The Argentine shelf-break front is of high ecological and economic importance and supports diverse benthic communities and key life-history processes of several commercial species. This study provides the first comprehensive synthesis of reproductive traits among benthic invertebrates inhabiting this area of the southwestern Atlantic Ocean (80-120 m depth). Information was compiled for 126 epibenthic species belonging to Porifera, Cnidaria, Annelida, Mollusca, Brachiopoda, Echinodermata, Arthropoda, Bryozoa, and Chordata (> 1 cm) from published sources, aiming to identify the dominant reproductive strategies that sustain populations persistence over time. Species-specific reproductive data were available for only 47% of the taxa, and for only five species (~ 4%) such information derived from specimens collected at the shelf-break front itself. Despite data gaps and the need for extrapolation from related taxa or regions, this synthesis reveals predominant reproductive patterns among benthic invertebrates and provides essential baseline knowledge for ecosystem-based management. Approximately 68% of the species are gonochoric, although most sponges and all ascidians are hermaphroditic, while 43% can reproduce asexually or have the ability of regeneration. Internal fertilization predominates (71%), while all bivalves and polychaetes reproduce by external fertilization. Parental care, defined as any kind of protection of embryos through incubation or encapsulation, occurs in 61% of the species, being universal among crustaceans and frequent in gastropods (89%). Indirect development characterizes 82% of the species, of which 59% produce lecithotrophic larvae and 33% planktotrophic larvae. Understanding reproductive modes and dispersal capacities is crucial to assess connectivity, resilience, and vulnerability of benthic communities in the Argentine shelf-break front.

The angel shark Squatina guggenheim has been historically caught as bycatch and landed in the Argentine hake Merluccius hubbsi fishery, and since 2013, in the Argentine red shrimp Pleoticus muelleri fishery in the San Matías Gulf (SMG). The aim was to evaluate the feeding habits of the angel shark in the SMG during period 1 (P1, 2005-2010) and period 2 (P2, 2015-2022). Stomach contents of 334 individuals were analyzed, 152 from P1 and 182 from P2. The incidence of prey species in the diet was calculated using frequency of occurrence (%FO), numerical percentage (%N), percentage by weight (%P), the relative importance index IRI, %IRI, and specific %PSIRI. Results from P1 indicate a diet dominated by hake (84.3%IRI). In P2, the diet was mainly hake (42.5%IRI), with an increase in malacostracan invertebrates, including shrimp (22.6%IRI), squat lobster (14.6%IRI), and stomatopods (8.9%IRI). This dietary shift is reflected in the calculated trophic level (TL) through the standardized index of diet composition according to Cortés (1999); in P1, sharks were tertiary predators, with TL = 4.22 in adults and TL = 4.16 in juveniles. Based on prey and their trophic levels, P2 showed TL = 3.77 in adults and TL = 3.81 in juveniles, placing angel sharks as secondary predators. The results highlight the species’ feeding plasticity, shifting its diet according to prey availability and showing a feeding strategy with strong individual specialization during both periods.

The fishing footprint, which reflects humanity’s demand on marine ecosystems and is closely linked to fisheries sustainability, serves as the main environmental indicator for marine resources. This study investigated the role of schooling as an indicator of human capital in shaping the fishing footprint in Greece over the period 1990-2022. The empirical analysis employed the Augmented ARDL (AARDL) approach, concentrating on the potential nonlinear relationship between human capital and environmental degradation in fishing grounds. The findings reveal the threshold effects of schooling: while lower levels of human capital increase environmental pressure, once a certain threshold is surpassed, human capital contributes to reducing environmental degradation in fisheries. Furthermore, the results validate the Environmental Kuznets Curve (EKC) and Environmental Phillips Curve (EPC) hypotheses in the context of fishing grounds.

Fish genomics has become an essential tool to explore the genetic basis of biological processes, such as biodiversity, evolution, and adaptation, as well as for direct applications in conservation, aquaculture, and fisheries management. Argentina, home to more than 1,100 fish species and diverse aquatic ecosystems, holds enormous potential for genomic research. Although historically underrepresented in global databases, recent progress (including genome sequencing of commercially and ecologically important species) signals growing momentum in the field. This note provides an overview of the current state of fish genomics in Argentina, highlights notable contributions, and underscores the need for high-quality genome assemblies, national coordination, and broader taxonomic coverage to ensure that the country’s biodiversity is adequately represented and preserved.

Marine recreational fishing, a recreational and leisure activity for those who practice it, is a tourist attraction in Argentina and is regulated in several maritime provinces. However, there is little research that characterizes this activity or addresses its socio-ecological aspects. In this study, four interconnected actions were carried out, the objective of which was to carry out a socio-ecological analysis of the problem of litter derived from marine recreational fishing in the city of Mar del Plata, which represents the main angling site of southeastern Buenos Aires province, namely: (1) a survey in the angling location to characterize and quantify the litter derived from marine recreational fishing activities, (2) an intervention that addressed the behavior of recreational fishermen, (3) a survey in baskets specifically designed for the disposal of litter derived from recreational fishing to monitor and quantify the effect of said intervention, and (4) non-participant observations and semi-structured interviews to analyze the perceptions of key actors. This work constitutes an initial socio-ecological characterization of the problem of litter derived from recreational marine fishing, including an essay aimed at promoting responsible management of said litter at an emblematic angling point on the Buenos Aires maritime coast such as the North Breakwater of the Port of Mar del Plata.

