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)