The Procambarus clarkii (red swamp crayfish) in Merja Zerga wetland in Morocco: Dynamic and impacts on aquatic vegetation

Procambarus clarkii, one of the most invasive aquatic species in the world, is present in the Mediterranean estuarine regions. The invasion of this species in these wetlands has a multitude of impacts, including the impact on flora. This study examines the floristic diversity and abundance of Procambarus clarkii in this wetland, as well as whether the presence of this aquatic species affects the flora. The Procambarus clarkii sampling lasted three years (2016, 2017, 2018) in the Merja zerga wetland, using fishermen’s boats. Vegetation sampling was conducted during the same Procambarus clarkii capture period to assess the abundance of Procambarus clarkii at the same time and recover the effect of this aquatic species on the flora. To strengthen our study a survey was conducted among sinners to assess the impacts of Procambarus clarkii in its living environment. The results showed that there was a significant difference in the abundance of Procambarus clarkii sampled over the years (2016, 2017, 2018). The floristic diversity of the Merja zerga lagoon is very important. The effect of Procambarus clarkii on the flora was very remarkable. Thus, the floristic species exposed to this impact are the species of genus Potamogéton. These results show that Procambarus clarkii can be considered as a factor contributing to the decline of the floristic diversity of the aquatic areas where it lives.