Monitoring of the water temperature at the Wolfgangsee lake outlet

Due to climate change, it has been proven that surface waters are becoming increasingly warm. The uppermost layers of the lakes are particularly affected here, as they have warmed significantly above average in recent years due to rising summer temperatures. However, an increase in water temperatures in these large stagnant bodies of water can become a habitat-limiting factor, especially for river systems if they drain large proportions of the flow from the layers near the surface in the area of ​​the lake's outflow. Due to the topographical and hydrological conditions, this most likely occurs in the Wolfgangsee - Ischler Ache connection system. This means that in the Ischler Ache there is a hybrid form of water for the aquatic cenosis in general, but for the fish ecology in particular, which makes sustainable population build-up or sustainable fishery management in the sense of classification as a fish region more difficult. On the one hand, due to the changing solids management in the catchment area, the Ischler Ache has a high redistribution dynamic, thus alpine wild river characteristics, and on the other hand, due to the increased water temperatures, these habitat conditions are shifted towards “potamal”. Both developments together only provide usable habitat conditions for a few species. The aim of the research project should be to examine the variable water temperature conditions in the area of ​​the Wolfgangsee outflow in detail. By examining temperature stratification, the possibilities for extracting deep water from the lake should be examined in order to specifically supply the Ischler Ache with cooler water at certain times (heat periods in summer). Data should be collected over a period of two years in order to achieve initial certainty in management's forecast.