Blacknose Dace - Rhinichthys atratulus
Life history and habitat requirements: This native minnow prefers small headwater streams with moderate to rapid water with a preference for swift water. The minnow predominates in riffles, but also in shade pools along cut banks with overhanging vegetation. The blacknose dace is most frequently captured over substrates of gravel, sand rubble and silt in clear and slightly turbid water. The minnows spawn over gravel. (Sources: Fishes of Wisconsin, A Distribution Atlas of Kentucky Fishes.)
Total length: usually less than 3 inches (Hartel reports one 4-inch fish)
Pollution tolerance (US EPA): Tolerant
Classification: Fluvial Specialist
Number of fish found during 1954 & 2001 Fish Surveys:*
| Location | No. of Fish 1954 | No. of Fish 2001 |
| Assabet River | 74 | |
| Cold Harbor Brook | 37 | |
| Great Brook | 2 | |
| Hop Brook | 50 | |
| Howard Brook | 77 | |
| North Brook | 99 | |
| Total | 77 | 262 |
*Sources:
DFW. 2001. Assabet Watershed Fish Survey. Mass. Division of Fisheries and Wildlife (MassWildlife), Westborough, MA.
Schlotterbeck, L.C. and W.A. Tompkins. 1954. "A Fisheries Investigation of the Merrimack and Ipswich River Drainages." Bureau of Wildlife Research and Management, Mass. Division of Fisheries and Wildlife, Westborough, MA.
