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The exact number of cetacean species present in Mauritanian waters is unknown. A first overview was published only in 1980, the latest in 1998. Yet, published information remains modest compared to e.g. neighbouring Senegal (first review in 1947). The complex oceanography of Mauritanian waters permits a mixed assemblage of cetacean fauna, with the distribution of both cool temperate and (sub)tropical species. In this updated review, we use our own observations from strandings, bycatches and vessel-based surveys, as well as published and grey literature, to support an inventory of cetaceans of Mauritania. The updated checklist includes two new authenticated species records: Kogia sima and Lagenodelphis hosei. Stenella coeruleoalba is verifiably documented for the first time. Further, a first specimen record of Stenella longirostris is presented, as well as new (second) specimens of Mesoplodon europaeus, Steno bredanensis and Megaptera novaeangliae. Revised evidence shows that of 30 reported species, 27 of 6 families are provably supported while 3 species lack (accessible) voucher material but probably (P) occur in Mauritania: Megaptera novaeangliae, Balaenoptera musculus, B. borealis, B. omurai, B. acutorostrata, B. physalus, B. brydei (P), Physeter macrocephalus, Kogia sima, K. breviceps, Sousa teuszii, Tursiops truncatus, Delphinus delphis, Stenella frontalis, S. attenuata, S. coeruleoalba, S. longirostris, S. clymene, Steno bredanensis, Peponocephala electra (P), Lagenodelphis hosei, Grampus griseus, Globicephala macrorhynchus, G. melas (P), Orcinus orca, Pseudorca crassidens, Ziphius cavirostris, Mesoplodon europaeus, M. densirostris and Phocoena phocoena. Finally, a first case of tattoo skin disease (TSD) is reported for continental NW Africa, in a stranded D. delphis.

Pagellus acarne, Pagellus bellottii, Pagellus bogaraveo and Pagellus erythrinus are sparids distributed throughout Large Marine Ecosystems (LMEs), the Iberian Coastal region (25) and Canary Current region (27). They are target species due to their important commercial value to local and international fleets from three different continents: Africa, Asia and Europe. Given the high exploitation interest of these species, sustainable management of the resource is essential. For this reason, a key element for its implementation is the knowledge of the historical behaviour of catches by geolocalised areas. To this end, marine catches reconstructed in total wet-weight tonnes from 1950 to 2014 from the Sea Around Us database were analysed. A total of 2,058,172.60 tn of species of the Pagellus genus were caught for the entire region, of which 83.20% (1,712,552.21 tn) corresponded to the Canary Current area and the remaining 16.79% (345,620.38 tn) to the Coastal Iberian area. The dominant area was Canary Current; its catches were higher than those of the Coastal Iberian area, with an annual average percentage of 78.21%. Overall, the fishery showed a negative trend of −511.37 tn/year. In terms of species, 61.52% of the catches were of Pagellus bellottii (1,266,219.36 tn), 20.04% of Pagellus sp (not identified at species level, only to genus) (412,482.53 tn), 8.91% of Pagellus erythrinus (183,434.67 tn), 6.74% of Pagellus bogaraveo (138,717.29 tn) and the remaining 2.78% of Pagellus acarne (57,318.74 tn). Our results suggest the existence of important variations in the reconstructed catches of the four species analysed in two large marine ecosystems, showing an overall decreasing behaviour. Canary Current was undoubtedly the region with the highest fishing pressure during the 65 years analysed and Pagellus bellotii was the dominant species in the Current Canary region and in the whole region. This multispecies analysis presented could help the development of sustainable management protocols by providing insight into the historical evolution and status of the reconstructed catches for large marine ecosystems, This research was funded by the Government of Spain Ministry of Science, Innovation and Universities with a FPU fellowship, grant number (FPU17/04298)

