The hyperiid amphipod Brachyscelus rapacoides is a warm-water species associated with gelatinous zooplankton. In the Mediterranean it has been reported in association with Rhopilema nomadica in both Israel and Turkey. Here, we document the first record of B. rapacoides in Greek waters, representing the first confirmed record for Europe, based on both morphological examination and DNA barcoding of the mitochondrial COI gene. Specimens were collected from the umbrella of infested R. nomadica from two localities in the southeastern Aegean Sea. Diagnostic morphological characters, particularly the dentition of gnathopods 1–2 and male antennal morphology, agree with published redescriptions of the species. Phylogenetic analyses placed the studied specimens within B. rapacoides, clearly separated from congeners. This finding extends the known distribution of the species westwards in the Mediterranean and further supports its close ecological association with R. nomadica. The record highlights the role of gelatinous hosts in facilitating dispersal of symbiotic hyperiids and underscores the importance of integrating molecular tools and citizen science observations for early detection of overlooked pelagic associates.
Urban rivers receiving multiple wastewater inputs require reliable diagnostic tools to disentangle overlapping nitrogen sources. Here, we investigate wastewater source attribution in a densely urbanized basin using isotopic tracers together with diagnostic indicators based on contaminants of emerging concern (CECs), rather than CEC occurrence alone. Monthly water sampling over 2 years at five stations in an urban river system included nitrate isotopes, conventional hydrochemistry, and a broad suite of CECs. Nitrate concentrations reached up to 18.3 mg L-1 as NO3--N, and δ15N-NO3- values ranged from +6.1 ‰ to +24.2 ‰, consistent with variations in total nitrogen loads along the river continuum. Although isotope signals indicated increasing wastewater influence downstream, isotopic information alone was insufficient to distinguish between human and animal derived wastewater sources. The integration of nitrate isotopes with CEC-derived diagnostic indices, including the Human Wastewater Index (HWI) and the Hospital Index (HI), within a Bayesian mixing framework based on characterized source signatures revealed that human wastewater contributions exceeded 60 % at all monitoring stations. Elevated HI values further indicated hospital wastewater inputs that were not detectable using isotopic variables alone. An ecological risk assessment indicated that, in 70 % of the samples, the combined risk from detected CECs was high, with over half of the individual compounds present at concentrations exceeding their respective acute toxicity thresholds. These results demonstrate that CEC-based diagnostic indicators provide complementary information to isotopic tracers and substantially improve wastewater source attribution in complex urban river systems, with direct implications for monitoring and management of urban water quality.
Coastal lagoons are highly vulnerable to human and climatic pressures, yet long-term ecological changes remain poorly quantified. We analyzed four decades (1980–2020) of data from fisheries from six lagoons in the Amvrakikos Gulf, Greece, using ecological indicators to assess trophic structure, exploitation status, and ecosystem responses. Cluster analysis of species level fishery production revealed a distinct temporal regime shift in the late 1990s–early 2000s, reflecting a major reorganization of species contributions to total yield. Mean total yield (Y), showed a consistent declining trend across lagoons, ranging from 2.7 ± 2.0 to 7.2 ± 5.0 t km−2. Primary Production Required (PPR) declined (0.8–1.5 × 1010g C km−2 yr−1), while Mean Temperature of the Catch (MTC) increased in five lagoons (19.0–21.4 °C) and remained stable in one (20.0 ± 0.9 °C). Pelagic to demersal (P/D) ratios generally decreased (0.09–1.26), and Q-90 values were variable (0.8–2.2), highlighting site specific ecological dynamics. Short term yield predictions for 2021–2025 ranged from 0.78 to 6.75 t km−2, remaining comparable to recent historical levels, while the estimated carrying capacities varied from 1.79 to 9.11 t km−2, reflecting contrasting exploitation states among lagoons. These results demonstrate that multi-indicator, fishery-based analyses provide a robust framework for quantifying ecological change and guiding adaptive management in lagoon ecosystems.
This study presents a 1:150,000 scale geomorphological map of the Gulf of Corinth (central Greece), integrating terrestrial and submarine landforms. The Gulf, an asymmetric WNW-ESE half-graben, is one of the tectonically most active areas in the eastern Mediterranean, with an uplifting southern flank and a downward flexed northern one. A multidisciplinary approach, combining field surveys and high-resolution seafloor bathymetry, was used to map the emerged and submerged geological and geomorphological features. The southern terrestrial sector shows clear evidence of tectonic uplift, such as marine terraces, elevated Gilbert deltas, tidal notches at higher elevations, and reversed drainage features. In contrast, the northern part is notable for the absence of Quaternary marine or lacustrine sediments and displays a gently sloping shelf with submerged tidal notches, indicating ongoing tectonic subsidence. The map offers a comprehensive view of the complex geomorphology of the region, shaped by Quaternary tectonic activity.
The advent of wind farming as a renewable energy source necessitates assessment of the effects of electromagnetic fields (EMF) on fish, especially when done in conjunction with aquaculture. In this study, we investigated the effects of an EMF on the behavior of European sea bass fingerlings. A T-maze apparatus was used to record the behavior of the fish with and without the presence of a static EMF of 10 mT and subsequently, several behavioral metrics were analyzed using specialized software. Our results suggest that E. sea bass can perceive magnetic fields. Compared to the control group, fish exposed to the EMF showed reduced exploratory behavior with longer periods of immobility, traveled a shorter total distance, and exhibited freezing behavior at an increased frequency. In addition, fish showed a preference for the geomagnetic south. The findings offer valuable contributions to our understanding of EMF effects on fish, which in turn may be useful in shaping the future of fish farming in conjunction with energy production .
