Matt Dickerson: Reflections on catching native and invasive trout
There I was again, having spent three days traveling along beautiful Wyoming trout water without a chance to actually wet my line, just as I had the previous week (and in my previous column). Only this time it was in the Shoshone National Forest and Yellowstone National Park, rather than the Bridger-Teton National Forest.
We’d visited one river where introduced trout had devastated the population of native cutthroat trout. And we’d spent a day with a U.S. Forest Service biologist visiting a river that had been chemically treated to kill invasive fish, and then replanted with a strain of cutthroat native to Wyoming — a project similar to one I wrote about in my previous column from a couple hundred miles further south. Another day was given mostly to travel across the hot flat expanses of Wyoming, and to the necessity of doing laundry after a week in the wilderness. We had lots of film footage and information from our interviews. But I had no photos of me catching trout because my flies had not even been in the water.
Finally we were settled in to a National Forest Service campground on the North Fork of the Shoshone River. It was evening. We had an early morning schedule to pack up our tents and take a drive to visit more trout water (where I couldn’t fish). But for now I had a couple hours until sunset to head out into river, just a short stone’s throw from my tent. I put my rod together, pulled on my waders, and headed out.
Julia and Yuki, my research assistants came with me, Julia with her own fly rod and Yuki with her video camera. We crossed the river on a primitive bridge and walked 50 yards upstream to a bottom of a nice looking riffle where a small stream flowed in from the north — a stream the biologist told us still had wild cutthroat trout, even though the main stem of the river was dominated by introduced rainbows. I let Julia fish the seam just below the confluence. I waded the tributary and fished on the upriver side.
Five minutes later I was releasing a fat North Fork rainbow trout, about 18 inches long, and Yuki had several minutes of footage of why many local anglers were happy to have these hard-fighting invasive trout in the river, and had no desire to see native cutthroat restored. Twenty minutes later, and 70 yards upriver, I landed and released my second one, just as big.
MATT DICKERSON HOLDS a Wyoming native Snake River fine spotted cutthroat Trout from the Bridger-Teton National Forest.
But I had spent enough time with various biologists and conservationists over the past week to know that there was a lot more at stake than the pleasure of anglers. Cutthroat had colonized these waters some 10,000 years earlier, and much of the local ecosystem was adapted to depend on this fish and its life cycle. Grizzly bears and black bears, minks and otters, bald eagles and osprey, and even pelicans depended on the cutthroat trout for a considerable amount of their protein needs. And not just animals. The nutrients get spread into the soil and feed the forests also. In Yellowstone Lake especially, grizzly bears had feasted for centuries on the hundreds of thousands of cutthroat trout running up tributary streams and downriver to spawn late spring or early summer. They did the same in the Shoshone National Forest.
But introduced trout from human stocking had devastated populations of cutthroat all across the Rockies. Lake trout through predation, brook trout primarily through competition, and rainbow trout through hybridization. And, as it turns out, one trout is not the same as the next when it comes to their place in an ecosystem. Lake trout, for example, are not available as a protein source to large birds and mammals. They spawn in the lake and not in the shallow waters of rivers and streams. Similarly, one USFS biologist, who showed us a video of a grizzly bear feasting on a spring-spawning cutthroat, said there was no documented evidence of bears eating the fall-spawning brook trout. After the introduction of lake trout, the population of osprey on the lake fell from more than 50 to fewer than five. Even the elk population began to decline, with one conjectured explanation that grizzly bears deprived of cutthroat trout turned to elk calves as their food source.
I had caught only four trout in an hour or so of fishing when a thunderstorm moved in and drove us off the river. Over the next five days, between filming and a conference, I was able to get in only one more day of fishing. But it was a good one. Tim Wade, a well-known local guide and fly-shop owner, volunteered to take a few writers out on the North Fork. Julia fished with Tim, and while Yuki filmed them she managed to elicit from him something of both his tremendous knowledge of the local water and his conservation ethic. And I took what chances I could to sneak upriver or downriver a few yards, and through the late morning managed to land seven more large rainbow trout plus two of the native species of whitefish.
The month-long excursion ended with a week-long trip into the Popo Agie Wilderness area in the southern Shoshone National Forest. A 17-mile, all-day horseback trip brought us (and our video equipment) into the South Fork of the Little Wind River where we got some great footage of a stream so overpopulated with invasive brook trout that in places it looked like the raceway of a fish hatchery. We also got some underwater footage of trout — both brook and cutthroat trout — stacked up below a waterfalls preparing to leap up it to colonize new water.
And maybe a minute or two of footage of me landing a few of those big cutthroat, when I was able to keep the brookies off my hook. When it comes to wild fish, I’m a big proponent of catch-and-release fishing. But while I crimped the barbs off most of the hooks I used, and released all the cutthroat I caught, this was one time I had no guilt about a big dinner of fresh brook trout.
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