Environmental drivers and vulnerability of reef fishes highlight the need for multi-habitat conservation in remote insular ecosystems.

Spatial distribution and diversity of mcyA gene-carrying cyanobacteria in planktic and benthic communities of Swiss alpine lakes.

Seafloor marine litter density and distribution in the Jordanian Gulf of Aqaba, northern Red Sea.

Are perspex panels suitable surrogates for natural hard substrates in coastal ecological studies? An example from the low-diversity Baltic Sea.

Evaluating ecological connectivity of key benthic habitats in a dynamic, complex archipelago

Dynamics and population genetics of Pinna rudis in the Tyrrhenian Sea: Exploring the potential link to the local extinction of Pinnanobilis.

Multiple ecotoxicological effects of sublethal exposures to atmospheric particulate matter in two neotropical benthic species.

Microplastics are small, purposefully inserted plastic particles less than 5 mm. Micro beads, a kind of microplastics are frequently used as inexpensive fillers in cosmetics for scouring or exfoliating. Microplastics have the ability to get past water filtration systems and into lakes, rivers and seas. In maritime environments, they build up because they are not biodegradable. Although UV filters in sunscreens shield the skin from UV rays, some of them such as oxybenzone and octinoxate can harm marine life by causing coral bleaching. Marine habitats are greatly impacted by coral reef degradation. The majority of plastic pollution in the oceans is the result of inappropriately disposed of plastic packaging, which can wind up in waterways and eventually the ocean, where it can either become microplastics or be consumed by fish and clog their digestive tracts. Aquatic life and habitats are at risk when microplastics from personal care items end up in the ocean and other bodies of water. Furthermore, some cosmetics include dangerous ingredients. They have the potential to destroy coral reefs and other aquatic life when they wash down the drains of our sinks, showers, and bathtubs. Furthermore, the fish in these waters frequently ingest the pollutants, which has detrimental effects on aquatic animals' health and scarcity. From excessive packaging waste to the use of natural resources like palm and soy, the beauty industry has significant environmental effects. Every year, 120 billion waste units are produced by beauty packaging, harmful chemicals also exist in certain cosmetics. Numerous entrance points allow nano and microplastics to infiltrate marine food webs, where they can then cycle through various biotic compartments. This review additionally highlights the necessity of all-encompassing approaches, such as public awareness campaigns, legislative interventions and sustainable waste management techniques to track, control and lessen microplastic contamination. Resolving this issue is crucial to protecting human livelihoods and maintaining the health of India's marine ecosystems.

The deep-sea floor encompasses more than half of the surface of our planet, yet the extent and distribution of deep-sea biodiversity and its contribution to large biogeochemical cycles remain poorly understood. This knowledge gap stems from several factors, including sampling issues, the magnitude of the work required for morphological inventories, and the difficulty of integrating results from disparate local studies. The application of meta-omics to environmental DNA now makes it possible to assemble interoperable datasets at different spatial scales to move towards a global assessment of deep-sea biodiversity. We present a large-scale dataset on deep-sea biodiversity, with data and metadata openly accessible at ENA and Zenodo. The resource was generated using standardized protocols developed according to FAIR principles, covering fieldwork through bioinformatic analysis, within “Pourquoi Pas les Abysses?” and eDNAbyss projects. Together with information ensuring reproducibility, this dataset —combining metagenomics, metabarcoding across the Tree of Life and capture-by-hybridization— contributes to the international concerted effort to achieve a holistic view of the biodiversity in the largest biome on Earth.

Abstract. This study presents high-resolution hydroacoustic datasets covering over 7000 km2 of Polish Marine Areas in the Southern Baltic, acquired between April 2022 and December 2023 as part of a national initiative to map benthic habitats using advanced sonar technologies. Utilizing a fleet of seven vessels and the expertise of approximately 250 personnel, the project collected bathymetric and side-scan sonar data along more than 95 000 km of survey lines, adhering to International Hydrographic Organization S-44 Order 1a standards. The resulting datasets include detailed bathymetric grids at 50 cm×50 cm resolution and side-scan sonar backscatter mosaics at 20 cm×20 cm resolution, with robust quality control ensuring at least 95 % data completeness per grid cell. These data provide unprecedented insight into the underwater topography and sediment characteristics of the region, supporting applications in scientific research, environmental management, offshore wind farm planning, and underwater archaeology. The datasets, available at DOI: https://doi.org/10.26408/southern-baltic-hydroacoustic-datasets (Janowski et al., 2025), lay a solid foundation for future studies and the development of science-informed policies to promote sustainable and resilient marine ecosystems in the Baltic Sea.

