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Feared Trout Drop-off Signals Climate Shift in Montana

October 31, 2008 at 6:40 PM EDT
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Warmer temperatures and a longer summer drought season in Montana are expected to have significant impacts on the state's trout fishing industry and ecosystem. In a special report, Heidi Cullen of Climate Central examines how climate-related changes are affecting Montana.

JIM LEHRER: And now, the first in an occasional series climate change. We begin with a report on drought and trout in Montana. Our story is produced by Climate Central, a nonpartisan scientific research group. The reporter is Heidi Cullen, a climatologist and correspondent for The Weather Channel.

HEIDI CULLEN, Climate Expert, The Weather Channel: Montana, known for its big sky and its big trout. The skies are as stunning as ever, but all is not well with Montana’s trout population.

Warmer temperatures are setting off a series of interconnected changes that are affecting Montana, but we begin with the trout. Scientists project that increasing temperatures in the coming decades could cause significant reductions in trout habitat in Montana, placing the more than $300 million fishing industry in jeopardy.

CRAIG MATHEWS, West Yellowstone, Montana: I started guiding out of West Yellowstone in 1980.

HEIDI CULLEN: Craig Mathews is a well-known fishing guide and owner of Blue Ribbon Flies in West Yellowstone.

CRAIG MATHEWS: The changes I’ve seen in the 30 years that I’ve been here, I’ve seen a lot of sedimentation in the streams. I’ve seen lower water, particularly the last 10 or 12 years.

HEIDI CULLEN: The summer drought season in Montana has grown longer.

JENNY WEST, Hamilton, Montana: This is West Fork, and we have a tailwater, which kicks out some cool water in the summer that helps with the fishery.

HEIDI CULLEN: Jenny West is a fishing guide on the Bitterroot River near Missoula. She’s been fishing the Bitterroot since she was 12 years old.

JENNY WEST: The key is July. If July is dry, then we have a pretty big drought.

HEIDI CULLEN: In addition to the long summer drought, the winter snow pack is melting earlier.

STEVE RUNNING, University of Montana, Missoula: And the big trend that we’ve identified in the last 50 years is that we’re getting a bit less snow and it’s starting to melt on the order of two or three weeks earlier.

HEIDI CULLEN: Steve Running is a professor of ecology at the University of Montana in Missoula and a member of the Intergovernmental Panel on Climate Change, which was co-recipient of the 2007 Nobel Peace Prize.

STEVE RUNNING: Trout are what we call simply a cold-water species. And so a trout literally dies at water temperatures above about 78 degrees.

It’s pretty easy to warm up water above 78 degrees if it’s just standing still. And so what keeps our water temperatures cool is that snow melt out of the mountains continuing to flow down through our rivers.

As our rivers run out of flow and you’re left with just sitting pools of water, that 78-degree threshold for trout mortality gets pretty easy to attain.

Fish essential to ecosystem

HEIDI CULLEN: Running calculates that March temperatures in Montana have risen five to seven degrees since the 1950s. As the graph shows, there is natural climate variability, and some years are cooler and wetter, like this year, but the upward trend is unmistakable, a trend that scientists say is consistent with global warming.

STEVE RUNNING: The final ramification of that is that our late summer stream flows in July and August are just dwindling to lower and lower stream flows, and that's really going to ultimately impact our trout populations and our fishing tourism.

HEIDI CULLEN: In Montana, that's especially true because water is so integral to the economy.

MAYOR JOHN ENGEN, Missoula, Montana: It doesn't matter whether if someone's actually dipping a line in the water and catching a fish. It's the restaurant meal, equipment, guide, and the hotel room. There's all that ripple effect.

HEIDI CULLEN: As mayor of Missoula, John Engen knows that healthy fish fuel a whole network of economic relationships that local populations depend on.

MAYOR JOHN ENGEN: If you think of the trout in this stream as the canary in the coal mine, if this stream isn't healthy, if it can't support this iconic species of fish and its varieties, can this place support another iconic species, which is the independent westerner?

HEIDI CULLEN: Another effect of warmer, drier conditions is increased wildfires.

STEVE RUNNING: Wildfire rates are going up dramatically. Insect epidemics are going up dramatically.

HEIDI CULLEN: Fewer subzero days in winter allow the voracious pine bark beetles -- normally killed off by the winter freeze -- to survive into another season. More beetles means more dead timber, making that timber even more combustible, more susceptible to forest fires.

