A post on the history and flies of the Wolf River got me to thinking about the Driftless. As you see, the area and the trout fishing we maybe take for granted has not always been what it is now. In fact, it really was not that long ago that Driftless fisheries were mostly stocked and not self-sustaining like they are now. Today, over much of the Driftless Area, if it is a blue line on a map, it holds trout. It has not always been that way, a fact we should celebrate but also understand that we should not take what we have for granted.
I will try to refrain from writing this like a scientific paper but there is certainly some important science to be discussed. And I think there are some pretty important historical lessons to be learned and to be kept in mind. But mostly it is a story of what we can do when we care enough to try to make things better. It is easy to take for granted what we have today but that came about because of a lot of resources were expended to "bring it back".
Let's Start with Some History
Early settlers arrived at a landscape we would scarcely recognize today. From Dave Vetrano's excellent article in the Driftless science review, upon arriving, they relatively quickly cut the trees down on the hillsides and converted much of the land to wheat production. By the 1880's, the area switched to the dairy production we see dominate today. These agricultural practices, poorly suited to the terrain and climate, resulted in massive erosion and flash floods. It forever changed the valleys of the Driftless area which were once mostly wet prairies. Likewise, the streams changed and became wider, shallower, and more entrenched (stream banks were higher, made of this "cultural sediment"). With wider, shallower streams also comes increased water temperatures. And with these changes, of course came changes to the fisheries.
By the 1930's, an effort to improve the landscape was launched by farmers of the area that asked the government for help. What became today's Natural Resource Conservation Service (NRCS) was spawned from their efforts to control soil erosion. For those that travel the Driftless, you may have stopped and read the sign just West of Coon Valley on Highway 14 that recognizes their efforts. Much of the improved fishing we see today is owed to the efforts of the area's farmers and how the word spread across the Driftless. This is not to say that the improvement were immediate.
Fisheries History and Improvements
Historically, the area would have been home to native Brook Trout (Salvelinus fontinalis) but as you probably well know, Brook Trout do not respond well to warmer temperatures. Brown Trout (Salmo trutta) were stocked as they were across much of North America and while they survive better in warmer streams, they mostly provided a put-and-take fishery with little natural reproduction. Over time, efforts to provide cover, narrow streams, increase their flow rate, and move fine sediments began to improve survival of these stocked Brown Trout. By the mid-1980's, the Conservation Reserve Program (CRP) paid farmers and other landowners for setting aside "highly erodible" lands and plant them to grasses that better hold soils and prevent erosion. Additionally, the Wisconsin Department of Natural Resources, Trout Unlimited chapters, the NRCS, local conservation groups, and others sloped and stabilized banks. The largest source of sediment delivered to these streams is the decades worth of cultural sediment that now fill the valley floors and make up the stream banks. Together, improved land use, streambank stability, and instream habitat are largely responsible for the fisheries we have today.
To explain the figure above from Lyons et al. 1996, coldwater streams tend to have few species - mostly trout and sculpin - that are tolerant of the cold water. As the streams warm, more species are able to survive in these conditions and species richness increases. As you can see, species richness decreased over time in Timber Coulee which illustrates how the stream water temperature decreased and habitat improved with the implementation of better land use practices and instream habitat improvements. These improvements have lead to the abundance of trout and other coldwater species we see today. They have also resulted in $1.6 billion of economic impact in the Driftless Area.
Current Threats
While today's picture is much rosier and we have come a long way, we also can not be complacent or think that the game is over and we have "won". Climate change, changes in land use often associated with agricultural commodity prices, growing populations, CAFOs, and other issues certainly pose threats. If history teaches us anything - and boy, it better - it is that what is here today can very well be gone tomorrow.
Most recently, the effects of flooding have been widespread and devastating to the people, houses, farms, and streams of the Driftless Area. Increased rainfall over the last few decades have resulted in higher groundwater tables which have resulted in more thermally stable streams which likely explains a significant portion of the improvement in wild trout populations. However the increase in extreme events has produced some of the largest floods in the history of an area that has endured its share of floods. Historic floods occurred on the Rush, Kinnickinnic, Coon Creek, and the West Fork of the Kickapoo among many other streams in just the last three years. With 24 hour rainfalls that are shattering historic records, the floods have been some of the largest in history, despite generally improved land use.
Land use in the Driftless is changing in two important ways. First, there are more recreational owners which are generally taking land out of agriculture - generally a pretty good thing for trout. Second, farms are getting larger as are the row crop agriculture fields, a particular issue on the steeper hillslopes of the Driftless. Commodity prices drive much of the land use in the Driftless and elsewhere, particularly as CRP payments have failed to keep up with commodity and rent prices. In Wisconsin, CRP enrollment dropped by over 60% from 2007 to 2016 (source) which represents one of the largest percent declines in the country. A quick look at one of the many websites that show aerial photos over time will show that in places, grassed waterways and other "set aside" lands that are useful in preventing and trapping sediment have been reduced as more row crop agriculture (source). As the Iowa State publication states, there has been a rapid shift to larger farms (more cows per farm) and every HUC-8 watershed in the Driftless saw an increase in acreage of row crops.
What it means?
What the effects of these land use changes have been and will be are not 100% known but it does not require a Ph. D. in fisheries science to have a pretty good idea that the outcomes of climate change, fish kills, floods, and increases in row crops and decreases in CRP acreage are probably not great for trout. Floods have made many streams wider and shallower - much like the cultural sedimentation of the 1800's and early 1900's had done. While this is totally anecdotal, I think we are seeing some long-term reduction in water quality from their peaks. Yes, this is anecdotal but I would assume the SWIMS and other sources might have some evidence but it has been my experience that many of the hatches of the Driftless have been reduced. The Hendricksons, Sulphurs, and March Browns that used to be the dominant hatches are much reduced and more "hit or miss". The Hexagenia limabata hatches on Black Earth Creek have largely gone the way of the (non-avian) dinosaurs according to those I know and trout numbers are down on the river from the 1990's when I fished it regularly. Today, the cranefly and a few caddis hatches are reliable and numerous whereas other hatches have not been what the once were, at least in my experiences. The reduced hatches and the evidence for them is a future post but I think it is a pretty significant happening in the Driftless and elsewhere. There is pretty good evidence of the loss of insects from other places and is something that bears more investigation.
Improvements in environmental quality have occurred - maybe not steadily - since the 1930's in the Driftless. These changes have been responsible for a fishery and tourism industry that continues to increase in value. Improvements to streams and access to them have supported an important increase in the areas fisheries and the tourism economy of the region. It would be a shame to see to these efforts - and the economy they support - be sidetracked by fish kills, reductions in water quality, and ultimately fisheries quality. Yes, we should be happy - hell proud - of the great changes that have created self-sustaining trout streams from streams that were once thought to be beyond repair. But we also should not take these improvements for granted and these improvements are not permanent.
I do not write this to be a "downer" but it will take effort to maintain what we have and we need to stay diligent and not take what we have for granted. Stresses to our environment and its streams are not going away and seem to be changing and increasing. The fisheries of the Driftless today are the result of a lot of hard work over many decades. These are the good old days in so many ways but they do not remain without effort and perseverance. Be part of the solution - get involved, be vocal, and support groups that are working to help maintain and improve our environment.
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