Drove to the St. Croix River early this morning hoping to pick up a few new redhorse species. I left at 4:30 a.m. so I could be fishing by 7, though the two‑hour drive always turns into a bit more with my usual pit stops.
I started at Osceola Landing with my standard setup: 6 lb line, a roughly 16‑inch leader, and a size 8 hook baited with a small piece of nightcrawler. I caught a small Freshwater Drum first, followed by a Golden Redhorse. Both were familiar species, so no new additions to the list.
The heat and lack of sleep caught up with me, so I took a 45‑minute nap and then grabbed lunch. That helped a lot. I spent the afternoon fishing at Interstate State Park on both the Minnesota and Wisconsin sides. I got a few bites but nothing hooked up, which was frustrating after such a long trip.
On the way home, I stopped in Hastings to try salvaging the day with a common carp. I did catch a fish there—but it turned out to be a large bullhead instead of a carp.
Not the day I hoped for, but still a couple fish and some new water and beautiful scenery explored.
Ever since I started fishing avidly in April, people have been giving me advice about which Mississippi River pool to fish for various species. If you want Bowfin, try this pool. If you want Sturgeon, try that pool. Looking for Walleye? Fish another pool.
I was vaguely familiar with Mississippi River pools but became curious about exactly what they were. I knew they were stretches of water associated with locks and dams on the Mississippi River, but surely they had not always been there. How many pools are there? Where are they located? And when were they built?
The Mississippi River pools begin in Minnesota, where the Mississippi River originates at Lake Itasca State Park. The pools are numbered consecutively as you travel downstream. The first Mississippi River navigation pool is Pool 1, located in the Minneapolis-St. Paul area. It extends from Lock and Dam 1 (the Ford Dam) upstream to St. Anthony Falls in Minneapolis.
A pool is the stretch of river between two locks and dams. Each lock and dam creates a backed-up section of river known as a pool. The pools are numbered in sequence as you move downstream. Pool 1 is in Minneapolis, Pool 2 is near St. Paul, Pool 3 is near Hastings, and Pool 4 includes Lake Pepin, one of the most popular fishing destinations in the Upper Midwest.
The last numbered Mississippi River navigation pool is Pool 26, located just north of St. Louis. South of Pool 26, the river becomes open river and flows freely all the way to the Gulf of Mexico without additional navigation pools.
Back in Mark Twain’s day, there were no Mississippi River pools. The Upper Mississippi was a free-flowing river with islands, side channels, wetlands, sandbars, and highly variable water levels. Commercial navigation was often difficult and sometimes impossible during periods of low water.
The locks and dams that created the pools were built primarily to provide a reliable 9-foot-deep navigation channel for commercial barge traffic between Minneapolis and St. Louis. The dams create deeper pools of water, while the locks act like elevators that raise and lower boats between pools of different elevations.
Most of the locks and dams that created Pools 1 through 26 were built during the 1930s, with the majority completed by 1940. A few notable exceptions include Lock and Dam 19 at Keokuk, Iowa (completed in 1913), Lock and Dam 1 in Minneapolis (1917), and Lock and Dam 2 (1930). The project transformed the river into what the U.S. Army Corps of Engineers has called a “stairway of water,” with locks functioning as elevators that move boats and barges from one pool to the next.
The locks and dams have had both positive and negative effects on the river ecosystem.
Negative impacts include the loss of a free-flowing river, increased sedimentation in backwaters, altered fish habitats, changes to islands and side channels, and the spread of invasive species. The navigation system created a more connected waterway, making it easier for some invasive aquatic species to move throughout the river system.
On the Positive side, the locks and dams created a reliable commercial transportation corridor, which was their primary purpose. They reduced transportation costs and helped farmers and industries throughout the Midwest reach national and international markets. Construction of the system also provided thousands of jobs during the Great Depression.
The pools created recreational opportunities since stable water levels support boating, fishing, waterfowl hunting, birdwatching, and other outdoor activities. Although some natural river habitat was lost, the pools also created extensive backwaters, marshes, side channels, and aquatic vegetation beds that support many species of fish, migratory waterfowl, bald eagles, and other wildlife.
In addition, many river communities upgraded their sewage-treatment and drinking-water systems after the pools were created because water-quality problems became more apparent in slower-moving water.