MAYOR JOHN ENGEN: Our economy is affected by drought, mostly in terms of fire and the toll that fire takes on our collective resources in this state.

ROGER PIELKE, SR., University of Colorado, Boulder: Droughts have been very much a part of the western United States as far back as we can tell.

HEIDI CULLEN: Roger Pielke, Sr., is an atmospheric scientist at the University of Colorado in Boulder and has studied drought in the west. Whereas many scientists see the climate of the west shifting toward almost permanent summer drought, Pielke is reluctant to link drought to manmade changes in climate. He sees the looming water crisis as one result of population growth.

ROGER PIELKE, SR.: Multi-decade-long droughts have occurred in the past, so, regardless of how climates change because of human activity, we have to adapt and we have to mitigate as much as possible to try to reduce their impacts.

Lack of water for crops, sport

HEIDI CULLEN: Across Montana, one key adaptation strategy involves finding new ways to use available water more efficiently, but there are competing claims for that water. As they like to say out here, whiskey's for drinking, water's for fighting.

WALT SALES, Bozeman, Montana: We need to really start protecting not only the value of the water but protection of the use of that water for agriculture.

HEIDI CULLEN: Walt Sales is a fourth-generation farmer in the Gallatin Valley near Bozeman.

Agriculture contributes $2.4 billion a year to Montana's economy. But over the last decade, less snowmelt in the state has reduced stream flow at the time when farmers and trout need it most.

Sales values his water rights, but also understands the need to find balance with fishermen.

WALT SALES: We really like to see people enjoy our natural resources, but we also want that respect, knowing that this is somebody's property and it's a gift to the people of the state. And hopefully that will carry over with the recreationalists and others. And it has.

HEIDI CULLEN: However, Professor Running suggests the conflict is more pronounced than either side lets on.

STEVE RUNNING: This is a real tug-of-war between the recreationalists wanting water in the river and the landowners that are trying to grow crops and make a livelihood. And yet we don't have enough spare water to do both.

So the day is going to come -- in 20, 30, 40 years -- where there's going to have to be less irrigation of crops in order to keep water in the streams, and those landowners will have to go to dry land farming.

And I'm sure someone is going to have to compensate them for giving up water rights. It's going to be contentious.

HEIDI CULLEN: The competition for water could get even more contentious if coal-to-liquid technology, which converts coal to diesel fuel, takes off. Montana has 24 percent of the nation's coal reserves, and Gov. Schweitzer has been a proponent of coal-to-liquid, emphasizing the economic benefits and downplaying the fact that it is a water-intensive process.

GOV. BRIAN SCHWEITZER (D), Montana: We've announced a coal-to-liquid plant that will be built on the Crow reservation. That single plant that will employ 2,000 people will use about as much water as a project that has a couple of thousand acres of alfalfa, which would employ three or four people.

Governors coordinate legislation

HEIDI CULLEN: Gov. Schweitzer has allied himself with other western governors, signing the Western Climate Initiative.

TV COMMERCIAL NARRATOR: Solve it, and we help free America from its addiction to foreign oil.

HEIDI CULLEN: It calls for a 15 percent reduction in greenhouse gas emissions by 2020 and an increased use of alternative energy.

GOV. BRIAN SCHWEITZER: Bottom line: Coal has a CO-2 problem. And until we recognize and we begin mitigating that CO-2 problem, coal could be the energy of the past.

HEIDI CULLEN: Montana is also looking to capitalize on its abundant renewable energy sources, none larger than wind. The strong, steady winds here have the potential to meet the electricity needs of these 19 states.

So Montana is hoping for energy independence and economic growth, but not without legislative hiccups.

GOV. BRIAN SCHWEITZER: Change is difficult for people. Fundamentally, change scares people.

HEIDI CULLEN: Still, Montanans like Jenny West and Craig Mathews remain optimistic.

JENNY WEST: I hope that I can tell my grandkids someday that, you know, this is what it's like and it's been this way forever. You know, this is my life, this is my passion, and I want to be outside as much as I can. My business is counting on it.

CRAIG MATHEWS: If we lose trout fishing, we lose the headwaters of such great rivers as the Missouri and the Yellowstone. And we lose those very wild places that trout inhabit. And it's such a rich tradition, wild trout and wild places.

HEIDI CULLEN: People from Montana call their state the last best place, and they cherish their big sky and their big trout.

But they also recognize that the climate is changing, and so they're pursuing ways to adapt and to reduce. Some Montanans even say they're setting an example for other states to follow.

Learn more about this report at Climate Central's Web Site.