Zonation of a lentic ecotone and its correspondence to life history strategies in fish

A drainage channel network southeast of lake Neusiedl was investigated for fish species distribution. The network consists of relatively large and permanent channels providing a stable habitat for fish and smaller unstable channels drying up approximately once every five years. A consistent pattern of fish species distribution was found which could be interpreted with the help of a new triangular model of life history adaptations. In permanent channels so-called periodic and equilibrium species prevail whereas temporary channels are inhabited by opportunistic species exclusively. In the drainage channel network a number of locally endangered fish species which have disappeared from the adjacent lake during the last decades were found suggesting that the channel network functions as a refuge for these fishes.