RIVER DANCE – The Art of Survival

The sultry summer sun was just dropping behind the Franklin Avenue Bridge before nestling into the treetops for the night. Except for the lazy current, the Mississippi seemed as still as the saturated air.

RAINDROPS FROM BELOW

Then I noticed the small circular ripples—lots of them. They pecked the water like a light rain as far as I could see. But the sky was perfectly clear.

Dialing up my vision to close-up range, I could tell there was something different about these ripples. Instead of the little rebound that swells up after the impact of a raindrop, here there seemed to be a depression, as if from a tiny pluck at the elastic surface from below.

              I noticed that the shiners were 
              not just dining; they were dinner.

I squatted on a rock to see if I could see what was causing them. Sure enough, there were two-inch-long shiner minnows rising to the surface. Some appeared to be taking tiny gulps, pulling gently at the surface membrane; a few darted to the surface, even breaking part-way through it; a couple of them actually jumped in little arcs like miniature dolphins.

While each break in the water’s surface seemed mute, together, by the thousands, they gave off a barely perceptible hiss like a light rain shower. I figured the minnows must be feeding on something.

Then, in a span of about twenty seconds, Nature dramatically unveiled the whole mystery. First, I noticed that the shiners were not just dining; they were dinner. Small groups of them would dash desperately in one direction, some even skittering across the surface as if hoping to take flight.

Though I couldn’t see their predators, subtle wakes pushed up by their torpedo lunges gave them away—I'd have bet they were smallies—smallmouth bass.

ON GOLDEN WING
Just at that moment, the sun broke through into the space under one of the bridge arches, flooding the scene with its warm, golden light. And there, suddenly backlit against the dark wooded bank on the other side of the river, was the reason for the whole drama: millions of insects, so small I hadn’t noticed them when they were in the shade.

  The river, like a giant roll of flypaper, snagged 

  and held the unwary until they were gobbled up.

Now, like a pointillist’s cloud, they illuminated the air. They moved randomly, except when some would billow, swept by a breeze's gentle hand. The river, like a giant roll of flypaper, snagged and held the unwary until they were gobbled up by the shiners.

A few minutes later the sun finally set behind the trees, and the insects once again evaporated into shadow. But, as if drawn to my curiosity, a few of them presented themselves to me, landing on my clothes and skin. They were tiny golden wasps no more than about an eighth of an inch long.

CHANGING LENSES

As incredible as this event was, it wasn’t the first time I’d witnessed such a predator-prey spectacle. Many years ago, while fishing near Puerto Vallarta, I found myself in the midst of a feeding frenzy on a somewhat larger scale.

Schools of herring-like bait fish were being chased by larger predator fish, which became prey for still-larger tuna, which, in turn, were hunted by Homo sapiens—all this while several species of diving birds exploited the carnage for a meal of their own.

PHOTO: Mike Baird

      
It’s amazing enough to study a single creature or witness one phenomenon occurring in Nature. Next time you’re outdoors, no doubt you’ll do that, spotting critters large and small. But try sometime, as I did that evening on the Mississippi, playing with the lens of your vision.

    See if you can spot the gripping predator-prey 
    drama constantly playing out all around you. 

Use wide-angle to see the broad, generalized movements and patterns. Then focus in on just one detail to see what clues it might provide to understanding the big picture. And see if you can spot the gripping predator-prey drama constantly playing out all around you.

Since survival is something those of us at the top of our food chains tend to take for granted, it’s good that we’re reminded, now and then, of the stark reality of daily life for every other living thing with whom we share this wondrous planet.