By John Bulger jbulger@journalnet.com BEAR LAKE — The three Idaho Fish and Game biologists wade slowly through the frothing creek that spills into Bear Lake, two carrying nets while the lead man sweeps a wand slowly through the water. One netter surges towards movement in the water and deftly captures a huge trout that has been stunned by electroshock.
Over the next 15 minutes, the team nets numerous other vividly colored trout—some weighing more than 10 pounds—that are schooling in a pool on Fish Haven Creek, unable to further ascend the stream to spawn because of the velocity of the water funneling through a highway culvert.
Bonneville Cutthroats were once so prevalent that they were considered nuisance fish. By the 1950s, the species, closely related to the Yellowstone Cutthroat, was believed to be extinct as a pure population due to overharvest, competition by non-native species, hybridization and habitat loss.
However, studies in the 1970s compared the trout with museum specimens from the turn of the century and found them genetically identical. A program to maintain and increase the Bonneville population began.
Fish Haven Creek is a historical spawning tributary for Bear Lake Bonneville Cutthroat, but agricultural and urban development have essentially negated any natural reproduction there, as it has in many other tributaries. Through the collaborative efforts of private citizens, state agencies and conservation groups, it is hoped the fish will again find their riparian road to romance unobstructed.
About five miles south on the lake’s shore, in Garden City, Utah, the Utah Division of Wildlife Resources has operated its fish trap on Swan Creek for the past 30 years. On this early June day, the creek is running gin clear, even though a torrential rainstorm passed through the area the night before. Like Fish Haven, this is a historical tributary for spawning Bonneville Cutthroat. Unlike the former, Swan Creek offers no barriers for the trout to move upstream.
“Swan Creek is the only pure connected tributary in the system,” said Trout Unlimited Fisheries Biologist Kirk Dahle.
A small, mossy-roofed building over the creek houses a group of UDWR employees and volunteers who are busy tagging and weighing the trout which have been trapped in the structure on their spawning run.
Bear Lake Fisheries Biologist Scott Tolentino and his staff grab the female trout—hens, in biology vernacular—with practiced ease and gently “milk” a portion of the eggs from them after subjecting them to a brief anesthetic bath. The milt, or sperm, is similarly coaxed from the males, known as bucks. The milt and roe from five males and five females are combined after undergoing a quick iodine bath to remove any possible sources of contamination.
“The fertilization takes place almost immediately,” Tolentino said.
The resulting fry are raised at a state hatchery and then released back into the system after one year.
The fish which have been milked are released above the trap to spawn naturally. It is hoped that fish will have more options than Swan Creek for natural reproduction in the near future.
“What we’re looking to do is reconnect these migratory habitats,” said Dahle. “Our efforts now are to get some natural spawning in the tributaries.”
David and Claudia Cottle’s home on the west shore of Bear Lake abuts Fish Haven Creek. It also borders the highway, which is a major impediment for trout, due to the narrow culvert which crosses under it. The Cottles are co-executive directors of Bear Lake Watch, a group which attempts to bring all parties to the table to discuss and identify common goals to help maintain and improve the Bear Lake ecosystem. Given their interests in preservation and having the creek in the side yard, rehabilitating the tributary for the trout was an easy decision.
“He basically instigated the whole thing,” said Warren Colyer, who directs the Bear River native trout program for Trout Unlimited.
Cottle asked Trout Unlimited to meet with the Fish Haven Irrigation Company to see what could be done. The involvement of the irrigators was a key component. Irrigation diversions funnel water down man-made canals. Unfortunately, they can also funnel trout. Once the water flow is shut down in the fall, the fish in the canals die.
The diversions can also present an insurmountable obstacle for fish as they make their way upstream. Finally, in low water years, most of the creek’s flow may be shunted from the main channel into the canals.
On this sunny morning, several miles up Fish Haven Creek, Cottle, Colyer, Dahle, David Stock from the irrigation company and David Pacioretty of the Bureau of Land Management show off one of the signature pieces of their collaborative efforts. At the head of the irrigation diversion is a newly installed fish screen of which the group is justifiably proud.
The apparatus is a flat plate fish screen, also known as a non-mechanical fish exclusion device. As the head gate is opened and the water begins to course through the 30-foot long trough, a low hum fills the air. The harmonic resonance is part of the screen’s design, a vibration which serves to move gravel through the screen.
