The slender-headed darter was taken at all stations but was more abundant in the Neosho than in the Marais des Cygnes. The lower Marais des Cygnes, however, was the only station with a relatively large population in 1957. Slender-headed darters were rare in the Neosho River in 1957 and did not become common until 1959.
The largest population was found at the upper Neosho station in 1959. This darter occurs most frequently in swift water over gravel bottom, but was taken in various habitats, including an intermittent pool at the upper Neosho station on 7 September, 1957.
At the middle and lower Neosho stations, considerably greater numbers were taken in June, July, and early August than in May or late August. The abundance in my collections diminished from a peak in early July, to scarcity in late August.
Young-of-the-year were taken at the lower Neosho station on 1 July, 1959 (and subsequently), in moderately fast water over gravel. On 21 August, 1958, a ripe female (eggs stripped easily) was the only slender-headed darter present in a collection from riffles at the middle Neosho station.
Percina caprodes (Rafinesque)
Logperch
Logperch were not taken in the Marais des Cygnes. They were rare in the Neosho, where they were taken most frequently at the upper station in water two to three feet deep, over gravel bottom, in moderate to slight current. This species was present in intermittent pools at the upper Neosho station in 1957.
Percina copelandi (Jordan)
Channel Darter
One specimen was taken at the lower Neosho station in 1959. Because no others ever have been found in the mainstream of the Neosho River, I suspect that my specimen is a "stray" from one of the smaller tributaries, where channel darters are locally common.
Etheostoma flabellare Rafinesque
Fan-tailed Darter
The fan-tailed darter is represented in my collections by one specimen, obtained in the mainstream of the Neosho River at the lower station in 1957. Records of this species in Kansas are almost confined to the smallest, clear, permanent streams of the southeastern part of the state. My specimen may represent a small population that retreated to the mainstream of the Neosho during drought.