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Cheilodactylus variegatus is an abundant carnivorous demersal reef fish that lives in the shallow subtidal of the north-central Chilean coast. Characteristically, these environments are dominated by kelp forests of Lessonia trabeculata. This species preys on a great variety of benthic invertebrates, and shows particularly high consumption rates on amphipod crustaceans. In our study, two widely separated populations of C. variegatus were considered (central and northern Chile). Individuals that form part of these populations show considerable differences in their distribution, abundance and trophic behavior. In the northern zone, the species is abundant and both juveniles and adults are distributed along the whole bathymetric gradient. This contrasts with populations found in central Chile, which are more sparse and lack juveniles. The distribution and abundance patterns appear to be influenced mainly by the great abundance of diverse understory macroalgae in the northern subtidal, which harbors a large number of invertebrates, especially amphipods. In contrast, the understory algal abundance of the central zone is much lower, and does not show a direct relationship with the lesser abundance of amphipods. In general, C. variegatus maintains a high consumption rate on amphipods throughout its ontogeny but it includes several other prey items in later ontogenetic stages. The different understory algal assemblages, and their associated fauna, are likely to be the main factors influencing the patterns of abundance and distribution observed between these two geographically distinct fish populationsCheilodactylus variegatus es un pez demersal abundante que habita el submareal somero de la costa norte y central de Chile. Es característico de estos ambientes el estar dominados por praderas del alga Lessonia trabeculata. Esta especie incorpora en su dieta una variada gama de invertebrados bentónicos, mostrando una tasa particularmente alta de consumo de crustáceos anfípodos. En nuestro estudio, se consideró dos poblaciones ampliamente separadas de C. variegatus (centro y norte de Chile). Los individuos que integran estas poblaciones exhiben claras diferencias en su distribución, abundancia y comportamiento trófico. En la zona norte, la especie es abundante y tanto juveniles como adultos se distribuyen a lo largo de todo el gradiente batimétrico. Esto contrasta con las poblaciones de la zona central de Chile, las que están más dispersas y desprovistas de juveniles. El patrón de distribución y abundancia parece estar principalmente influenciado por la gran abundancia de diversas especies de macroalgas que conforman el subdosel en el submareal del norte, el que es habitado por un gran número de invertebrados, especialmente anfípodos. En contraste, la abundancia de algas del subdosel de la zona central es mucho menor y no muestra una relación directa con la menor abundancia de anfípodos observada. La tasa de consumo que C. variegatus ejerce sobre anfípodos es en general alta durante toda su ontogenia, incorporando a otros ítems presa en estadíos ontogenéticos posteriores. Es posible que los diferentes ensambles de diversas algas de subdosel, junto con su fauna asociada, sean el principal factor que afecta los patrones de abundancia y distribución observado entre estas dos poblaciones de peces geograficamente distintas

The coastal environment is not managed in a way that considers the impact of cumulative threats, despite being subject to threats from all realms (marine, land, and atmosphere). Relationships between threats and species are often nonlinear; thus, current (linear) approaches to estimating the impact of threats may be misleading. We developed a data‐driven approach to assessing cumulative impacts on ecosystems and applied it to explore nonlinear relationships between threats and a temperate reef fish community. We used data on water quality, commercial fishing, climate change, and indicators of recreational fishing and urbanization to build a cumulative threat map of the northern region in New South Wales, Australia. We used statistical models of fish abundance to quantify associations among threats and biophysical covariates and predicted where cumulative impacts are likely to have the greatest impact on fish. We also assessed the performance of no‐take zones (NTZs), to protect fish from cumulative threats across 2 marine protected area networks (marine parks). Fishing had a greater impact on fish than water quality threats (i.e., percent increase above the mean for invertivores was 337% when fishing was removed and was 11% above the mean when water quality was removed inside NTZs), and fishing outside NTZs affected fish abundances inside NTZs. Quantifying the spatial influence of multiple threats enables managers to understand the multitude of management actions required to address threats. [ABSTRACT FROM AUTHOR]

The diets of the most conspicuous reef-fish species from northern Patagonia, the carnivorous species Pseudopercis semifasciata, Acanthistius patachonicus, Pinguipes brasilianus and Sebastes oculatus were studied. Pinguipes brasilianus had the narrowest diet and most specialized feeding strategy, preying mostly on reef-dwelling organisms such as sea urchins, limpets, bivalves, crabs and polychaetes. The diet of A. patachonicus was characterized by the presence of reef and soft-bottom benthic organisms, mainly polychaetes, crabs and fishes. Pseudopercis semifasciata showed the broadest spectrum of prey items, preying upon reef, soft-bottom and transient organism (mainly fishes, cephalopods and crabs). All S. oculatus guts were empty, but stable-isotope analyses suggested that this species consumed small fishes and crabs. In general, P. brasilianus depended on local prey populations and ate different reef-dwelling prey than the other species. Pseudopercis semifasciata, A. patachonicus and probably S. oculatus, however, had overlapping trophic niches and consumed resources from adjacent environments. The latter probably reduces the importance of food as a limiting resource for these reef-fish populations, facilitating their coexistence in spite of their high trophic overlap. [ABSTRACT FROM AUTHOR]

The occurrence of the dusky grouper Epinephelus marginatus in northern Patagonian Gulfs San Matías and Nuevo, Argentina, is recorded. This finding represents the southernmost record of the species for the southern hemisphere. [ABSTRACT FROM AUTHOR]

Examines the extension of the distributional range of the silver porgy, Diplodus argenteus, and the red porgy, Pagrus pagrus in northern Patagonia in the southwestern Atlantic. Species richness of the fish assemblage that inhabits nearshore rocky reefs in northern Patagonian gulfs; Components of the fish from different biogeographic provinces; Area map showing locations where sparids were caught during spearfishing tournaments.

The article presents the presence of male namorado sandperch, Pseudopercis numida in a reef near Pardelas Beach, Nuevo Gulf, Argentina. The presence of which as suggested by literature review was due to introduction into the Nuevo Gulf by transport in water ballast of freighters arriving in Puerto Madryn from Brazil. Profiles of the fish as well as other explanation of its presence are discussed.