Except for a period of time around spawning, males and females have a similar appearance. They have a medium green/olive dorsum, which fades to white around their ventral surface. The length of their bodies may contain randomly scattered darker spots, while the fins are colorless. During the spawning season, males develop a slate-gray colored dorsum, a yellowish underside, and small dark spots on the pelvic fins. Females remain largely unchanged during this time. Average size is 18.7 cm long.
Freshwater throughout Eastern and middle United states and Canada, benthopelagic (near-bottom dwellers). Inhabit rocky riflles, runs and pools of headwaters, creeks and small to large rivers.
The male begins building a nest in late winter and continues until spawning time in spring/summer by rolling stones along the bottom of the stream with its nose- hence "stoneroller". Eggs are adhesive once fertilized and attach to gravel at the bottom of streams. At water temperatures of 21 to 25 degrees Celsius eggs hatch in 69 to 72 hours. Newly hatched fish school together in warmer, calmer backwaters and highly vegetated stream margins.
Herbivorous. Consumes detritus, algae and less commonly, small aquatic insects. May consume up to 27% of their body weight in algae per day.
Conservation of this fish is important for a wide variety of reasons, most notably because of their ability to consume a significant amount of algae. The Central Stoneroller has been shown to be able to reduce the overall algae levels in streams it inhabits due to this trait and play a large role in the composition of a waterway and their nutrients.
In this video, stonerollers can be seen schooling in groups while eating algae.
The large pointed tubercles (horn like bumps) on the head, are only present in males during the breeding season.
Stone rollers scrape the rocks, logs, and other submerged structures for algae, detritus and a variety of small organisms.