Prairie rattlesnake

A dry, papery buzz comes out of the grass before you see anything at all, and every boot on the trail stops mid-step. Somewhere close, coiled low and colored almost exactly like the dirt and dead grass around it, a prairie rattlesnake is telling you to back up. At Theodore Roosevelt’s badlands ranch in the 1880s, he wrote that they were “only too plentiful everywhere — along the river bottoms, in the broken, hilly ground, and on the prairies.” They’re harder to find in that same country now, but at Theodore Roosevelt, Yellowstone, Badlands, and Wind Cave, this is still the one snake in the park that can actually hurt you.

The rattle itself is not what most people think. A rattlesnake is born with a single solid button on the tip of its tail and can’t make a sound with it at all — not until after its very first shed of skin. Every shed after that loosens a new hollow segment onto the base, so the rattle grows the way a tree grows rings, one piece added at a time as the snake gets older. Except the oldest segments dry out, crack, and break off long before you’d think to count them, which means the buzz you hear is no guide at all to how big or how old the snake actually is. Long rattle or short, the warning means the same thing.

It would almost always rather buzz and retreat than fight. It has more reason to fear a hiker’s boot than the other way around. Look before you step over a rock or reach into a crevice, give the sound room, and it goes back to being just another shape in the grass.