For a start, you can blame the enthusiasm of "bucket biologists" in the West. As far back as the 1800s, these avid anglers and fishery managers took it upon themselves to bring fish -- and fishing -- to lakes and streams in the high country and backcountry of America. A lot of people praised them for their efforts.
But now we know something about the consequences of rashly interfering with the ecology of remote areas. Of the roughly 16,000 alpine lakes that dot our Western mountains, more than 95 percent were once naturally fishless, though they weren't the "barren" places they've often been labeled. Instead, they teemed with a rich diversity of aquatic life that evolved without the presence of an effective predator such as trout.
Native trout populations, which mostly inhabited rivers and streams, were also harmed by introduced fishes that brought disease, competition and hybridization. Yet despite irrefutable scientific evidence of the ecological damage from fish stocking, the practice continues in America's most revered wilderness areas.
At the same time, fishery managers and many private organizations are working to recover populations of native trout. It's a great idea and long past due. But all too often these projects repeat the mistakes of the past. They benefit a single species -- cutthroat trout -- at the expense of the ecosystem as a whole. Because insects, amphibians and most other native organisms don't rise to a fly like cutthroat do, many fish managers seem blind to their existence.
The methods fish managers use to restore native trout compound the public controversy and risk to aquatic ecosystems. First, they destroy existing fish populations by dumping vast quantities of poisons such as rotenone into the waters. Rotenone, like many poisons, is a natural substance that, when applied in a high concentration, is lethal to fish and other aquatic species.
What is not entirely known is the full effect of rotenone combined with the neutralizing chemicals that are dumped in the water afterward. Nor does anyone fully understand how these deadly agents interact with the myriad other toxins that are ubiquitous in the environment. This is still under study, though a review of published research points to the potential for significant and long-term impacts to non-target aquatic communities.
But any challenge to the fish managers' tool of choice can get one dismissed as a "chemophobe" -- even when the poisoning involves one of our nation's most pristine and wild landscapes.
Consider the state of Montana's plan to poison several lakes in the legendary Bob Marshall Wilderness. The stated goal is to remove some of the non-native fish from the South Fork Flathead drainage in the hope that it will lessen the chance of these aliens commingling with the native fishes downstream. That's a goal almost anyone can support. But the devil is in the details.
To remove these fish, the state proposes to dump 15,000 gallons of rotenone poison in these wilderness lakes. And to do that, it wants to invade with helicopters, generators and motorboats, all of which are banned in designated wilderness. Then, after the poison has done its work, the state's plan calls for stocking these naturally fishless lakes with Westslope cutthroat trout. It is a species native downstream, but it's as alien to these lakes as a gorilla would be to the surrounding forest. This is fish farming masquerading as ecological restoration, made worse by the fact it is proposed for a congressionally protected wilderness.
The Wilderness Act is unique in that it represents this society's commitment to set apart some areas where we can let nature run, "an area where the earth and its community of life are untrammeled by man." The law is not so much about protecting natural museums or pristine landscapes as it is about curbing Homo sapiens' unceasing desire to manipulate nature to some "beneficial" end. As longtime Forest Service researcher Robert Lucas put it, in wilderness, "the object is to let nature "roll the dice -- and accept what results with interest and scientific curiosity." It is a check on our hubris, a statement of humility and restraint.
Restoring native species to their natural habitats is a good thing. So is protecting the native species already there. Wilderness managers in the Bob Marshall and elsewhere would do well to take a page from the work of ecologists in the Sierra Nevada, who are foregoing poisons and motorized equipment in their work to remove unwanted fish from naturally fishless lakes and thereby restore the native biota to a healthy condition.
It is tough, slow, challenging work. It respects and enhances what is unique, important and profound about wilderness.
George Nickas is a contributor to Writers on the Range, a service of High Country News (hcn.org). He is the executive director of Wilderness Watch in Missoula, Mont.