Finally, while the lock-and-dam system was not designed for flood control, it does provide more predictable river conditions for navigation and recreation than existed before the dams were built.
Overall, the locks and dams transformed the Upper Mississippi from a shallow, often difficult-to-navigate river into a dependable transportation corridor while also creating many of the fisheries, backwaters, and recreational opportunities that anglers enjoy today. The trade-off was the loss of much of the river’s natural, free-flowing character. Many of the productive fishing areas that exist today are a direct result of the pool system, while many of the river’s original sandbars, islands, and natural channels have been altered or lost.
Since I started avidly fishing in April, I’ve become aware of the geography and character of water in a way I never had been before. I’ve lived in Rochester, MN for 37 years (with two years away), and of course I’ve always known the Zumbro and Root Rivers and the reservoirs — Willow Creek, East Kalmar, Silver Creek, Silver Lake, and South Landfill. Birdwatching made me familiar with the reservoirs over the years.
But when it came to the rivers themselves, I honestly couldn’t have told you much about their routes through the county. Now I find myself regularly thinking about them — where they flow, how they branch, and where good fishing might be. I’ve started paying attention to river features like riffles, runs, and pools, and imagining where each might be hiding fish.
The figure below shows the major watershed basins of Minnesota. The Cannon, Zumbro, and Root Rivers all fall within the Lower Mississippi River Basin, even though they aren’t individually labeled on the map. Seeing the basin laid out like this has helped me understand how these rivers fit into the larger landscape of southeastern Minnesota — and what species I might find as I explore them. Fishing has completely changed the way I see water.
I was shooting for Carp again. They have been surprisingly frustrating to catch.
Today was hot as heck—temperatures were in the upper 80s, with sustained winds of 20–35 mph. Still, I felt good about the day. In the morning, I cooked a nice meal of chicken paprikash and Brussels sprouts with bacon and onions. Then, in the afternoon, I met with my advisor from the Office of Staff Services to discuss and plan my retirement this October. With both of those tasks accomplished, I felt I had earned a little time to escape and do some fishing.
My first stop was Silver Lake, where Silver Creek enters the lake on the east side. Several people had reported catching carp there, so I thought it was worth a try. Unfortunately, I didn’t get a single bite. After about 30 minutes of sweltering heat and relentless wind, I decided to move on.
I headed downstream to the tailwaters below the Silver Lake dam. Once again, I targeted Carp using the same simple setup: 6-pound line, a light split shot, a size 8 hook, and a small piece of worm. Below the dam were a series of riffles, a run, and a deeper pool that looked promising.
Almost immediately, I started catching fish. The first was an average-sized Black Bullhead—not a new species for me, but always fun to catch. The next fish, however, was much more exciting. It turned out to be a Golden Redhorse, a species I had never caught before. It was a decent-sized fish and put up a respectable fight before coming to hand.
Golden Redhorse
The action continued for the remaining hour that I was there. I caught six more Black Bullheads and a Bluegill, but despite all the activity, I still failed to land a Carp.
That’s okay, though. I’m sure I’ll catch one eventually, and the Golden Redhorse made the trip worthwhile. Adding a new species to my list is always exciting.
I’d estimate that roughly three-quarters of the fish I’ve caught in my life have come on an earthworm, with the remainder taken on various lures. When lures aren’t producing and I simply want to catch something—anything—I’ll thread a worm onto a small hook under a bobber and, more often than not, end up happily holding a bluegill. In the past couple of months, I’ve also come to appreciate how effective worms can be on bottom rigs, particularly for benthic species like redhorse and suckers.
That reliability comes at a cost. It isn’t unusual for me to spend twenty dollars a week on nightcrawlers and red wigglers from local sporting goods stores. I tend to buy both, even though I usually end up cutting pieces from the larger nightcrawlers. The worms don’t last long. Within a day or two they begin to rot—or “necrose,” in pathology terms—and I start to worry about the smell taking over my car. I usually leave the container on top of the garage trash can and, only when I’m sure they’re dead, toss them into the backyard, though I’ve begun to question why I feel the need to wait.
