ACTION D.1 MONITORING OF THE ERADICATION AND SALVAGE ACTIONS IN HIGH ALTITUDE LAKE ECOSYSTEMS

In many cases, the presence of non-native fish in high-altitude alpine lakes represents an ecological exclusion factor for many native taxa and also affects the energy and material flow from water to land. Thanks to the Salvelinus fontinalis eradication process, a quick recovery of the natural functioning of treated ecosystems is expected, which includes the restoration of the natural wildlife, ecosystem structure and energy flow between coastal and aquatic environments.

The effectiveness of the eradication will be regularly monitored from the beginning of the project on all lakes subjected to Conservation Actions 1 and 2 (Djouan, Nero, Dres and Laynir lakes). The objective is to describe the recovery of the aquatic ecosystem during and at the end of the eradication process, i.e. from 2013 to 2015. Each of the operations listed below will be repeated twice a year in the early and mid-summer seasons to monitor both the initial and advanced development of the native communities. Biological and chemical samples will be collected during the summer months, to be analysed in winter. Monitoring actions include:

1. Monitoring the density of the fish population

2. Monitoring via bioindicators: monitoring data will be compared to those collected between 2006 and 2011 making it possible to assess the resilience of treated ecosystems.

3. The effect of fish eradication on the chemico-physical characteristics and trophism of lakes will be assessed collecting water samples integrated on the water column in the deepest point of each lake. The limnological characterisation of lakes will also be integrated with temperature and dissolved oxygen profiles using an immersion multi-parameter probe.