ASIAN CARP, SCHMASIAN CARP! – Meet the Meanmouth

I’ll never forget the first fish I ever caught on the St. Croix River. I was seven years old. My dad and I were trolling one warm summer evening. He kept our seven-and-a-half-horse Evinrude putt-putting along at its slowest possible speed. Still, my little Mirro-lure vibrated more than swam as it bucked the current.

I got a strike. It could have been any of seven or eight species of game fish commonly caught on lures in the St. Croix. Whatever it was, at that tender age I was sure it was a monster. After a minute or two of awkward pulling and reeling I lifted the splendid barely-one-pound specimen out of the water.

The fish’s glistening flanks were surprisingly dark. The sun, about to settle into the bluff treetops on the Minnesota side, brought out olive-gold highlights and muted vertical stripes. I thought it was the most beautiful, exotic creature I’d ever seen. I knew it was a bass, but my dad, grinning proudly, made sure I knew exactly what kind of bass. “That, son, is a keeper!—a beautiful St. Croix smallmouth black bass.”
     I still caught a few bass. But this time, some-
     thing was radically, shockingly, different.

UPS AND DOWNS

Smallmouth black bass (Micropterus dolomieu)

In 60-plus years since that magical moment, I've caught at least a thousand more smallmouth black bass in the St. Croix. It’s the species the river is best known for, perfectly suited to its clean, cool currents, sandy-to-gravely bottom, rocky crags, eddies and deep pools—one many credit as, pound for pound, one of the scrappiest game fish in the world.

Many of my favorite fishing spots lie along a secluded slough that diverts for a mile or so into the Wisconsin-side woods before rejoining the river. I'd been noticing that for some years, with the water level reaching its customary late-summer low earlier and earlier, it’s been getting harder to float into it after late June.

One early-July day a few years back, I found the slough already cut off from the river's flow. I had to drag my canoe over sandbars and through muddy shallows to get in. The backwater’s now-stagnant waters were murky, and weeds I'd never before seen on the river thrived.

I was concerned about whether the bass would still be there—usually only carp and a few intrepid pike tolerate these unappealing waters. Surprisingly, I still caught a few bass. But this time, something was radically, shockingly, different.

Largemouth black bass (Micropterus salmoides)

These were all largemouth bass. Or at least they seemed so to my unskilled eye. The extension of the jaw's upper, maxillary, bone to a point clearly behind the fish's eye, and a dark swath running lengthwise along each side (rather than the vertical-stripe pattern typical of smallies) both suggested it.

So where did these “bucketmouths” suddenly come from? Where did the smallies go? How could such a changeover happen so fast? Was this an irreversible trend—perhaps yet another close-to-home sign of global climate change? Had I seen the last of this handsome, valiant breed—the fish that had defined piscine beauty for me a half century ago?

     I caught seven little bass in the slough. 
     But this time I couldn’t tell what they were.

SPLIT THE DIFFERENCE
In the past few years, I’ve once again caught smallies in the slough, but also the occasional largemouth. The difference hasn’t seemed to depend strictly on water level and quality, so I’m still wondering what’s going on.

This summer of 2015 has been an extraordinary one for this part of Minnesota—relatively cool temperatures and plenty of rain. For the first time in memory, my favorite slough has been navigable all summer long—and well into the fall. I’ve been fishing in there seven or eight times, and have delighted in catching lots of smallies, many of them that amazing dark color that so struck me when I was a boy. And good-sized ones at that.

Yesterday, on my latest outing—likely last of the season—I caught seven little bass in the slough. But this time something was quite different. I couldn’t tell what they were. Every single one had some of the characteristics of a smallmouth and others of a largemouth. Some of those traits fell halfway in between.

Black bass caught and released in St. Croix River, October, 2015

Smallmouth and largemouth black bass

Instead of the maxillary extending back to the middle of the eye’s pupil (smallmouth) or well behind the eye (largemouth), it extended just to the back of the eye. Rather than a compound dorsal fin (smallmouth) or one with a distinct break between the forward, spiny part and the rear, softer part (largemouth), there was something halfway in between.

Instead of vertical stripes and bronze highlights (smallmouth) or a mossy green hue with a dark horizontal stripe (largemouth), these specimens had fairly uniform gray-green coloring with reddish dorsal and anal fins and tail.

   If the meanmouth is really here, what does that 
   say about the health of our beloved St. Croix?

MEET THE MEANMOUTH
So, have I been witness, in the course of just three or four years, to the evolution of a new, hybrid black bass species on the St. Croix? This cross has been noticed and documented elsewhere; it’s called the meanmouth*. More commonly considered the offspring of a smallmouth and a spotted bass (Micropterus punctulatus), meanmouths of the small-/largemouth version do exist, though they are thought to be “extremely rare due to the difference in habitat preferred by the respective parents.”**

But that would clearly support the case for meanmouths evolving in the St. Croix, because both habitats are present: clear, cool, flowing smallmouth waters during half the summer; still, murky, warm largemouth waters the rest of the summer. Wouldn’t that be the ideal habitat for a hybrid?

While we St. Croix River aficionados tremble at the thought of an impending invasion of Asian carp—bigheads, silvers or both—here, sneaking in under the radar, comes the meanmouth. Not invasive, nor destructive (that we know of), but of concern nonetheless.

If the meanmouth is really here, what does that say about the health of our beloved St. Croix? I don’t know if the Minnesota and Wisconsin DNRs are aware of these apparent changes in the river's black bass population, but perhaps more observations from other fishermen—preferable some with more ichthyological knowledge than I possess—would help them at least to quantify and track the extent of the changes.