Abstract. Organic carbon stored in continental margin sediments might be at risk by widespread mobile bottom fishing, potentially leading to reductions of organic carbon stocks, increased ocean acidification, additional atmospheric carbon dioxide emissions and a reduction of the buffering capacity of the ocean. Spatially explicit studies that have been conducted to inform marine management have so far looked at organic carbon stocks that have already been affected by mobile bottom fishing. Here, we focus instead on areas on the Norwegian continental margin that are currently not fished, based on fishing data covering the years 2009–2020. Using these data and spatial prediction methods, we estimate that the surface sediment layer (0–2 cm) in unfished areas covering 765 600 km2 contains 139.2 Tg of organic carbon. Based on data from a meta-analysis of demersal fishing impacts on organic carbon density and estimated reductions in sediment thickness due to fishing-induced erosion, we estimate that 18.7 Tg (1.9–33.5 Tg) of organic carbon might be lost due to mobile bottom fishing in a scenario where each grid cell is fished evenly over the entire area and down to the full depth of the surface layer. Approximately one third of this vulnerable organic carbon is currently located in existing area-based protection measures. Additional protection could be guided by hotspots of vulnerable organic carbon, which are mainly found in the Barents Sea. We argue that the protection of vulnerable organic carbon that is at high risk of being lost e.g. in areas becoming accessible to fishing due to sea ice retreat such as in the northern Barents Sea should be given a high priority.

ABSTRACT Objective Reproductive activity is rarely observed directly in the White Sturgeon Acipenser transmontanus because spawning generally occurs over benthic habitats in fast-flowing rivers. Aspects of reproductive ecology have been inferred from indirect lines of evidence, with results often being imprecise. Here we performed parentage analysis within the population of the upper Columbia River, associating adults with offspring that had been collected from multiple years and locations, to precisely characterize spawning periodicity across years, spawning duration within years, and spawning site fidelity across locations. Methods We identified parent–offspring relationships by integrating Mendelian-mismatch-based exclusion, likelihood-based assignment, and relationship coefficient analysis, using tetrasomic single-nucleotide polymorphism genotypes that were produced through genotyping-in-thousands by sequencing. The thresholds for each approach were determined from known parent–offspring relationships in a cultured population. Results Parent–offspring relationships associated adults of both sexes with multiple spawning events across years, within years, and across locations. Among adults that were linked to multiple years, spawning periodicity ranged from 1 to 5 years in males and 4 to 5 years in females. Among adults that were associated with multiple spawning dates within years, we observed spawning durations of up to 26 d in males, whereas females largely displayed durations up to 4 d. Individuals of both sexes were associated with different sites in different years, whereas males were further linked to different sites within years, suggesting incomplete spawning site fidelity. Conclusions These findings inform an ongoing conservation aquaculture program for supplementing this population and demonstrate the utility of parentage analysis for inferring reproductive behaviors in high detail, particularly in systems where thorough sampling of parents and offspring is feasible.

High-resolution predictive mapping reveals novel benthic habitats in the southern Baltic Sea.

Weathered microplastics alter deep sea benthic biogeochemistry and organic matter cycling: insights from a microcosm experiment.

Prediction of seafloor ecological state using 16S nanopore sequencing.

Benthic-pelagic coupling, the reciprocal exchange of materials between benthic and pelagic habitats, has traditionally emphasised pelagic influences on benthic systems. Yet, the role of benthic biological processes in shaping pelagic microbial dynamics remains underexplored. We investigated how surfgrass and mussels regulate nitrogen and dissolved organic matter (DOM) cycling and their cascading effects on heterotrophic bacteria in Oregon tide pools. We quantified biogeochemical fluxes and bacterial responses before and after foundation species removal during contrasting upwelling regimes. Mussel-dominated pools released high concentrations of ammonium and nitrate, while surfgrass pools transformed DOM that fueled bacterial growth; upwelling intensified these benthic-pelagic linkages. Removing foundation species dampened nutrient release in mussel pools and reduced DOM-fueled bacterial growth in surfgrass pools, ultimately decoupling benthic productivity from pelagic microbial growth. Our results demonstrate the critical role of foundation species to pelagic microbial processes and underscore the vulnerability of coastal microbial dynamics to their global decline.

