Spatiotemporal Dynamics of Mediterranean Shallow Coastal Fish Communities along a Gradient of Marine Protection

Abstract

The importance of habitat factors in designing marine reserves and evaluating their performance over time has been regularly documented. Over three biennial sampling periods, we examined the effects of vegetated coverage and habitat diversity (i.e., patchiness) on fish density, community composition, and species-specific patterns along a gradient of protection from harvest in the shallow Spanish southern Mediterranean, including portions of the Tabarca marine reserve. With the exception of two herbivores (Sarpa salpa and Symphodus tinca), vegetated cover did not significantly affect fish densities, while habitat diversity was an influential factor across all three sampling periods. Overall, fish density was more positively associated with more continuous vegetated or unvegetated habitats, and was greatest in areas of highest protection (Tabarca II – Isla Nao site). These patterns were usually observed for four abundant fish species (Boops boops, Chromis chromis, Oblada melanura, and S. salpa). Fish community composition was distinct in the most protected portion of the Tabarca reserve, where it was also most stable. Our findings align with previous investigations of the Tabarca reserve and its surrounding areas, and demonstrate its continued effectiveness in conserving fish biomass and habitat. Together with effective management, marine reserves can facilitate greater species abundance, more stable biological communities, and resilient ecosystems.

Seasonal variation in the metabolome expression of Jania rubens (Rhodophyta) reveals eicosapentaenoic acid as a potential anticancer metabolite

“…For example, some herbivores will be more abundant during certain seasons and some epiphytes might proliferate in the same manner. As J. rubens grows year-round, it faces many forms of grazing by fish, mollusks and crustacea, as well as the competition that rises due to seasonal dynamics of epiphyte algae and microbial settlements 32 , 33 . Considering that, our findings strengthen the assumption that seasonal variation can have a major impact on the chemical profile and bioactivity of the collected seaweed and therefore should be considered when one attempts to explore natural compounds with biological effects.…”

An Experimental Investigation of Turbulence Features Induced by Typical Artificial M-Shaped Unit Reefs

“…Different configurations can in fact influence the flows passing through these structures, generating specific currents that could aid the deposition of solid material as well as the exchange of nutrients between multiple layers, with a consequent beneficial aspect for fish expansion [19,20]. Furthermore, these structures may also be used as protection or gathering areas by fish or other organisms, because the gentle and stable eddy currents created on the back of them could support the deposition of nutrients and function as a shield that is useful for avoiding enemies or larger predators [21][22][23][24][25][26][27].…”