Alessandro Rinaldi

Subadult flathead grey mullets (Mugil cephalus) were fed three experimental diets containing increasing percentages of partially defatted black soldier fly (Hermetia illucens, BSF) that proportionally replaced the protein sources in the reference diet. At the end of the feeding trial, fish growth and gut, liver and spleen histology were evaluated. BSF inclusion did not significantly affect growth performances in any dietary groups. However, Fulton’s condition factor was lower in fish who were fed diets with the highest replacement levels (15% and 20%; BSF15 and BSF20) compared to those fed the 10% replacement (BSF10) and the control diet (BSF0). Histological analyses revealed increased villi thickness and mucous cell proliferation in the intestine of fish from BSF10 and BSF15 groups. A significant worsening of intestinal condition was observed in fish from the BSF20 group. Liver histology was not affected, while a dose-dependent effect on spleen was observed in fish fed BSF inclusions. Despite the absence of enteritis signs, an increase in macrophages/like TNF-α+ cells in the intestine mucosa indicated immune stimulation in the BSF10 group. Results indicate, for the first time, a threshold for BSF meal inclusion in diets specifically formulated for flathead grey mullets. The BSF10 diet was optimal, as growth performance was not affected and intestine health improved at both morphological and innate immune system levels.

Addressing the challenges posed by Non-Indigenous Species (NIS) demands coordinated efforts across terrestrial, freshwater and marine ecosystems. In this study, we engaged a diverse group of 90 Italian researchers operating within these three domains to identify and assess strategies for advancing NIS research, using a structured, interactive and expert-driven methodology. The process began with a comprehensive evaluation of ongoing activities, research methodologies and specific needs. This assessment provided information for the development of an initial set of suggestions to ameliorate NIS research, which were collectively discussed and refined, leading to the identification of six good practices identified by the acronym TRACKS and described as: i ) Tracking NIS in biodiversity data collection; ii ) Reference protocols for NIS data collection; iii ) Active participation; iv ) Collaboration and FAIR principles; v ) Knowledge hub for NIS data; vi ) Strategic communication. A SWOT framework was then applied to analyse the internal and external factors influencing the Strengths, Weaknesses, Opportunities and Threats associated with each good practice. Consensus-building techniques were used throughout the evaluation process to ensure the robustness of outcomes. Finally, a quantitative assessment of the SWOT analysis revealed a strong consensus amongst experts regarding the various strengths, weaknesses, opportunities and threats of the different good practices, along with a general optimism about the opportunities and strengths associated with their implementation. Developed within the Italian research community, this approach offered valuable insights to researchers worldwide working on NIS and enabled the expert assessment of six best practices that may serve as a benchmark for advancing the science of biological invasions.

Addressing the challenges posed by Non Indigenous Species (NIS) demands coordinated efforts across terrestrial, freshwater, and marine ecosystems. In this study, we used the Italian research network as a case study to identify and evaluate measures designed to enhance NIS research through a structured, interactive, and expert-driven strategy. The process began with a comprehensive evaluation of ongoing activities, research methodologies, and specific needs. This assessment informed the development of an initial set of proposals, which were collectively discussed and refined, leading to the identification of six good practices identified by the acronym TRACKS and described as: i) Tracking NIS in data collections; ii) Reference protocols for NIS data collection; iii) Active participation through citizen science and local ecological knowledge; iv) Collaboration in data sharing according to the FAIR principles; v) Knowledge Hub as centralized data repository for NIS data; vi) Strategic communication to raise public awareness and support public engagement. A SWOT framework was then applied to analyze the internal and external factors influencing the Strengths, Weaknesses, Opportunities, and Threats associated with each practice. Consensus-building techniques were used throughout the evaluation process to ensure the robustness of outcomes. Finally, a quantitative assessment of the SWOT analysis was conducted with 90 NIS experts working in terrestrial, marine, and freshwater ecosystems. This approach provided valuable insights into differing perceptions and enabled a clear presentation of six good practices to be consistently applied across NIS research systems.

Ocean warming poses significant threats to coastal ecosystems. This study investigates the impact of thermal effluents from power plants, as proxies for climate-driven temperatures increase, on Posidonia oceanica meadows and associated fish communities. Using a gradient-based approach, we analyzed environmental variables, seagrass indicators, fish assemblages, and functional group (FG) dynamics across a thermal gradient extending from the effluent outfall itself. Results indicate that temperature is the dominant factor influencing P. oceanica, with reduced leaf length, shoot density, and rhizome weight characterizing samples closest to the effluent. Despite compensatory mechanisms, the overall photosynthetic biomass and resilience declined under thermal stress. Fish assemblages exhibited reduced species richness and biodiversity close to the thermal effluent, with opportunistic and thermophilic species dominating. An FG analysis revealed disrupted seasonal patterns, shifts in trophic dynamics, and functional compensation among species, highlighting potential ecological imbalances. Notably, transient predators thrived near the effluent, while more sedentary and temperate species were displaced. These findings underscore the cascading effects of rising temperatures on coastal habitats such as P. oceanica meadows and their associated communities, emphasizing the urgency for conservation measures. By identifying critical thresholds and adaptive responses, this study contributes valuable insights into the consequences of localized impacts of thermal stress on coastal biodiversity and ecosystem services.

Rising sea temperatures, driven by climate change, pose significant threats to coastal ecosystems. This study investigates the impact of thermal effluents from power plants, as proxies for climate-driven temperature increases, on Posidonia oceanica meadows and associated fish communities. Using a gradient-based approach, we analyzed environmental variables, seagrass indicators, fish assemblages, and functional group (FG) dynamics across a thermal gradient extending from the effluent outfall itself. Results indicate that temperature is the dominant factor influencing P. oceanica, with reduced leaf length, shoot density, and rhizome weight characterising samples closest to the effluent. Despite compensatory mechanisms, the overall photosynthetic biomass and resilience declined under thermal stress. Fish assemblages exhibited reduced species richness and biodiversity close to the thermal effluent, with opportunistic and thermophilic species dominating. FG analysis revealed disrupted seasonal patterns, shifts in trophic dynamics, and functional compensation among species, highlighting potential ecological imbalances. Notably, transient predators thrived near the effluent, while more sedentary and temperate species were displaced. These findings underscore the cascading effects of rising temperatures on coastal habitats such as P. oceanica meadows and on their associated communities, emphasizing the urgency for conservation measures. By identifying critical thresholds and adaptive responses, this study contributes valuable insights into the consequences of localized impacts of thermal stress on coastal biodiversity and ecosystem services.