*The origin of the name "meanmouth" is recounted in this quote from In-Fisherman:
“The term “meanmouth bass” was born when Childers observed a school of largemouth-smallmouths attacking a female swimmer. “The bass leaped from the water and struck her on the head and chest,” he wrote, “and drove her from the pond.” On another occasion, he watched meanmouths attack a dog that ventured into shallow water.”

** BassFishingGurus.com 

HOW TO BE IN THE MOMENT – 101 Little Tips

TIP #75 
Make a quiet entrance.

Nature's a wary host…when she knows you're coming. 

In the wild, declare special times for slow, silent movement. Be still; walk or paddle lightly; peer slowly around the next bend.
 

HOW TO BE IN THE MOMENT – 101 Tips

TIP #4 
Look under things.

There's a whole world of critters that live under things—
leaves and rocks and logs.

There they tunnel and nest, beyond the reach of all but the
craftiest foe—and most curious friend. 

Whichever you are, you must be quick.
 

BETCHA CAN'T FIND… – A Simple Game of Observation

Starting when my kids were about three and four years old, they'd spend their summers with me. I did my best to keep them busy learning and having fun. While I worked, they were in summer art programs, at day camp or with friends whose parents were around during the day. Evenings and weekends we also had lots of fun, but sometimes we’d find ourselves with some time to kill—sitting at the laundromat, on long trips in the car, or waiting for Grandma.

 

To make the best of that time, we invented a simple game of observation. It usually works best outdoors, but it can be fun indoors too. The more varied and cluttered the view, the better. I don’t think we ever named it, but, after playing it once, all I had to do to declare the game underway was to say “I’ll bet you…can’t…find a…," and fill in the blank with the name of any object I knew we could all see. I’d always say the words very slowly, sort of dramatically, which became their cue to dial up their sharpest eyes.

 In order to challenge them for more than a few seconds, I had to find more and more minute details.

Sounds pretty simple, right? Well, at first it was. But my kids proved so good at it that, in order to challenge them for more than a few seconds, I had to find more and more minute details or things that were visible only intermittently (like a waving flag that showed between two buildings only when billowed by the wind).
Since the object was for one sibling to find the object before the other, it became an exercise very much like speed reading—scanning a visual “lexicon” for that one key “word.”

...it takes a little time, which, after all...is the greatest gift we can give our loved ones…and ourselves.

Like anything so wonderfully simple, I’m sure this game wasn’t our exclusive invention. There could be any number of variations; any format will do. The key is to use one’s sight like a laser to cut through the flashy, loud, obnoxious foreground layer that so often clambers for our attention, and see some of the other layers of rich detail life lavishes on us.

The beauty of Bet You Can’t Find… is that the only equipment you need is your eyes, something those of us lucky enough to have good vision take with us wherever we go. And, of course, it takes a little time, which, after all—one of the main points of One Man's Wonder—is the greatest gift we can give our loved ones…and ourselves.

HOW TO BE IN THE MOMENT – 101 Little Tips

 TIP #54

Be aware of negative space.

    In Nature, as elsewhere in life, we can see more if we look not just at things, but also at the spaces between things; not just at the pattern, but breaks in the pattern.
    Among other things, this skill will help you find critters in
water or deep woods.

HOW TO BE IN THE MOMENT – 101 Little Tips

 TIP #6

Just when you think you've seen something interesting, 
keep watching for another 30 seconds.

Photo by Artequa – http://www.flickr.com/photos/puntodevista/with/118666362/

WHAT WHALE? Observing the Invisible

Nano-scientists are studying and even making things out of sub-atomic particles too small to see, even with a microscope. A little closer to home, I can tell there’s a big carp darting away from the bow of my canoe or a hungry smallmouth hunting for supper even when the water’s too murky to see them.

How? The same way those scientists keep track of those quarks and fermions; the same way you know about the wind even though it’s invisible and you’re inside your house where you can’t even feel it.

 Often the best—sometimes the only—way of seeing something is by the effects it has on something else. In the case of the wind, I get my clues from the trees, a flag or a leaf tumbling across the yard. With the carp, the giveaway is the subtle bulging of the surface where the water’s displaced by the fish’s movement. And you know bass are hunting when you see schools of shiner minnows breaking the water’s surface in flight.

This method of “indirect observation” has worked well for me in locating sloths in Costa Rican forests and tracking whales in the Sea of Cortez. Again, the animal may be all but invisible, so the trick is not to look for it directly. You look for the other things that give it away.

     With this expectation, it’s like the 
     mother of all Where’s Waldo pictures.

For sloths, it's the distinctive cecropia trees whose leaves and resting places they seem to prefer. And I try to find subtle breaks in the pattern of dark, narrow branches and the light spaces between them.

For the whale, the giveaway might be its “fluke prints,” the surprising, wave- canceling circles caused by the upflow of water from the creature’s up-and-down tail movements.

Indirect observation involves a subtle shift in one’s mindset. If you’re looking for a sloth, you’ve set your unconscious visual filter to rule out anything that doesn’t have brown, shaggy fur and four legs. With this expectation, it’s like the mother of all Where’s Waldo pictures; let’s say it’ll take you a while.

But if you switch the filter to a coarser mesh, that is one set to look for more generalized information, like breaks in patterns, you improve your odds considerably. If you’re bird watching, this means adjusting your eye-brain filter to focus not so much on spotting the birds themselves, but on noticing movement. It’s a pretty fine distinction, but it works.

"I believe only in what I do not see." Gustave Moreau (French, 1826-1898)