Bluegill - Lepomis macrochirus

Habitat requirements and life history: The bluegill was introduced to Massachusetts from its original range, which extended from western New York South to Florida and west to the Rockies. It was widely stocked during the first half of the 19th century and is now common except on Cape Cod. Bluegills prefer lakes, ponds and slow-moving rivers that are warm, quiet, shallow, and weedy. Blue gills tend to overpopulate the waters in which they live, leading to stunted growth rates and large populations of small fish. They feed primarily on insects, but will also eat crustaceans, fish eggs, very small fish and aquatic vegetation. Bluegills feed most actively when water temperatures reach 81° F. Like all sunfish, the bluegill breed in the spring in shallow, saucer-shaped nests scooped out by the males. They usually concentrate their nests in colonies. Then males round up one or more females and bring them to the nest to lay eggs. After the male fertilizes the eggs, he drives off the female and fans the eggs with his tail until they hatch. He will stay to protect the young until they can fend for themselves. (Sources: Massachusetts Wildlife, No. 2, 2000, Special Fishing Issue and AMC Guide to Freshwater Fishing in New England)

Total length: 5-7 inches (some populations up to 12 inches).
Pollution tolerance (US EPA): Tolerant
Classification: Macrohabitat generalist

Number of fish found during 1954 & 2001 Fish Surveys:*

Location No. of Fish 1954 No. of Fish 2001
Assabet River 396 325
Assabet Brook   15
Cold Harbor Brook 1 7
Danforth Brook   2
Fort Meadow Brook 1  
Hop Brook   1
Nashoba Brook 41 4
North Brook 12  
Spencer Brook 76  
Stirrup Brook 92  
Total 619 354

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.