The work was funded by the Natural Environment Research Council (Standard Research Grant NE/H007466/1) and donations from Evan Fountain (In Memoriam donations for Issy Fountain) and Mike Matthewson. Marine vertebrates show a diversity of migration strategies, including sex differences. This may lead to differential demography, but the consequences of such between-sex variation are little understood. Here, we studied the migration of known-sex northern gannets Morus bassanus — a partial migrant with females ~8 % heavier than males. We used geolocators to determine wintering areas of 49 breeding adults (19 females and 30 males during 2010 to 2014) from 2 colonies in the northeast Atlantic (Bass Rock and Grassholm, UK). We also tested for sex-specific survival probabilities using capture−mark−recapture methods (n = 72 individuals Bass Rock, n = 229 individuals Grassholm; 2010−2018) and applied sex-specific population projection matrices (PPMs) to quantify population-level effects. Tracked gannets wintered in a range of large marine ecosystems (LMEs): Canary Current LME (CCLME; 69 %), Celtic-Biscay Shelf LME (16 %), Iberian Coastal LME (8 %), North Sea LME (4 %) or Mediterranean LME (2 %). Migratory destination differed between the sexes: 90 % of females vs. 57 % of males wintered in the CCLME. Survival was similar between the sexes at Bass Rock (mean ± 95 % CI = 0.951 ± 0.053 and 0.956 ± 0.047 for females and males, respectively). At Grassholm, there was evidence of slight sex differences in breeder survival: females had lower annual survival (0.882 ± 0.040) than males (0.946 ± 0.026). At Bass Rock, PPMs with no sex effect best fitted the observed population increase (1994−2014). Sex-specific PPMs fitted the population estimates for Grassholm (1995−2015). Our results reveal that female gannets are more likely to travel further than males to winter in the CCLME. This difference is unlikely due to morphological differences, unlike in other bird species. However, the reason for slightly higher over-winter female mortality at Grassholm is unclear. Publisher PDF

Zooplankton vertical distribution, migrant biomass, and respiratory flux were studied in two transects performed in the Canary Current at 21°N and 26°N from the eu- and mesotrophic upwelling zone off Northwest Africa to the oligotrophic central gyre waters. Migrant biomass was estimated by sampling during day and night using a Longhurst-Hardy Plankton Recorder (LHPR) net in the 0–900 m depth water column. The electron transfer system (ETS) enzymatic activity was measured as a proxy for zooplankton respiration in the 0–900 m depth water column. Respiratory flux was obtained from the migrant biomass and the daytime respiration in the 200–800 m layer, assumed as the residence depth of migrant zooplankton. The southern transect at 21°N showed higher primary production, zooplankton biomass, migrant biomass, and lower passive flux. Zooplankton respiratory flux varied from 2.8 to 88.3% of the POC flux, being lower in the northern (5.3% ±2.7) than in the southern transect (46.1% ±32.9). Migrant biomass was significantly correlated to primary production (r2 = 0.570, p

The Canary current upwelling is one of the major eastern boundary coastal upwelling systems in the world, bearing a high productive ecosystem and commercially important fisheries. The Canary current upwelling system (CCUS) has a large latitudinal extension, usually divided into upwelling zones with different characteristics. Eddies, filaments and other mesoscale processes are known to have an impact in the upwelling productivity, thus for a proper representation of the CCUS and high horizontal resolution are required. Here we assess the CCUS present climate in the atmosphere-ocean regionally coupled model. The regional coupled model presents a global oceanic component with increased horizontal resolution along the northwestern African coast, and its performance over the CCUS is assessed against relevant reanalysis data sets and compared with an ensemble of global climate models (GCMs) and an ensemble of atmosphere-only regional climate models (RCMs) in order to assess the role of the horizontal resolution. The coupled system reproduces the larger scale pattern of the CCUS and its latitudinal and seasonal variability over the coastal band, improving the GCMs outputs. Moreover, it shows a performance comparable to the ensemble of RCMs in representing the coastal wind stress and near-surface air temperature fields, showing the impact of the higher resolution and coupling for CCUS climate modelling. The model is able of properly reproducing mesoscale structures, being able to simulate the upwelling filaments events off Cape Ghir, which are not well represented in most of GCMs. Our results stress the ability of the regionally coupled model to reproduce the larger scale as well as mesoscale processes over the CCUS, opening the possibility to evaluate the climate change signal there with increased confidence., Open Access funding enabled and organized by Projekt DEAL. Ruben Vazquez was supported through a doctoral grant at the University of Ferrara and University of Cadiz. Dmitry Sein was supported in the framework of the state assignment of the Ministry of Science and Higher Education of Russia (No. 0128-2021-0014). This work used resources of the Deutsches Klimarechenzentrum (DKRZ) granted by its Scientific Steering Committee (WLA) under project ID ba0987.

