• Family: Cyprinidae (minnows and carps)
• Other Names: None
• Ohio Status: Threatened
• Adult Size: Typically 2.5-3.5 inches, can reach 4.5 inches.
• Typical Foods: Flying insects and various aquatic invertebrates.
The rosyside dace is a strikingly colored fish that has sides flushed with red or pink. This bright coloration covering the lower half of the fish extends from just behind the eye to beyond the front edge of the anal fin, sometimes to the base of the tail, is light red or pink on non-breeding fish and bright carmine red on breeding males. Unlike most minnow species the bright color is only slightly less intense on breeding females. Above the red or pink sides is a thin gold line which runs from the eye to the base of the tail. Above the gold line the back is dark olive brown to deep green. The fins have no spots or other distinct markings. Rosyside dace are not as long and narrow bodied, have larger more visible scales, and a smaller eye and mouth, than the closely related redside dace. Additionally the red on the sides of a rosyside dace covers the entire lower half of the sides with out a distinctive edge before reaching the belly like the red band on a redside dace.
Habitat and Habits
The rosyside dace is an indicator of very high quality small streams. This species is intolerant of turbidity and silt. They are attracted to deep pools with an abundance of woody debris. The small streams they are found in typically have rather high gradients, very clear cool water, and are in primarily forested watersheds. This species is found only in a few streams in south central Ohio both to the east and west of Portsmouth and the lower end of the Scioto River.
Reproduction and Care of the Young
Rosyside dace spawn in groups in late April or early May. Like many smaller minnows species they usually spawn in the nest of larger minnows or suckers such as creek chub, striped shiners, and common white suckers. These nests are found just above or just below fast riffles in course sand or fine gravel. They leave the eggs to be guarded by the larger species and provide no parental care.