Migration and life history alternatives in a high latitude species, the broad whitefish, Coregonus nasus Pallas

Abstract

Abstract – We examined the expected changes in the life history trajectory of an Arctic species, broad whitefish, in the lower Mackenzie River between an anadromous population with spawning migrations of 350–450 km and a potamodromous population with spawning migrations of 5–12 km. Based on life history theory we predicted that the anadromous population would have faster growth, later age‐at‐maturity, and greater reproductive investment than the potamodromous population. Early in its life the anadromous population had faster growth than the potamodromous but later growth was slower. Age‐at‐maturity was greater in the anadromous population than the potamodromous. Reproductive investment was higher in the anadromous population. We conclude that the broad whitefish did not conclusively follow the pattern of variation observed between migratory and relatively sedentary populations in temperate zones. Fecundity was greater in the migratory population but not conclusively linked to age‐at‐maturity or growth‐rate differences.