The dynamics of the subtropical pelagic ecosystems of the Northeast Atlantic are still poorly known due to the high costs associated with sampling large oceanic areas. Top predators can be used as alternative low-cost samplers and indicators of the temporal variability of such systems. To study the variation in the composition of pelagic species through time in the broad Canary current region, we analysed foraging trips and regurgitations of Cory's shearwaters Calonectris borealis nesting on Selvagens islands, in 2008-2011 and 2016-2018. Fisheries data, oceanographic variables and the North Atlantic Oscillation were explored as possible explanatory variables for trends in behaviour and diet. Cory's shearwaters' diet, complemented by fisheries data, revealed marked changes in the composition of the pelagic fish communities. In 2016 there was a peak in the abundance of the Atlantic chub mackerel Scomber colias, followed by an explosive increase in the abundance of the Longspine snipefish Macroramphosus scolopax in 2017 and 2018, as deduced from the diet composition of the Cory's shearwater, and supported by fisheries data, in the broad oceanic area surrounding the Selvagens islands. Oceanographic variables did not show fluctuations correlated with these marked shifts in pelagic fish availability, the causes of which remain largely unknown. This study highlights the importance of the Atlantic chub mackerel and of the Longspine snipefish in the Madeira/Canary region and exemplifies the efficiency of avian predators in revealing rapid changes in pelagic communities of oceanic domains. Such trends and variations need to be better monitored and understood to measure the impact of ongoing global changes and to sustainably manage the marine environment and resources. Fundação para a Ciência e Tecnologia - FCT info:eu-repo/semantics/publishedVersion

Eastern Boundary Upwelling Ecosystems (EBUEs) are associated with high biological productivity, high fish catch and they highly contribute to marine carbon sequestration. Whether coastal upwelling has intensified or weakened under climate change in the past decades is controversially discussed and different approaches (e.g., time-series of chlorophyll, wind, sea surface temperature, modeling experiments) have been considered. We present a record of almost two decades of particle fluxes (1991–2009) from ca. 600 to 3100 m water depth in the Canary Basin at site ESTOC (European Station for Time series in the Ocean Canary Islands; ca. 29°N, 15°30.W, ca. 3600 m water depth), located in the offshore transition zone of the northern Canary Current-EBUE. We compare these flux records with those measured at a mesotrophic sediment trap site further south off Cape Blanc (Mauritania, ca. 21°N). The deep ocean fluxes at ESTOC in ca. 3 km recorded the evolution of the coastal Cape Ghir filament (30–32°N, 10–12°W) due to lateral advection of particles, whereas the upper water column sediment traps in ca. 1 km reflected the oligotrophic conditions in the overlying waters of ESTOC. We observed an increased emphasis in spring-time fluxes since 2005, associated with a change in particle composition, while satellite chlorophyll biomass did not show this pattern. Due to its northern location in the CC-EBUEs, spring biogenic fluxes at ESTOC provide a better relationship to the forcing of the North Atlantic Oscillation than those recorded further south off Cape Blanc. Off Cape Blanc, deep fluxes showed the best overlap with the deep ESTOC fluxes during the spring season before 2005. On the long-term, both chlorophyll and particle fluxes showed an increasing trend at ESTOC which was not observed further south at the mesotrophic Cape Blanc site. This might indicate that, depending on their location along the NW African margin, coastal upwelling systems react differently to global change.

