**Expected Shifts in Nekton Community Following Salinity Reduction: Insights into Restoration and Management of Transitional Water Habitats**

### **Luca Scapin 1,\*, Matteo Zucchetta 1, Andrea Bonometto 2, Alessandra Feola 2, Rossella Boscolo Brusà 2, Adriano Sfriso 1 and Piero Franzoi 1**


Received: 20 May 2019; Accepted: 25 June 2019; Published: 29 June 2019

**Abstract:** A restoration project is planned to take place in the northern Venice lagoon (northern Adriatic Sea, Italy), aiming at introducing freshwater into a confined shallow water lagoon area and recreating transitional water habitats. This work describes the shifts in the nekton (fish and decapods) community structure to be expected following the future salinity decrease in the restoration area. Nekton was sampled at a series of natural shallow water sites located along salinity gradients in the Venice lagoon. A multivariate GLM approach was followed in order to predict species biomass under the salinity and environmental conditions expected after restoration. Biomass of commercially important species, as well as species of conservation interest, is predicted to increase following salinity reduction and habitat changes. From a functional perspective, an increase in biomass of hyperbenthivores-zooplanctivores, hyperbenthivores-piscivores and detritivores is also expected. This study emphasises the e fficacy of a predictive approach for both ecological restoration and ecosystem managemen<sup>t</sup> in transitional waters. By providing scenarios of community structure, the outcomes of this work could be employed in future evaluations of restoration success in the Venice lagoon, as well as to develop managemen<sup>t</sup> tools to forecast the e ffects of alterations of salinity regimes in coastal lagoons due to climate change.

**Keywords:** nekton; transitional waters; restoration; salinity; predictive models
