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In the deep-sea, abundant and diverse biological communities tend to occur in areas where combinations of geological, physical and biological processes locally enhance trophic-wide productivity, sustaining aggregations of consumers and top predators. These areas are 'productivity hotspots' and their delimitation should improve the effectiveness of area-based strategies designed to manage human activities and protect the deep-sea. We explored the premise that fishing operations in association with geomorphological features are effective surrogates for delimiting productivity hotspots distribution in the Brazilian Meridional Margin (BMM; 18°S - 35°S; 200 – 3300 m). We described along-slope and across-slope geoforms and related them with catch patterns of fishes, deep-sea shrimps, deep-sea crabs and squids in 23565 fishing hauls conducted between 2000 and 2007. Over 97% of the total catch was obtained in Santos (42.7%) and Pelotas (54.8%) sedimentary basins. In the former, 55.7% of all fishing hauls and 38.6% of the catch were obtained from one of 12 slope geoforms, which covered 22% of the available fishing area. In the Pelotas basin, a shelf break geoform covering 6% of the fishing area concentrated 29.5% of the fishing hauls and 30.2% of the catch. Best fit delta-lognormal Generalized Linear Models (explaining >50% of the total variance) highlighted the positive effect of shelf break embayments of Santos Basin in occurrence and abundance of the pool of species targeted by fisheries. Within these embayments, sectors incurvated and excavated by erosive action of the Brazil Current positively affected abundance and occurrences of fishes and deep-sea shrimps, respectively. The upper slope (300 – 500 m depths) were particularly favorable for fishes and squid concentrations, whereas the lower slope (600 – 800 m depths) increased the probability of deep-sea shrimp catches. We propose that the Santos Basin shelf break embayments host mesoscale and sub-mesoscale productivity hotspots, sustained by biophysical processes promoted by the Brazil Current flow, coupled with biological active transport of pelagic and demersal vertical migrators, some of them targeted by bottom fisheries. We advocate that these are unique features, in the otherwise oligotrophic SW Atlantic subtropical gyre, that should be taking into consideration in regional systematic conservation plans. [ABSTRACT FROM AUTHOR]

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Commercial trawling on the Atlantic slope areas off Brazil intensified in the late 1990's owing to the expansion of coastal trawling areas and the operations of a chartered foreign fleet. Between 2000 and 2003, 59 fishing trips conducted by 10 chartered trawlers were intensely monitored by observers and satellite vessel monitoring systems, totaling 9,069 tows and 30,085.2 trawling hours. Fishing operations occurred in northern, northeastern, southeastern, and southern sectors of the Brazilian coast in 60-1,173 m depths. Total retained and processed catch were 8,074.6 t and 6,479.8 t, respectively. Argentine hake, Merluccius hubbsi; and Argentine shortfin squid, Illex argentinus, were the primary species taken contributing to 41.1 % and 28.6% of the overall catch, respectively. The silver John dory, Zenopsis conchifera; monkfish, Lophius gastrophysus; Brazilian codling, Urophycis mystacea; and the black grouper, Epinephelus nigritus, composed 23% of total processed catch, and the remaining 7.2% was composed of deep-sea shrimps (family Aristeidae) and other teleosts and elasmobranches. The occupation of slope areas included an early exploratory phase, followed by directed phases of the upper slope (300-500 m), aiming principally at the Argentine hake, and the lower slope (>700 m), targeting valuable concentrations of deep-sea aristeid shrimps. The role of chartering for slope trawling development was critically addressed. We conclude that chartered vessels were efficient explorers and were particularly important in areas not available to the technologically limited national fleet. Because the charters were market-oriented and had elevated profit demands, however, those vessels quickly turned from exploration to exploitation and competed with national trawlers in shallower areas and produced significant impacts on Brazil's modest deep-sea resources., Introduction Large-scale trawl fishing development around the world has been principally associated with the occupation of productive continental shelf areas ( The continental shelf off Brazil encompasses 911,000 [km.sup.2] bathed [...]