International audience; The Canary Islands, east of the North Atlantic Ocean (27°N-29°N), are under the influence of the Canary Current, the descending branch of the North Atlantic Gyre, which is modulated by coastal upwelling off NorthWest Africa. They constitute strategic sites for palaeoclimatic reconstructions, especially for the Last Interglacial (LIG, 129 to 116 ky BP) estimated to be warmer than present. Seventy-four carbon and oxygen isotope bulk analyses and time series measurements were performed on 32 aragonitic mollusc shells from the LIG marine deposits on Lanzarote and Fuerteventura islands during a period of sea-level highstand that we estimated to occur between 125 and 119-116 ky BP. Our SST calculations, inferred from shell  18 O values using available isotopic fractionation equations, provide a seasonal SST amplitude ranging from 3.5°C to 6.0°C, in agreement with the modern seasonal amplitude, along with a mean SST comprised between 20.41.3°C and 22.21.2°C. With respect to the pre-industrial times, we deduce a positive SST anomaly in the range of +1.01.4°C to +2.81.3°C, consistent with the presence of the species Persististrombus latus, typical of warm SSTs. Although this finding does not match with the zonal negative anomaly of a reconstructed SST at low latitudes of the North Atlantic, it is nevertheless corroborated by other climate reconstructions in the northeastern tropical Atlantic region. We attribute this trend to an excess of summer insolation during the LIG which warmed the Canary Current, enhanced by a weakening of the North African upwelling. The entire North Atlantic Gyre was probably warmer during the LIG.

Eastern boundary upwelling provides the conditions for high marine productivity in the Canary Current System off NW-Africa. Despite its considerable importance to fisheries, knowledge on this marine ecosystem is only limited. Here, parasites were used as indicators to gain insight into the host ecology and food web of two pelagic fish species, the commercially important species Trichiurus lepturus Linnaeus, 1758, and Nealotus tripes Johnson, 1865. Fish specimens of T. lepturus (n = 104) and N. tripes (n = 91), sampled from the Canary Current System off the Senegalese coast and Cape Verde Islands, were examined, collecting data on their biometrics, diet and parasitisation. In this study, the first parasitological data on N. tripes are presented. T. lepturus mainly preyed on small pelagic Crustacea and the diet of N. tripes was dominated by small mesopelagic Teleostei. Both host species were infested by mostly generalist parasites. The parasite fauna of T. lepturus consisted of at least nine different species belonging to six taxonomic groups, with a less diverse fauna of ectoparasites and cestodes in comparison to studies in other coastal ecosystems (Brazil Current and Kuriosho Current). The zoonotic nematode Anisakis pegreffii occurred in 23% of the samples and could pose a risk regarding food safety. The parasite fauna of N. tripes was composed of at least thirteen species from seven different taxonomic groups. Its most common parasites were digenean ovigerous metacercariae, larval cestodes and a monogenean species (Diclidophoridae). The observed patterns of parasitisation in both host species indicate their trophic relationships and are typical for mesopredators from the subtropical epi- and mesopelagic. The parasite fauna, containing few dominant species with a high abundance, represents the typical species composition of an eastern boundary upwelling ecosystem.

This is a summary of the paper "The Canary Deep Poleward Undercurrent" for the EuroArgo platform in order to show the possible uses of data from ARGO profilers by the scientific community. The original authors are contained in the review. This study reports the first direct observations of the continuity of the deep poleward flow of the Canary Deep Poleward Undercurrent (CdPU) in the North-Africa sector of the Canary Current Eastern Boundary upwelling system (CanCEBS), and one of the few direct observations in the North-Africa sector of the Canary Current eastern boundary. The results from the measurements reported by Argo floats indicate that the Canary Island archipelago disrupts the deep poleward undercurrent even at depths where the flow is not blocked by the bathymetry. The deep poleward undercurrent flows west around the eastern-most islands and north east of the Conception Bank to rejoin the intermittent branch that follows the African slope in the Lanzarote Passage.

