Bass spawn either in brackish water at the heads of estuaries or in fresh rivers from late April to early May in North Carolina. Spawning occurs in May, in the Chesapeake Bay region; and perhaps in the waters of New York. Fish probably spawn June in the rivers of Massachusetts, of Maine, and of the Bay of Fundy, but in June and July in the southern shore of the Gulf of St. Lawrence and of the lower St. Lawrence River. When deposited in the water, eggs average 1.1 to1.35 mm in diameter. Within the first few hours after fertilization, however, the perviteline membrance swells to an average diameter of about 3.6 mm. Eggs hatch after 70 to 74 hours at water temperatures of 58 to 60 °C; after 48 hours at 67 °C; and after 30 hours at 71to 72 °C.
Bigelow, H.B. and W.C. Schroeder, 1953; Eschmeyer, W.N., E.S. Herald and H. Hammann, 1983; Heemstra, P.C., 1995; Robins, C.R. and G.C. Ray, 1986; Scott, W.B. and E.J. Crossman, 1973.