Influences of human activity and climate on the stock‐recruitment dynamics of whitefish, <i>Coregonus lavaretus,</i> in Lake Geneva

Abstract

Abstract Analysis of long‐term catches from the deep peri‐alpine Lake Geneva, showed a shift in the stock‐recruitment relationship of Coregonus lavaretus (L.), a target species of commercial fishing. This change was mainly related to large‐scale meteorological factors. Higher spring water temperatures may have improved larval survival and hence recruitment of whitefish via: (1) a better match between the hatching date of whitefish larvae and development of their zooplankton prey; and (2) the positive temperature effect on larval growth. In Lake Geneva, changes in regulatory mechanisms coupled with stocking and improved water‐quality have led to an explosion in the C. lavaretus population in recent years. These results highlight the relevance of long‐term changes in the stock‐recruitment relationship for management of aquatic ecosystems that are sensitive to climate forcing.