The Canary Islands are immersed in the eastern boundary of the subtropical gyre, in the coastal transition zone of the Canary Current Eastern Boundary Current. They are an ideal place for the study of the variability of the subtropical gyre. With this background, in 2006 the Spanish Institute of Oceanography (IEO) began an observational program around the Canary Islands, known as the Raprocan (deep hydrographic section of the Canary Islands), in order to establish the scales of variability in the range decadal/subdecadal in the subtropical gyre. Raprocan consists in hydrographic cruises in two seasons, with 50 hydrographic stations around the Canary archipelago. The use of Gliders for oceanographic studies has been demonstrated to be a valuable tool to understand the dynamic regimes at the area and it complements studies based in cruise hydrographic data. The large meaningful applications that offer these devices ranges from quantification of heat exchange between atmosphere – ocean, mass transport quantification, water masses identification, primary productivity quantification of the upwelling area and seasonal variability studies, among others. In this context, the Spanish Institute of Oceanography (IEO) and the Canary Islands Oceanic Platform (PLOCAN) developed a join program to set up glider missions to complement Raprocan. Here we describe the program and its results.

The Atlantic meridional overturning circulation (AMOC) is recognized as an important component of the climate system, contributing to the relatively mild climate of northwest Europe. Due to its importance, the strength of the AMOC is continually monitored along 26oN with several moorings, east of the Bahamas, in the Middle Atlantic Ridge and south of the Canary islands, known as the RAPID array. The measurements of the RAPID array show a 6 Sv seasonal cycle for the AMOC, and recent studies have pointed out the dynamics of the eastern Atlantic as the main driver for this seasonal cycle, specifically, rossby waves excited south of the Canary Islands.Due to the important role of the eastern Atlantic, in this study we describe the seasonal cycle of the Canary Current (CC) and the Canary Upwelling Current (CUC), using hydrographic data from two cruises carried out in a box around the Canary Islands, the region where the eastern component of the RAPID array is placed. CTD, VMADCP and LADCP data were combined with inverse modeling in order to determine absolute geostrophic transports in the Canary Islands region in fall and spring. During spring, the overall transport of Canary Current and the CUC was southward. In the Lanzarote Passage (LP), between the Canary Islands and Africa, the CUC transported 0.6±0.20 Sv southward, while the Canary Current transported 1.0±0.40 Sv in the oceanic waters of the Canary Islands Archipelago. During fall, the CUC transported 2.8±0.4Sv northward, while the CC transported 2.9±0.60 Sv southward in the oceanic waters of the Canary Islands Archipelago. The seasonal cycle observed has and amplitude of 3.4Sv for the CUC and 1.9Sv for the CC. Data from a mooring in the LP and the hydrographic data was used to calibrate geostrophic transport estimated using altimetry data. The amplitude of the seasonal cycle of the geostrophic transport obtained using the calibrated altimetry data (Figure 1) was quite similar to the seasonal cycle of the Eastern Atlantic contribution to the AMOC, as measured by the RAPID array. To understand the relationship between the seasonal cycle found in the CC and CUC, and the amplitude of the seasonal cycle of the AMOC transport associated with Rossby waves, a sensitivity study of the Rossby wave model is included.

The Canary Upwelling System (CUS), a major eastern boundary upwelling system, sustains large cross-border fisheries of small pelagic fish, which poses the question of stock connectivity. Studies suggest that ichthyoplankton transport from the northwest African coast to the Canary Islands (Cl) is facilitated by coastal-upwelling associated filaments. Here we analyze connections between larval supply to the Cl and sardine and anchovy populations that spawn over the continental shelf. For both species, ichthyoplankton observations (1) at the shelf and (2) near the island of Gran Canaria (GC) are used. Predictions of ichthyoplankton transport to GC are obtained from the Ichthyop Lagrangian transport model, which is forced by a high-resolution hydrodynamic model (ROMS) that reproduces the regional circulation. Results show that upwelling filaments play an important role in the transport of larvae to GC. However, (1) filaments are not the only mechanism, and (2) filament presence does not necessarily imply larval transport. Anchovy and sardine larval presence at GC appears to be independent of the respective adult spawning seasonality. Combining of observed and modeled data does not succeed in reproducing the observed larval patterns at GC. Various hypotheses are proposed to explain this discrepancy in larval transport to (C) 2011 Elsevier B.V. All rights reserved.

