questions should contact:

Upper Snake Regional Office at 208-525-7290

Southeast Regional Office at 208-232-4703

Southwest Regional Office at 208-465-8465

Magic Valley Regional Office at 208-324-4359

Panhandle Regional Office at 208-769-1414

Clearwater Regional Office at 208-799-5010

Salmon Regional Office at 208-756-2271

I’ve been super busy lately and have a new project coming up which will require more traveling and busyness. So what’s a guy to do? Take off on a backpacking (BP) trip for a few days of course! My youngest daughter normally goes with me but was tied up so I went by myself.

I had a lot of articles to get in so I whipped out and then put together all my BP gear that had been put away for the winter. Gee that takes a while due to all of the little gizmos that BP requires. I want to write a BACKPACKING 101 article soon so right now I won’t go into all of the gear you’ll want to have.

It’s a drive up to the trailhead and then of course a bit of a hike in to the spot I wanted to camp at. I wanted to leave early enough to get in and set up camp and still have a few hours to fish before dark so I could hit the evening hatch. I arrive at the trailhead and there were only 4 to 5 trucks. Hopefully they’d scattered in different directions than I was going.

I got to my spot and hadn’t seen a soul. Good. I slapped up camp, gathered a little wood and then rigged up my flyrod and trotted down the trail to the first hole. I used to BP into this spot the week after the 4th. Any earlier and you’d hit too much snow. But the last 14 to 15 years, I’ve pushed it back to the middle of August and on into September because the runoff has slowed down and the fish are more congregated in the holes. Plus, the big bull trout have come upstream by then.

Oh no! I arrived at the first good hole and there was a massive log jam in it. Logs had pretty much jammed up the whole hole. It was unfishable. About 5 years ago on a trip with Kolby there had been a huge snowslide that pushed a ton of dead trees into the river a few miles upstream. I guess they had finally made it down to this hole. Or maybe there’d been a new slide, although I hadn’t seen it while hiking in.

We’ve got to stop and ponder something a minute. Remember the Jarbridge Shovel Brigade in Nevada? If you remember, the overreaching feds refused to let them repair a road because a few piles of dirt may fall in the river and hurt the bull trout. When they refuse to fight forest fires, which results in miles of burned and dead standing timber that will all get pushed down into the rivers and result in huge mudslides for years to follow, does that not hurt more bull trout than re-building a road?

Some of these log jams are so packed that there is no way that a 30-inch bull trout can pass through them to go upstream and spawn. And one year there was a big mudslide that muddied up the river for miles downstream. The river looked like pig slop. Focus on the real problems boys.

So the hole where the big 30-inch bulls like to gather in is gone for this year and maybe a few more to come. It’s a mess.

I doodled around until dark and then hiked back to camp and built a fire and relaxed. The next morning I woke up, dipped a pot of crystal clear water out of the river and heated it up. Ahh, there’s nothing like breakfast in the high country. I ate a couple of packs of flavored oatmeal, slammed down a few cups of coffee and hit the trail.

But before we get into the day’s happenings I have to mention. I’d caught two mice over the night. I always carry two mouse traps and put them under my hanging pack. I hate for them to get into my food.

OK, enough of being a drama queen. I headed downstream hitting the holes. Whoa, something was wrong. I was not catching very many fish and nothing very big. I started off using some big black bead head wooly boogers. The last few years I’ve been using some flies called Fish Skulls that I order from flydealflies.com.

Later in the day I switched to dry flies. I caught enough to keep it interesting but not like norm. I found a few huckleberries that I stored in a water bottle to put in my oatmeal the next day. I fished until dark and then drug back into camp and built a fire and heated up a Mountain House Beef Stroganoff dinner. That’s my favorite from MH.

The next morning I put huckleberries in my oatmeal, wolfed that down and then took off fishing again. Today I netted a few nice native cutthroats, one was pushing 15-inches and a 15-inch whitefish.

Later that afternoon I found a good patch of huckleberries and spent over an hour picking them. I got enough to take some home for Katy & Kolby. Well, the trip soon cam to an end and I hit the hot dusty trail back to the trailhead. Uggh, I must be out of shape. The hike out about killed me.

Tom Claycomb lives in Idaho and has outdoors columns in newspapers in Alaska, Idaho, Utah, Nevada, Colorado and Louisiana. He also writes for various outdoors magazines and teaches outdoors seminars at stores like Cabela’s, Sportsman’s Warehouse and Bass Pro Shop.

BOISE, Idaho (AP) — The federal government on Wednesday put on hold one of the largest-ever projects to remove juniper trees to help an imperiled species after an appeal by an environmental group seeking to halt the plan.

A U.S. Department of the Interior administrative panel granted the U.S. Bureau of Land Management’s motion to set aside its decision in May to remove juniper trees from about 1,100 square miles in Idaho’s Owyhee County.

The Bureau of Land Management in initially approving the project said it would protect habitat for imperiled sage grouse and benefit cattle ranchers.

Western Watersheds Project in June filed its appeal with the Interior Board of Land Appeals, an appellate review panel that issues final decisions for the Interior Department. Following the appeal, the BLM then asked the review panel to put on hold its May decision, saying Western Watersheds Project “raised issues in its appeal that the BLM wishes to consider further and address in a revised decision.”

The review panel’s order on Wednesday granted the BLM’s request.

“Today’s decision is a win for sage-grouse and all other species that depend on Idaho’s unique and imperiled sagebrush ecosystem,” Scott Lake, Idaho director for the Western Watersheds Project, said in a statement. BLM “didn’t weigh the limited benefits of this project against the significant environmental costs.”

Experts say warmer winters combined with fewer wildfires at higher elevations of sagebrush steppe have allowed junipers to expand into areas once filled with sagebrush and native grasses. Sage grouse survival is completely dependent on sagebrush.

Western Watersheds Project contends that studies show western juniper, a native species, has expanded and retreated several times over thousands of years, and the BLM’s plan to cut them down is being driven by grazing interests, not concerns about sage grouse.

The group contends that cattle grazing disturbs the soil and allows invasive species, particularly cheatgrass, to take root. Fire-prone cheatgrass is often the primary fuel in giant rangeland fires in the U.S. West that destroy sagebrush habitat needed by sage grouse.

Venetia Gempler, a BLM spokeswoman, said the agency didn’t immediately have a comment on the review panel’s decision.

It’s not clear when the BLM might issue a revised decision on the juniper-cutting plan, called the Bruneau-Owyhee Sage-Grouse Habitat Project. The BLM has removed or has plans to remove junipers in other states as well.

The ground-dwelling, chicken-sized sage grouse are found in 11 Western states. The males are known for performing an elaborate mating ritual that includes making balloon-like sounds with two air sacks on their necks.

Between 200,000 and 500,000 sage grouse remain, down from a peak population of about 16 million. Officials in 2015 opted not to list the birds as needing federal protections under the Endangered Species Act and instead imposed land-use restrictions leading to multiple lawsuits from industry and environmentalists. Federal officials are expected to review the decision in 2020.