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The gobiid assemblage of the Venice Lagoon shallow waters was investigated by means of a semi-quantitative standardized sampling (using a small beach seine), stratified into five main types of shallow subtidal habitats and conducted on a seasonal basis during 1 year. The degree of overlap in resource utilization among six coexisting goby species was assessed, along both the time axis, by analysing the seasonal variation in abundance and reproductive status (as revealed by the gonado-somatic index) and the habitat axis, by comparing species abundance across different habitat types and controlling for the effects of some abiotic factors. Smaller species, and especially the marbled goby Pomatoschistus marmoratus, dominated the local assemblage. Although the cycle of shallow water colonization and seasonal variation in total abundance were basically similar, species showed differences in timing of reproduction and recruitment, as well as in habitat preference. The larger species belonging to the genera Gobius and Zosterisessor tended to overlap their habitat use, being more abundant in seagrass habitats than in the unvegetated habitats, whereas the smaller species belonging to the genera Knipowitschia and Pomatoschistus avoided seagrasses, preferring in most cases mud flats and salt marsh creeks. Within these two groups of species some further slight differences in species habitat preference, relationship with abiotic factors and reproductive ecology could be detected. Results are discussed in the light of both ecological mechanisms underlying coexistence of closely related species and the current knowledge of the phylogeny of Mediterranean gobies. # 2005 The Fisheries Society of the British Isles

Marine litter is a significant and growing pollutant in the oceans. In recent years, the number of studies and initiatives trying to assess and tackle the global threat of marine litter has grown exponentially. Most of these studies, when considering macro-litter, focus on floating or stranded litter, whereas there is less information available about marine litter on the seabed. The aim of this article is to give an overview of the current state-of-the-art methods to address the issue of seafloor macro-litter pollution. The overview includes the following topics: the monitoring of macro-litter on the seafloor, the identification of possible litter accumulation hot spots on the seafloor through numerical models, and seafloor litter management approaches (from removal protocols to recycling processes). The article briefly analyzes the different approaches to involve stakeholders, since the marine litter topic is strongly related to the societal engagement. Finally, attempting to answer to all the critical aspects highlighted in the overview, the article highlights the need of innovative multi-level solutions to induce a change toward sustainable practices, transforming a problem into a real circular economy opportunity.

The brown meagre (Sciaena umbra) is a demersal sciaenid fish recognized as indicative of good environmental quality and is defined as an umbrella species for the ecological community of rocky coastal habitats. Sciaena umbra is classified as a Vulnerable fish species by the International Union for Conservation of Nature (IUCN) and knowledge on the distribution of its spawning habitats is essential for its conservation. Passive acoustic monitoring (PAM) is a suitable tool to monitor S. umbra distribution because of the high consistency, over space and time, of the communication sounds that this species emits during the reproductive period, with irregular or regular rhythms, or with calls merging into a chorus. During the summer of 2019, the presence of this species was investigated acoustically at 40 listening points distributed along the tidal inlets that connect the Venice lagoon with the open sea. Longer sounds, comprising a higher number of faster repeated pulses, were found during the chorus and were used as a proxy of spawning activity; similar sound features have been recorded in different captive Sciaenids during spawning. The three inlets were classified as more or less suitable for spawning on the basis of the vocal rhythms identified, demonstrating a clear preference along a north–south gradient and indicating higher spawning activity in the internal‐facing areas of the inlets, compared with the seaward‐facing areas. The chorus occurred in localized areas consistently throughout the breeding season, suggesting that spawning is concentrated in preferred areas. For the first time a relationship between the sound features and vocal rhythms of fish has been highlighted by an in situ study. This validates the use of the chorus as a reliable natural indicator of S. umbra breeding sites, and in turn suggests a potential non‐invasive approach based on PAM for mapping the key reproductive areas of this vulnerable species in the Mediterranean Sea.