In a hierarchy of increasing complexity of physical forcing mechanisms, we conduct a process-oriented study of the Northern Canary Current System (NCCS) with a terrain-following numerical ocean model (in this case the Princeton Ocean Model, POM) to investigate the forcing mechanisms for the classical as well as unique features of the NCCS. While most of the NCCS features are realistically simulated, a key comparison of the results shows that unexpectedly a realistic subsurface mesoscale feature is simulated in a flat bottom NCCS model but not in the same model with bottom topography. We then show that this is a consequence of a numerical choice, which leads to the use of an improved technique to smooth the bottom topography, which better preserves the raw topography and subsequently is shown to produce the subsurface feature. This choice is then used in the final and most realistic of the NCCS experiments, in which a high temporal resolution study is conducted from March to September 1996 for the NCCS coastal ocean domain using daily winds and thermohaline forcing initialized on 2 March 1996 from a one-way coupled North Atlantic Parallel Ocean Program (POP) model updated at the lateral boundaries of the POM model every three days. A key physical result is that a dynamic flow consistent with the Azores Current is produced in this experiment, a feature not produced in the other experiments which used climatological data at the open boundaries. The results of these process-oriented experiments emphasize that numerical models of ocean circulation require important choices, which are both numerical and physical.

15 pages, 5 figures, 5 tables, Aim. Apical pelagic species forage in predictable habitats, and their movements should signal biologically and ecologically significant areas of the marine ecosystem. Several countries are now engaged in identifying these areas based on animal tracking, but this is often limited to a few individuals from one breeding population, which may result in biased portrayals of the key marine habitats. To help identify such foraging areas, we compiled tracking data of a marine top predator from the main breeding colonies in the Central Macaronesia. Location. North-east Atlantic Ocean. Methods. Over seven years, we tracked the foraging movements of Cory's shearwaters (Calonectris borealis) from several populations during the chick-rearing period using global positioning system and platform terminal transmitter devices. Results. We obtained foraging trips from 174 shearwaters breeding on six important colonies representative of the range occupied in the Macaronesian Archipelagos of Madeira, Salvages and Canaries. Our results show that birds orient and move rapidly towards the closest neritic waters over the African continental shelf. Birds from different colonies show substantial spatial segregation in their foraging grounds but consistently overlap in some specific foraging areas along the Canary Current characterized by high productivity. By weighting the use of foraging grounds according to the size of each study population, we inferred the overall exploitation of such areas. Main conclusions. Our meta-population approach provides a more comprehensive picture of space use from both perspectives: the studied species and the Canary Current system. Foraging grounds consistently used by several populations may not be adequately identified by tracking a single population, and therefore, multiple population tracking studies are needed to properly delineate key conservation areas and inform conservation planning in the marine ecosystem. Finally, we highlight the long-term stability and sustainability of identified foraging areas and propose that countries with geographical jurisdictions over the Canary Current area should work towards multilateral agreements to set management plans for this key marine ecosystem, We are thankful to A. Almeida, H. Alonso, M. N. Carrasco, T. Catry, M.P. Dias, L. Gangoso, M. Lecoq, J. M. Mart ínez, R. Mart ínez, A. Padr on, J. Prieto, A. Rodr íguez, T. Militão, X. Moreno, M. L opez, J. Ferrer, L. Est evez and C. Canella for their field and logistic support. Parque Natural da Madeira and several Cabildos Insulares provided permissions and logistical support. We are also indebted with E. Batllori for helping with spatial modelling and M. Brooke for reviewing an earlier manuscript. RR, JN, VHP and JMR-G were supported by respective programmes of Beatriu de Pin os (2010-BP_A-00173), Juan de la Cierva (JCI-2009-05426), Fundac ~ao para a Ciência e Tecnologia (FCT; SFRH/BPD/63825/2009) and Formaci on de Profesorado Universitario (FPU; AP2009-2163). This study was financed by European Union (EU), the Spanish Ministerio de Educaci on y Ciencia (MEyC) and the Portuguese FCT through different projects: LIFE04NAT/ES/000049(EU), LIFE04NAT/PT/000213(EU), LIFE07NAT/E/000732(EU), LIFE09NAT/PT/000041(EU), REN2002-01164(MEyC), CGL2006-01315/BOS(MEyC), CGL2009-11278/BOS(MEyC), PTDC/MAR/71927/2006(FCT) and PEst-OE/MAR/UI0331/2011(FCT)

