Shutterstock/Travis Potter
A largemouth bass hovered in front of me, tail angled toward the surface and head tipped down facing the rocks, so intent on something below that it seemed entirely unperturbed by the three divers who had drifted into its space.
This was my first open-water dive. Oregon’s murky Woahink Lake presented just 6 feet of visibility, with silt clouding even that, and I wore exposure protection so thick I wasn’t sure how I was supposed to breathe, let alone fin.
I’d been focused on one thing—staying calm—until that fish made me forget myself and start wondering what, exactly, it was doing.
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The bass held its position with tiny adjustments: tail rocking, fins paddling just enough to keep it suspended. The intensity of its gaze and the very specific position it held in the water column left no doubt in my mind that it was watching something or waiting for something.
Our instructor eased forward and shifted a rock below the bass, just enough for us to see beneath. A small brown crayfish peered out, pincers raised in a defensive posture, antennae quivering frantically as though to say, “Shoo. Leave me alone. Go away!”
The bass darted in. It missed, and the impact stirred a bloom of silt that swallowed the crayfish as it skittered backward under another rock. The fish kept searching for it, nosing through the mud, certain it must be there.
Taking a Closer Look at the Critters You Dive With
As we picked over the rocks looking for other small critters, the bass followed along. Every now and then, it slipped into that same tail-up, head-down posture, and I began to wonder if our presence was part of the equation. Was this signal directed at us? Was the fish communicating, attempting to point out a possible target? Were we supposed to answer this signal by flushing prey?
When I climbed out of the water, I was barely able to contain my excitement. I wanted to understand what I’d just seen.
And that question—what am I actually watching?—is the reason for this new column. It’s one I’ve found myself asking time and time again after observing a peculiar behavior—a starry flounder curiously watching me vacuum its aquarium exhibit, fish chasing a laser dot created by my torch, a wolf eel affectionately leaning in for a chin tickle from a familiar diver.
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In “the Little-Known Reef,” I’ll explore animal behaviors divers are uniquely positioned to witness—small, strange moments that hint at bigger inner lives. Each installment will focus on one behavior you can look for on your own dives, including what it might mean, what research suggests so far and what’s still uncertain. I’ll also speak with the scientists who study these questions, translating the jargon into something clear, useful and fun.
Despite decades of research, we’re still just beginning to understand how marine animals perceive, learn, communicate and make decisions. Divers get front-row seats to that unknown and are often at the forefront of making it known.
My hope is that this column inspires you to take a closer look at the critters you dive with, to notice patterns, capture observations and ask questions. Because if there’s one thing diving has taught me, it’s that we really don’t know what a fish knows. And some of what we do know is because an ordinary diver like you took note of something they found interesting.
