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Este artículo contiene 9 páginas, 9 figuras, 2 tablas. ; Submarine canyons aggregate numerous marine species and can affect the structure of benthic communities. However, analyses dedicated to assess the spatial distribution variability among several canyons are rare. In the northwestern Mediterranean Sea, three major submarine canyons consecutively indent the narrow margin. There,theabundanceofdeep-seablueandredshrimpAristeusantennatus(Crustacea:Decapoda),oneofthemost important fishery-targeted species in the western and central Mediterranean Sea, sustains relatively high incomes for the nearest fishing harbors. To date, the spatial distribution of this shrimp species has only been assessed on known fishing grounds, but it has neither been modeled simultaneously covering several submarine canyons nor according to the environmental conditions. In this study, we aimed to look over the spatiotemporal shrimp distribution in a region of the northwestern Mediterranean Sea with a particular interest in variations in the three submarine canyons. From summer landing data between 2005 and 2014, we implemented a species distribution model with georeferenced catches linked to environmental data of the shrimp habitats. The model showed that the bottom topography was one of the most essential variables to explain the spatial distribution of the catches and that the highest catch rates were between 475 m and 575 m depth. Overall, two canyons (Blanes and Palamós) sheltered high estimates of catches on the shallow and narrow part of their margins (at 510 and 565 mdepth). Amongthem, 60%ofestimatedsummercatchescamefromthePalamósCanyon, butthisestimate shifted to the Blanes Canyon in summer 2008, probably due to variations in fishing fleet behavior. Modeled hypothetical temperature changes scenarios (to 1 °C warmer than the average) suggested the shrimp catches would decrease lessinthe BlanesCanyon (3% fewercatchesthan the average) than inthePalamós Canyon (20% fewer catches than the average). The information produced by the species distribution model allowed setting spawning locations and depths, which is useful to better understand the canyon influence on benthic communities and to parameterize larval transport models. ; M.C.-H. was fundedby aPhD grant(BES-2015-074126) provided by the Spanish Government. This study was carried out within the Spanish project CONECTA (CTM2014-54648-C2-1-R) lead from theICM-CSIC in Barcelona (ES). ; With the funding support of the 'Severo Ochoa Centre of Excellence' accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI). ; Peer reviewed

15 pages, 9 figures, supplement https://doi.org/10.5194/os-15-1745-2019 ; Marine biophysical models can be used to explore the displacement of individuals in and between submarine canyons. Mostly, the studies focus on the shallow hydrodynamics in or around a single canyon. In the northwestern Mediterranean Sea, knowledge of the deep-sea circulation and its spatial variability in three contiguous submarine canyons is limited. We used a Lagrangian framework with three-dimensional velocity fields from two versions of the Regional Ocean Modeling System (ROMS) to study the deep-bottom connectivity between submarine canyons and to compare their influence on the particle transport. From a biological point of view, the particles represented eggs and larvae spawned by the deep-sea commercial shrimp Aristeus antennatus along the continental slope in summer. The passive particles mainly followed a southwest drift along the continental slope and drifted less than 200 km considering a pelagic larval duration (PLD) of 31 d. Two of the submarine canyons were connected by more than 27 % of particles if they were released at sea bottom depths above 600 m. The vertical advection of particles depended on the depth where particles were released and the circulation influenced by the morphology of each submarine canyon. Therefore, the impact of contiguous submarine canyons on particle transport should be studied on a case-by-case basis and not be generalized. Because the flows were strongly influenced by the bottom topography, the hydrodynamic model with finer bathymetric resolution data, a less smoothed bottom topography, and finer sigma-layer resolution near the bottom should give more accurate simulations of near-bottom passive drift. Those results propose that the physical model parameterization and discretization have to be considered for improving connectivity studies of deep-sea species ; Funding was provided through the CONECTA project supported by the Ministerio de Economia, Industria y Competividad from the Spanish Government. Morane Clavel-Henry is funded under an FPI PhD program of the Spanish Government (grant no. BES-2015-074126) ; Peer Reviewed