The regional ocean circulation within the Canary Upwelling System between 31°N and 35°N is studied using numerical tools. Seasonal mean and near-instantaneous velocity fields from a previously-generated climatological Regional Ocean Modelling System (ROMS) solution of the Canary Basin are used to force a series of offline Lagrangian particle-tracking experiments. The primary objective is to identify the pathways through which water parcels arrive at the upwelling region north of Cape Ghir. Examining year-long pathways, the Azores Current contributes over 80% of particles annually, of which a large proportion arrive directly from offshore (from the northwest), while others travel along the shelf and slope from the Gulf of Cadiz. The remaining ~20% originate within the Gulf of Cadiz or come from the south, although the southern contribution is only significant in autumn and winter. When season-long pathways are considered, the alongshore contributions become increasingly important: northern contributions reach 40% in spring and summer, while southern values exceed 35% in winter. This study also shows that coastal upwelling changes both spatially and temporally. Upwelling becomes intensified near Cape Beddouza, with most upwelling occurring within ~40 km from shore although significant values may reach as far as 120 km offshore north of Cape Beddouza; at these locations the offshore integrated upwelling reaches as much as 4 times the offshore Ekman transport. In the Cape Beddouza area (32°N to 33°N), upwelling is negligible in February but intensifies in autumn, reaching as much as 3 times the offshore Ekman transport., Se estudia la circulación oceánica regional en el Sistema de Afloramiento de Canarias entre 31 y 35°N mediante herramientas numéricas. Con este fin se realizan una serie de experimentos de seguimientos de partículas Lagrangianas mediante los campos de velocidad, tanto los medios estacionales como los cuasi-instantáneos, obtenidos a partir de una solución previamente generada del Sistema de Modelado Oceánico Regional (ROMS). El objetivo principal es identificar las rutas mediante las cuales las parcelas de agua llegan a la región de afloramiento al norte de Cabo Ghir. Al examinar las rutas anuales se aprecia que la Corriente de Azores contribuye con más del 80% de las partículas, una gran proporción de las cuales llega directamente desde costa afuera (desde el noroeste) mientras que otras siguen la plataforma y el talud continental desde el Golfo de Cádiz. Las restantes ~20% se originan en el Golfo de Cádiz o vienen desde el sur, aunque la contribución sureña solo es significativa en otoño e invierno. Al examinar las rutas estacionales se observa que las contribuciones a lo largo de la costa se tornan más importantes: la contribución norteña alcanza el 40% en primavera y verano mientras que las partículas originadas al sur exceden un 35% en invierno. Este estudio también muestra que el afloramiento costero cambia temporal y espacialmente. El afloramiento se intensifica cerca de Cabo Beddouza, con la mayor parte del afloramiento teniendo lugar en unos ~40 km desde la costa, aunque se obtienen valores significativos a distancias de hasta 120 km fuera de costa al norte de Cabo Beddouza; en estas mismas localidades el afloramiento integrado costa afuera alcanza hasta 4 veces el transporte de Ekman perpendicular a costa. En el área de Cabo Beddouza (32 a 33°N), el afloramiento es despreciable en febrero pero se intensifica en otoño, alcanzando hasta 3 veces el transporte de Ekman perpendicular a costa.

