Compared to the vast area covered by the open sea, shallow coastal environments are subjected to disproportionately higher pressures due to their dynamic interplay with the terrestrial realm and the direct effects of human activities. Many important Mediterranean rocky reef benthic communities are particularly vulnerable to anthropogenic stressors (e.g., pollution, overfishing, coastal development) and have suffered major losses and severe degradation in the recent decades. The associated rocky reef fish assemblages are also of high ecological importance, since they play a fundamental role in the functioning of reef ecosystems.

In this study shallow rocky reef fish assemblages were studied in sites of low versus high fishing pressure (FP) across the Aegean Sea, in order to assess community structure at a large scale and investigate spatial variability in relation to FP, depth, and geographic location.

The obtained results show that the N Aegean sites scored higher in number of species and biomass of carnivorous fish, whereas the S Aegean had a higher biomass of several allochthonous and thermophilous species. Abundance and biomass estimates were higher in low FP sites, and primarily at the 15 m depth zone, where low FP sites had the double abundance and 2.8 higher biomass. Biomass of carnivores was generally very low, except at deep sites of low FP.

The authors conclude that given that sites of lower FP represent areas of lower conflicting interests for fisheries whilst providing enhanced biomass levels, they should be included in future marine conservation planning schemes, as they could contribute to the replenishment of fisheries and the boosting of conservation benefits provided by MPAs, once properly managed.

https://www.frontiersin.org/articles/10.3389/fmars.2019.00599/full

Sini et al. (2019) Small-scale coastal fishing shapes the structure of shallow rocky reef fish in the Aegean Sea. Frontiers in Marine Science doi: 10.3389/fmars.2019.00599.