Responses of Lake Whitefish (Coregonus clupeaformis) to Fertilization of Lake 226, the Experimental Lakes Area

Abstract

The responses of an unexploited population of lake whitefish (Coregonus clupeaformis) to fertilization of Lake 226 (L226), the Experimental Lakes Area, northwestern Ontario, were measured for 4 yr (1973–77). A vinyl sea curtain separated the lake into a northeast (NE) basin, which received P, N, and C additions, and a southwest (SW) basin, which received only N and C additions. Lake whitefish in the NE basin grew faster, had higher coefficients of condition, and had greater recruitment and production than those in the SW basin during the 2nd through 4th yr of fertilization. No differences between basins were detected in annual survival for fish [Formula: see text], but survival of age 0 fish was greater in the NE basin. Whitefish production in L226NE averaged twice that in L226SW from the 2nd to the 4th yr of fertilization, though significant variations occurred between years in both the NE and SW populations.