That habit, and the expense, got me thinking about whether I could simply dig worms in my yard. The answer, unfortunately, is no—the soil is too dry and poor to support many. That realization brought back a memory from my childhood. My dad, an avid organic gardener, once raised worms in our basement in a large trash can. I can still picture what went into it: potting soil, shredded newspaper, and bits of lettuce and other kitchen scraps. At the time, it seemed like an odd project, but his goal wasn’t fishing. He was trying to improve the thin, dry soil of Hays, Kansas.
What he had set up was more sophisticated than I appreciated then. In effect, he had created a small, self-sustaining ecosystem. The shredded newspaper provided a light, breathable carbon source, while the potting soil gave the worms structure and grit for burrowing. The food scraps broke down steadily, feeding not only the worms but the entire microbial community that supported them. In the cool, dark environment of the bin, the worms thrived and multiplied.
His real objective lay outside the basement. The soils around Hays tended to be clay-heavy, low in organic matter, and prone to compaction, with a pale, almost lifeless appearance. By adding both compost and worms, he gradually transformed that ground. The worms tunneled through the soil, aerating it and improving water infiltration, while pulling organic material downward and leaving behind nutrient-rich castings. At the same time, the compost contributed carbon and nitrogen and improved the soil’s structure. Over time, the tight, light-colored soil gave way to the dark, crumbly loam I remember from his garden. Looking back, it’s clear that he was practicing a kind of long-term soil restoration decades before “regenerative gardening” became a popular term.
At the time, I didn’t connect any of this with fishing, but in retrospect it ties directly to the bait I rely on so heavily. Not all worms are the same, and the differences matter. European nightcrawlers (Dendrobaena hortensis) occupy a kind of middle ground: hardy, active on the hook, and versatile enough to catch everything from panfish and trout to bass, walleye, and catfish. Red wigglers (Eisenia fetida) are smaller and reproduce quickly, which is part of what made them so useful in systems like the one my dad maintained; as bait, they excel for panfish and trout, though their size makes them less appealing for larger fish unless used in multiples. Canadian nightcrawlers (Lumbricus terrestris), by contrast, are the classic large bait worm—the kind found in nearly every bait shop. They are ideal for bigger fish like walleye, bass, and catfish and are especially effective on bottom rigs, but they don’t lend themselves to cultivation, living deep in the soil and resisting attempts to raise them in contained systems.
Taken together, these different worms reflect both sides of the story: the biology of the soil my Dad was working to improve and the practical realities of catching fish. As I keep buying them by the dozen, I can’t say the investment hasn’t been worth it.
While fishing the other day, I found myself thinking about how river water quality compares to when I was a kid in the 1960s and 1970s. It seems much improved today, even though there is still room for progress.
The firstEarth Day was held on April 22, 1970, when I was just 11 years old. I remember it being a big deal, but I had little understanding of what it was about—at the time or even until recently, when I read more about it. One of the most important outcomes, especially for those of us who fish, was the passage of the Clean Water Act.
The Clean Water Act grew out of decades of largely unsuccessful efforts to control water pollution in the United States. Earlier laws, such as the 1948 Federal Water Pollution Control Act, relied mostly on voluntary cooperation and had minimal enforcement power. By the 1960s, many rivers and lakes were heavily contaminated with industrial waste and sewage. Public concern reached a peak after events like the 1969 Cuyahoga River fire, when a polluted river literally caught fire.
In response to this environmental crisis and rising public pressure, Congress passed sweeping reforms in 1972 that became known as the Clean Water Act. Despite a veto by President Nixon, Congress overrode it with strong bipartisan support. The law marked a major shift: rather than relying on voluntary measures, it made it illegal to discharge pollutants into U.S. waters without a permit and established a national regulatory system to control pollution.
Over time, the Act has been strengthened and refined. Amendments in 1977 expanded controls on toxic pollutants and industrial discharges, while changes in 1987 placed greater emphasis on state-led programs and addressed pollution from runoff sources.
Today, the Clean Water Act remains the foundation of water pollution regulation in the United States. It reflects a fundamental transformation—from weak, fragmented efforts to a strong federal framework designed to protect the nation’s waters.
Importantly, the Act applies not only to the rivers and lakes where I fish, but also to coastal waters and estuaries—essentially the country’s interconnected surface waters.
For more information on the history of the Clean Water Act (as well as the EPA and the Clean Air Act), see this excellent video.
