Preliminary Results from a New Post-Larval Fish Attracting Device in Freshwater Lakes

The live capture of coastal marine fish larvae is a critical step for studying the early life stages of fish and to better understand populations and community dynamics. Although a variety of methods have been used to capture live fish larvae in marine environments, very few innovative techniques have been deployed, tested and validated in freshwaters. This is despite the fact that new capture methods could potentially provide new insights into our understanding of fish ecology, notably in lentic environments.  

For the past 15 years, innovative light traps (CARE-Collect by Artificial Reef Eco-friendly) technique, based on the phototropism and thigmotropism of post-larvae at settlement stage, have been widely and successfully used to capture and study coastal marine fish larvae. In the present study, the efficiency of CARE light traps to monitor the abundance and population structure of native and non-native freshwater fish was tested in lakes located in South France.

The ultimate aim of the study is to test the CARE traps in a realistic context to determine its reliability as a new bio-indication tool to help managers to better understand the dynamics and structuring factors of lentic fish communities and its potential use in the monitoring of restoration projects.