While investigating a creek in Ohio, I turned up a few of these small, but colorful fish. Rainbow Darters only grow to be about 3 inches long. They can be a very brightly-colored creatures, depending on their sex and whether it is breeding season.
Females have brown stripes, while males usually have blue stripes that are separated by orange coloring. The first dorsal fins usually have red coloring close to the body, with a blue fringe. However, in female rainbow darters, this coloring is not very well developed and may simply appear as thin lines.
Rainbow Darters inhabit small rivers and streams in eastern North America. They have been widely located in vast numbers in the Ohio River Valley and the tributaries of the Great Lakes. They are also found throughout the Mississippi River, as far north as Minnesota and as far south as southeastern Louisiana.
This species prefers the fast-moving currents of shallow riffles in creeks and small rivers. They also have a preference for gravel or rocky-bottom streams. Typically adult fish are found in faster and deeper running waters, while younger rainbow darters are more common in slower, shallower areas and pools.
Rainbow Darters are considered shy and stay hidden for most the day between or along rocks unless they are looking for food or reproducing. They feed on a variety of aquatic insect larvae, small snails, and crayfish. They also feed on various fish eggs, typically either minnow or lamprey eggs.
It was great to be able to capture a few of these cool creatures while out in the field.