Woke at 5 a.m. to head back to Northfield below Ames Dam, hoping to catch a Redhorse species—though I would have gladly taken a Bigmouth Buffalo or Carp. I was set up and fishing by about 8 a.m.
I used a simple bottom rig: 6‑lb monofilament main line and leader, a ½‑ounce sliding egg sinker, barrel swivel, and initially a size 8 hook (later switching to a size 10).
After about 20 minutes, I landed a Freshwater Drum. Soon after, I hooked what appeared to be a Redhorse but lost it at the shoreline. The same sequence repeated—another drum, then another lost Redhorse. At that point, I downsized from a size 8 to a size 10 hook to see if it would improve hookups.
That adjustment paid off. I was thrilled to land my first Redhorse—specifically, a Shorthead Redhorse. Interestingly, it didn’t put up much of a fight initially, but as it neared shore, it surged with surprising strength.
Shorthead Redhorse
Unfortunately, the fish was gut‑hooked and visibly bleeding. I chose not to attempt hook removal; instead, I cut the line and released it. My understanding is that cutting the line is generally the best option in these situations, especially when there is bleeding. Attempting to remove a deeply embedded hook in species like redhorse—whose gill arches are delicate and whose throats are narrow—can cause far greater damage.
Research supports this approach. Once a hook passes beyond the tongue pad, removal often leads to tearing of tissue or injury to the esophagus or gill arches. Cutting the line avoids additional trauma. In many cases, the hook will corrode, become encapsulated by tissue, or eventually pass. Studies in similar species (catfish, suckers, carp) show significantly higher survival rates when anglers cut the line rather than attempt removal.
Redhorse are especially prone to gut‑hooking because of how they feed. They inhale food rather than striking it, feed head‑down so the hook slides inward easily, and produce a very subtle bite that’s easy to miss—particularly when using worms, one of their preferred foods.
The fish itself was striking. The fins were a vivid, almost glowing red—peak June coloration. Shorthead Redhorse are among the most beautiful freshwater fish in Minnesota. This coloration comes from carotenoid pigments acquired through their diet, with intensity enhanced by spawning‑season hormones.
These bright red fins likely serve several purposes:
Spawning signal – helping fish locate each other in often murky water
Species recognition – subtle differences distinguish species within the genus
Health indicator – brighter coloration often reflects a well‑fed, healthy fish
This one clearly checked all three boxes—the most visually striking fish I’ve caught in some time.
The fact that I prefer fishing from shore has nudged me toward rivers—and that, in turn, led to an unexpected realization: rivers seem to hold an extraordinary diversity of fish. That observation made me wonder whether rivers actually harbor more species than lakes. It turns out they do—and it’s not even close.
So why is that? The short explanation is simple: rivers create more ecological niches per mile than lakes, and niches create species. This reflects a broader ecological principle. Ichthyologists have shown that lotic systems (flowing water) tend to support greater species richness at local scales than lentic systems (still water).
Again, why is that? Rivers generate a remarkable range of habitats—riffles, runs, pools, backwaters, floodplains, estuarine transitions, springs, tributaries, and headwaters. Each of these environments supports different species. In addition, rivers contain fine-scale microhabitats (eddies, seams, root wads, undercut banks) that further expand ecological opportunities. Lakes simply lack this degree of structural complexity.
Rivers also function as connected networks spanning large geographic areas. This allows for dispersal, isolation, recolonization, and ultimately speciation and helps explain why entire groups—darters, shiners, redhorse, and suckers—are predominantly riverine and have diversified into dozens (or hundreds) of species. Lakes, in contrast, are more like isolated bowls: excellent for stability, but less conducive to generating new species.
This pattern is especially evident in the southeastern United States. River systems such as the Tennessee, Cumberland, Mobile, and Apalachicola basins contain the highest freshwater fish diversity in North America—and among the highest in the world outside the Amazon. These are river systems, not lake systems.
So how large is the difference? Of the roughly 800+ freshwater fish species in the United States, the vast majority are associated with rivers and streams. Many are endemic to single watersheds. True lake-specialist species are relatively rare (for example, some ciscoes and pupfish), numbering only a few dozen. By contrast, river-dominated groups are extraordinarily diverse: redhorse (15+ species), darters (200+), minnows (300+), suckers (70+), and madtoms (30+).
