Trout are such jerks. I love them, but they’re jerks. Just look at that big one, finning silently against the gentle current in this cool mountain brook, its mouth wordlessly opening and closing and completely refusing to take the fly I’ve lovingly presented in a miraculous roll cast, like easily the best cast of my life, right into that dark hole where I can see the son of a gun, and it’s not so much as casting a sideways glance at the Elk Hair Caddis, and damn it I didn’t hike all the way out here for nothing, and look, I’m not above taking out my spinning rod and tossing a Kastmaster at it just to see what happens, but that’s back at the truck, why did I leave it at the truck? And look, now the big brown’s spooked and just darted under that tangle of branches leaning over the water, and now it’s sure as hell not gonna take any flies or even lures for that matter anymore.

See? Total jerk. God, I love them.

Anyway, it’s known to science that any trout is far smarter and more knowledgeable than any human who has ever lived, so let’s even the balance a little with some interesting trout facts.

Their scales grow rings just like a tree

As trout grow, new tissue is added around the edges of their scales. These persist as the fish age, and the scale’s rings can be read just like the rings on the inside of tree trunks, giving you some idea of how long that trout’s been swimming around, inspiring and frustrating anglers.


Brown trout are far more genetically diverse than we’ll ever be

There are more genetic variations among British brown trout alone than there are between the varied populations of all humans on the globe. I’m no geneticist, but this probably has to do with the fact that brown trout have nearly twice as many pairs of chromosomes (about 40) than humans do (23). These fish seem to have an unusual ability to rapidly evolve adjustments to water temps, food sources, the colors of a river, among lots of other things.

Trout have learned from chameleons how to change their color

Okay, they probably didn’t really learn this from chameleons, but trout are known to be able to change their color in response to outside stimulus or to blend in with the background. This makes them harder to spot in darker streams, and therefore, of course, makes them much harder to catch, but it also makes them little fish wizards.

People have been writing (and probably complaining) about trout fishing for 2,000 years

It’s often noted that Romans had written about Macedonians fishing for “speckled fish” —trout, most likely—as early as the year 200 AD. But back in 1921, William Radcliffe quoted in his book Fishing From the Earliest Times, a Roman poet named Martial who wrote sometime near 10 AD, this very anglery-sounding line: “Who has not seen the scarus rise, decoyed and killed by fraudful flies?” Fraudful flies, eh?  Decoyed, you say? I’d say those scaruses (lord knows what sort of fish that poet was describing, but scarus is now the name of a genus of parrotfish) were being angled, all right.

The earliest known “how-to” fly-fishing text was jotted down six centuries ago in a German prayer book

The Haslinger Breviary, a 15th century book of Roman Catholic prayers and hymns, was owned by an Austrian priest named Leonardus Haslinger. He was apparently quite taken with fly fishing. The back of the book contains a handful of pages on which Haslinger penned trout fishing advice and fly-tying techniques and patterns sometime around 1460. This predates the well-known “Treatyse of Fysshynge wyth an Angle” by nearly 40 years. It’s also a telling that a priest would find his thoughts wandering from prayer to fishing so easily. We’ve all been there, father.


Adventure Journal relies on reader support. Please subscribe to our amazing printed quarterly or pick up an issue here.