This study presents the first estimates of primary production (PP) from the Marine Ecological Time Series, Estación Permanente de Estudios Ambientales (EPEA) in the Argentine Sea and examines its relationship with phytoplankton community composition and environmental factors using data obtained between 2006 and 2019. Our findings indicate that PP at EPEA exhibits seasonal pulses, with an estimated annual average of 202 ± 115 g C m-2 yr-1, classifying the system as mesotrophic. The peak of PP occurred in spring associated with increased irradiance and water column stratification, and the dominance of diatoms, dinoflagellates, and haptophytes. Winter was the least productive season, characterized by low light levels and a deep mixed layer, with a prevalence of cryptophytes and ultraphytoplankton. In summer, PP was lower than in spring, and the community was dominated by picoplanktonic Synechococcus spp., adapted to low nutrients and high light. In autumn, PP increased relative to summer, associated with higher microphytoplankton biomass. A key finding was the decoupling between PP and total carbon biomass, highlighted by the high variability of the BC to ChlaS (BC/ChlaS) ratio. This ratio is crucial for linking carbon-based biogeochemical models with satellite-based PP models. Deviations from the expected seasonal patterns could point to the sensitivity of coastal PP to large-scale climate influences, such as the Southern Annular Mode (SAM) and the El Niño-Southern Oscillation (ENSO). Our results evidence the physiological adaptability of phytoplankton in this dynamic coastal environment and highlight the necessity of high-frequency sampling to improve primary productivity models in this under-sampled region.

The above article from Marine and Fishery Sciences (MAFIS) 35(3): 431-436 (https://doi.org/10.47193/mafis.3532022010902) has been retracted. The author has requested retraction after identifying that some data included in the article were not authorized for publication. Their inclusion was inadvertent, and the retraction is issued to maintain the integrity of the scholarly record.

The marine catfish Genidens barbus is a benthic and anadromous species distributed from Brazil to southern Argentina. Its presence during the non-reproductive period remains poorly documented. This study reported the first confirmed record of a female G. barbus outside the reproductive season, which was incidentally caught in the artisanal Argentine red shrimp (Pleoticus muelleri) fishery off the coast of Río Negro, Argentina (41° 05′ S-64° 03′ W) at a depth of 70 m. This finding provides novel evidence for the Patagonian population, suggesting that the species may occupy deeper marine habitats during non-reproductive periods. The presence of P. muelleri in the stomach content reinforces its benthophagous feeding habit and trophic association with the coastal benthic community. This record expands the current knowledge of the seasonal and ecological distribution of G. barbus, as well as conservation strategies. Given its status as a vulnerable species and the limited information available on its behavior outside estuaries, this finding makes a significant contribution to our understanding of Patagonian ichthyofauna and the sustainable management of its populations.

Xystreuris rasilis (Jordan 1891) is a flounder species from the southwestern Atlantic, perticularly abundant in high-salinity waters of the Buenos Aires Coastal Ecosystem and San Matías Gulf. It primarily feeds on benthic invertebrates and utilizes local frontal systems as breeding and nursery grounds. Analysis of a 406 bp fragment of the mitochondrial control region revealed high haplotype (h = 0.994) and nucleotide (n = 0.022) diversities. Genetic divergence between Necochea and San Antonio Oeste was low and not significant, with 18 unique haplotypes and no evident phylogeographic structure. Demographic analyses indicated long-term population stability, with the most recent common ancestor estimated at approximately 148,000 years ago. Results do not provide evidence for the existence of two discrete genetic units. Nevertheless, it is possible that the species experienced historical isolation followed by secondary contact between different lineages of the flounder X. rasilis.

Microfibers (MFs) are an anthropogenic pollutant with a major impact on the marine environment. Due to their size, they can be ingested directly (from the environment) or indirectly (with their prey) by organisms. The aim of this study was to analyze and compare the occurrence, abundance and physicochemical characteristics of MFs present in Patagonotothen kreffti from the Marine Protected Area Namuncurá/Burdwood Bank (MPA N/BB) during two seasons: winter and spring. The notothenioids were obtained from the oceanographic surveys of August 2018 and December 2018. Oxidative digestions of fish gastrointestinal tracts were used to recover MFs and further determine the number per individual (MFs ind-1) and per gram of tissue (MFs g-1). Each MF was characterized by total length, color, wear and discoloration, and chemical composition. In winter, P. kreffti presented an occurrence of 100% with values of 5.71 ± 3.19 MFs ind-1 and 1.22 ± 1.45 MFs g-1, while in spring the occurrence was 85.71%, with abundances of 3.71 ± 3.30 MFs ind-1 and 0.28 ± 0.23 MFs g-1, with no significant differences between seasons (Wilcoxon, p > 0.05). The mean size of the MFs was 0.89 mm, and blue MFs were in the majority (57.35%). Wear and discoloration were observed in 42.42% of the MFs. Cellulose MFs were the most abundant followed by polyester MFs. P. kreffti could be used to assess MF contamination in the N/BB MPA because it is endemic and has higher abundances of MFs than other notothenioids in the area.