None of this diminishes the importance of lakes—they excel in other ways. Lakes support high biomass, offer stable environments, and sustain large, iconic predators such as walleye, pike, and lake trout. They are also central to recreational fisheries. But they are not the primary engines of speciation.
If your goal is species diversity, rivers and streams are the heart of freshwater biodiversity in the United States. Lakes are wonderful—but rivers are where evolution does some of its most creative work.
I woke up at 4:30 a.m. and headed back to the Root River in Preston, hoping this would be the day I landed a Brown Trout (Salmo trutta). It took about 45 minutes to get there, and I was fishing by 6:00 a.m. It was a little chilly, but a really nice morning—sun, scattered clouds, almost no wind.
This stretch of the Root River is fairly narrow and probably not very deep. The night before, I’d seen some kids swimming in it, and they were often able to stand with their heads out of the water. I’d guess it’s about 30–40 feet across in most places. Still, it clearly holds fish. On earlier trips I had already caught Rainbow Trout, Common Shiner, Creek Chub, and White Sucker.
I started out throwing a couple of small inline Panther Martin spinners. I should have written down the exact size and colors, but didn’t. One was all silver, and the other had green, red, and silver—at least I think that’s what it was. Probably the next-to-smallest size. I made around 40 casts without a single bite. Eventually I decided that was enough persistence for one lure.
The water looked a bit murky, probably from heavy rains the day before, and I began to suspect the fish just weren’t seeing the spinners very well. Or possibly they were seeing them and choosing to ignore them—always another possibility. Either way, I switched back to the bottom rig that had worked well on my last two trips: 6 lb monofilament, 1/8 oz egg sinker, swivel, about a 12-inch leader, and a size 10 hook with a piece of worm.
The action was pretty slow, but then I finally caught a Brown Trout. Not a huge one, but a nice fish and, more importantly, a new species for me. I posted it to iNaturalist and, I’ll admit, kept checking back waiting for confirmation. About eight hours later someone confirmed that it was a Brown Trout. I also picked up another Common Shiner along the way.
Brown Trout
After that, I switched things up and headed over to the Mississippi River to try for Bowfin. That’s a completely different game—different rod, different rig, different mindset. No luck this time, but that’s probably a story for another day when I actually catch one.
With the Brown Trout, I’ve now completed the trout “triumvirate”: Rainbow, Brook, and Brown. I’ve caught Rainbow in Minnesota and Washington, Brook in Washington, and now Brown in Minnesota. Next on the list are Lake Trout, Splake, and Tiger trout—because apparently there is always another fish to chase, and apparently I am fine with waking up at 4:30 a.m. to do it.
I went to the South Fork of the Root River in Preston, Minnesota this afternoon and evening hoping to catch a Brown Trout for my species list. I used the same bottom rig I had the other night, baited with a bit of worm. Once again, I ended up with something different—LOL. I landed a nice Rainbow Trout and hooked a couple more fish that I couldn’t bring in. One of those might have been a Brown Trout, but I can’t say for sure. I stayed from about 5:30 to 8:30 p.m., getting occasional bites, though I missed most of the hooksets. Just as I was about to call it a night, I caught one last fish that I suspected might be something new, but I wasn’t sure what it was.
Common Shiner
iNaturalist identified it as a Common Shiner, which immediately made me wonder what exactly that was. A little research cleared things up. Shiners are part of the Minnow family (Cyprinidae), the largest family of freshwater fish in North America. The Common Shiner (Luxilus cornutus) is one of the more widespread species and is typically found in clear streams with moderate current—exactly the kind of water I was fishing. They usually have a silvery body with a darker back and tend to grow to about 2–6 inches. The one I caught was right around 6 inches.
I also learned that while all shiners are minnows, not all minnows are shiners. “Minnow” is a broad term that includes shiners, daces, and chubs, among others, while “Shiner” generally refers to these small, silvery, often schooling fish. Common shiners are a bit more robust than some of the other shiner species and can be an important forage fish for larger predators. Overall, it was a fitting and interesting catch for that stretch of river—even if I’m still looking for that Brown Trout.
OneHundredFish 