After a very dry summer, rains have started to fill up part of the rivers we are studying. In some cases this has led refuge pools to connect with previously dried-up sections of river, as has happened in the Riera de Escales in the photo, a very dry stream in the Garrotxa. Interestingly enough, a day or so after the rain the pools have disconnected again, and we found fish in the newly created pools, meaning they must have come from the bigger original pool. How they got there, e.g. passive by strong flow of the rain or by actively swimming, is something to be determined, but interestingly it only seems to be fish of certain size-classes. These fish may be safe for now in their new pool, but if it does not rain enough in the coming weeks, the pool may still dry up and the fish will die
#drought #freshwater #freshwaterecology #riuscatalans #sequera #aigua
9 months ago