Benthic habitat influences sea scallop distributions and swimming behavior based on underwater imagery and machine learning

Massive wastewater discharge severely impacts a whole eutrophic coastal lagoon ecosystem.

Pockmarks are ubiquitous seafloor depressions formed by the fluid/gas seepage through marine sediments, with implications for geohazards, benthic ecosystems, and climate-related processes. Despite extensive research, the mechanisms controlling the formation and spatial distribution of pockmarks are not completely understood, owing to the diverse and site-specific geo-environmental conditions. In this study, we provide a first review of over 7500 pockmarks mapped across the Mediterranean and Black seas, showing their relationship with depth range, slope gradient, seafloor lithology, proximity to tectonic faults, and sediment thickness. Our analysis reveals that pockmarks are predominantly located at intermediate water depths (100–700 m), with two main clusters around 100–200 and 500–700 m. They are commonly found on gently sloping seafloor (<4°), often clustering around slope breaks. In detail, two slope-related peaks around 1.5° and 3.5° suggest distinct geological settings for pockmark formation: sediment-rich and low-energy environments versus more dynamic slope domains. Fault proximity plays a critical role, with over 40% of pockmarks occurring within 1 km of mapped faults, indicating that structural discontinuities act as preferential fluid pathways. Pockmarks concentrate in areas with moderate Plio-Quaternary sediment thickness (300–600 m), suggesting an optimal window for overpressure generation and fluid expulsion. A strong lithological control is evident: 74% of pockmarks occur on muddy sand or sand-rich substrates. In terms of ongoing to recent seepage/activity, ~27% of pockmarks show evidence of ongoing fluid seepage (e.g., acoustic gas flares, seismic wipeouts), particularly in regions such as the Black Sea, Aegean, and Central Tyrrhenian, where faulting, salt tectonics, or hydrothermal systems enhance permeability. Conversely, pockmarks in the Western Mediterranean appear to be generally inactive and buried. These findings underscore the influence of tectono-sedimentary architecture on seafloor fluid escape and provide essential insight into methane seepage, slope stability, and benthic habitats. This pedagogic review enhances our understanding of pockmark systems and establishes a foundation for future geohazard assessment, climate studies, and marine resource exploration.

Diving marine mammals must allocate time between respiring at the surface and foraging underwater. Previous studies of optimal diving theory have attempted to predict such patterns, but the amount of time divers must spend at the surface before and after dives of varying durations remains difficult to assess. Here, we examined the surfacing and breathing patterns of short-finned pilot whales (Globicephala macrorhynchus) from biologger data to examine their use of anticipatory versus reactive strategies. We used linear mixed-effects models to examine the effect of dive characteristics on surface interval (SI) durations and breathing rate. Pilot whales increased SI duration before dives of increasing duration and after dives of increasing activity. Instantaneous breathing rates (fRs) of pilot whales demonstrated little anticipation but rather a strong reactive pattern seen by the modulation of fR in response to the previous rather than upcoming dive. During typical SIs, fR was predicted by time since previous dive, duration of the previous dive, time until upcoming dive, and activity of the previous dive. Short-finned pilot whales in our study area exhibit both benthic and pelagic foraging, which may compel anticipation when prey capture is predictable and reaction when prey capture is difficult to predict. The observed surfacing and breathing patterns therefore likely reflect a balance of the needs for blood gas homeostasis, aerobic metabolism, and the variability of foraging opportunities. An improved understanding of how animals make decisions about diving is critical for informing predictions of how they will contend with changing ocean landscapes.NEW & NOTEWORTHY A new study reveals how short-finned pilot whales balance the conflicting demands of foraging underwater with breathing at the surface. Using data from digital tags, scientists found that pilot whales rely more on surfacing strategies that react to the effort of a dive rather than anticipate. Their use of such strategies may reflect variation in the ability to predict prey capture in benthic and pelagic habitats.