“These things are a dream,” Dahle said. “You turn it on, you forget about it.”
The screen portion looks sort of like a cheese grater. At the top of the gate, it spans the whole width, but narrows down the length of the trough. A portion of water strains through the screen during the run while the sticks, leaves and gravel and other foreign matter float and bounce through and are redeposited in the main tributary. Fish moving back into the lake also make it back into the tributary, rather than going into the canal. The screening benefits downstream irrigators by keeping material out of their water supply.
The design is simple but elegant. Where some fish screens will clog with debris, cutting off flow into the canal, the flat plate screen sweeps and vibrates itself clean. “Other screens will clog in about 15 or 20 minutes,” Dahle said.
Further downstream, another screen device has been put in place, involving a rotary drum screen, a porous cylinder which slowly rotates in the water flow, turned by a paddle wheel. This type of screen is common, with hundreds having been successfully deployed in Idaho.
Fish Haven Creek now sports five new fish screens. A portion of the funding has come from “The Reserve,” a 750-acre upscale housing development. The developers have also agreed to trade surface water rights for ground water rights, ensuring adequate flows in the creek. Other contributors include Bear Lake Watch, TU, the Idaho Dept. of Fish and Game, BLM and the U.S. Forest Service. Those funds have been matched by the U.S. Fish and Wildlife Service. All told, the screens to keep the fish safe have cost about $500,000.
The means for the fish to move up the stream has yet to be remedied.
Colyer explains that it was important to fix the upstream problems, keeping the fish out of the canals, before dealing with the barrier the highway creates for the fish to swim upstream.
“Now that they’re all screened, we can fix that barrier,” he said. “The vision for this stream is to restore it to migratory lake spawning.”
Dahle and Colyer estimate costs as high as $1 million for the next phase of work on Fish Haven, a new culvert which will allow the fish to pass under the highway. The coalition of groups is working on funding sources for the redesign of the culvert.
Down below the highway, a quarter-mile from the lake, the fish that were electroshocked are thrashing about in a large tub of water. Dahle dips his arms into the tub and seizes a monster male trout, its gender evident by its vivid spawn colors. Grabbing the trout by the tail and supporting it with his other hand behind the gills, he admires the fish like an envious angler, although he’s done this many times. He places the trout in smaller tub that has an anesthetic in the water which calms the fish. He then measures the trout—29 inches in length. The data is recorded by another worker.
“I’d estimate that fish is about 13 pounds” Dahle said.
This fish, which is likely at least five years old, has spawned naturally. That fact that it is wild is evident, as the fish still has a full adipose fin. Hatchery fish have the small, vestigial fin on the back clipped to help identify them.
The fish is tagged with a small plastic widget near its dorsal fin. Dahle then makes a small incision in the fish’s underside and inserts a small glass capsule into the body cavity. This passive integrated transponder contains an electromagnetic coil and a microchip. The PIT is inert until an inductive pulse is sent by a reader or an antennae, which provides a brief charge to relay a radio message containing small bits of identifying data.
Several of the fish in the tub already have PIT tags, as can quickly be ascertained by the hand-held reader. An antennae has been installed on the upstream side of the highway culvert, able to detect any fish that have been able to surmount the high-speed flow and break through upstream.
A few fish have made it through the bottleneck. Most do not. Some of the fish netted today have tail fins that are tattered, likely indicating numerous unsuccessful attempts to make it through the culvert’s maelstrom. Dahle dips his hands into the holding tub again and hefts another rose-and-orange-hued behemoth that appears unmarked.
“Beautiful fish,” Dahle said. “It’s not beat up, so it probably came up in the last day.”
Once a fish is tagged and measured and the data collected, it is handed over to a young man who stands in the creek, holding the trout in the restoring flow until the numbing effects of the anesthetic wear off.
The fish moves lightly between the biologist’s supporting hands. Suddenly, with a flick of the tail, the fish is gone. Within a few minutes, it is gently feeding on surface insects just a short way downstream, seemingly oblivious to the recent indignity.
The fish will eventually move on to find another tributary if it cannot muscle its way past the creek’s obstacles.
But one day— perhaps during next year’s spawn—this fish will be able to follow the route of its ancestors.