Earth Almanac: May/June 2005

Streambed Jewels

Sometimes the most beautiful things in nature go unseen, and therefore unappreciated and unprotected. Such is the case with darters—pinky-size fish native to most of North America. Of about 150 species in three genera, none is more colorful than the rainbow darter. In spring, from Minnesota to Ontario and south to Alabama and Arkansas, males are in full spawning garb. Ease up to a warm, clear, gravel-bottomed stream and you'll see them glowing with impossible shades of green, blue, yellow, red, and orange, and hugging the bottom because they lack the well-developed swim bladders of their larger cousins—the walleye, sauger, and yellow perch. When a female selects a spawning site, she'll burrow into the gravel, where she'll be mounted by a male. No one fishes for darters, so no one speaks for them when their habitat is destroyed by dams, urban and agricultural runoff, mining subsidence, and channelization.