As winter faded into spring and the last remnants of snow remained in shadowy patches atop higher peaks, I wandered into the Rattlesnake Wilderness, outside of Missoula, Montana. The air was filled with male songbirds singing to attract a mate for the season. The crackling call of the corvid, the rasp of the chickadee, and the delicate honk of the red-breasted nuthatch were giving way to the springtime calls of warblers and thrushes.