Plastic ingestion by adult Procellariiformes has been widely recorded, but few studies have evaluated intergenerational transfer. We assessed the prevalence of plastic particles, as well as their basic character- istics, in the gut content of dead Cory’s shearwater fledglings stranded by light pollution on Canary Islands. Eighty-three percent of birds were affected, containing on average 8.0 plastic pieces per bird. The average plastic weight per bird was low (2.97 ± 3.97 mg) compared with other petrel species. We found no rela- tionships between plastic loads and body condition or body size, but negative effects may be hidden or delayed. We propose to use the fledglings stranded by light pollution to carry out more precise studies to understand the potential hidden costs of plastic ingestion; and to monitor in a long-term the marine debris to develop management actions for the control of pollution at the marine environment

Special volume: Advances in Spanish physical oceanography. Scientia Marina 76(Suppl.1) 2012.-- 16 pages, 10 figures, 1 table, [EN] The regional ocean circulation within the Canary Upwelling System between 31°N and 35°N is studied using numerical tools. Seasonal mean and near-instantaneous velocity fields from a previously-generated climatological Regional Ocean Modelling System (ROMS) solution of the Canary Basin are used to force a series of offline Lagrangian particle-tracking experiments. The primary objective is to identify the pathways through which water parcels arrive at the upwelling region north of Cape Ghir. Examining year-long pathways, the Azores Current contributes over 80% of particles annually, of which a large proportion arrive directly from offshore (from the northwest), while others travel along the shelf and slope from the Gulf of Cadiz. The remaining ~20% originate within the Gulf of Cadiz or come from the south, although the southern contribution is only significant in autumn and winter. When season-long pathways are considered, the alongshore contributions become increasingly important: northern contributions reach 40% in spring and summer, while southern values exceed 35% in winter. This study also shows that coastal upwelling changes both spatially and temporally. Upwelling becomes intensified near Cape Beddouza, with most upwelling occurring within ~40 km from shore although significant values may reach as far as 120 km offshore north of Cape Beddouza; at these locations the offshore integrated upwelling reaches as much as 4 times the offshore Ekman transport. In the Cape Beddouza area (32°N to 33°N), upwelling is negligible in February but intensifies in autumn, reaching as much as 3 times the offshore Ekman transport, [ES] Se estudia la circulación oceánica regional en el Sistema de Afloramiento de Canarias entre 31 y 35°N mediante herramientas numéricas. Con este fin se realizan una serie de experimentos de seguimientos de partículas Lagrangianas mediante los campos de velocidad, tanto los medios estacionales como los cuasi-instantáneos, obtenidos a partir de una solución previamente generada del Sistema de Modelado Oceánico Regional (ROMS). El objetivo principal es identificar las rutas mediante las cuales las parcelas de agua llegan a la región de afloramiento al norte de Cabo Ghir. Al examinar las rutas anuales se aprecia que la Corriente de Azores contribuye con más del 80% de las partículas, una gran proporción de las cuales llega directamente desde costa afuera (desde el noroeste) mientras que otras siguen la plataforma y el talud continental desde el Golfo de Cádiz. Las restantes ~20% se originan en el Golfo de Cádiz o vienen desde el sur, aunque la contribución sureña solo es significativa en otoño e invierno. Al examinar las rutas estacionales se observa que las contribuciones a lo largo de la costa se tornan más importantes: la contribución norteña alcanza el 40% en primavera y verano mientras que las partículas originadas al sur exceden un 35% en invierno. Este estudio también muestra que el afloramiento costero cambia temporal y espacialmente. El afloramiento se intensifica cerca de Cabo Beddouza, con la mayor parte del afloramiento teniendo lugar en unos ~40 km desde la costa, aunque se obtienen valores significativos a distancias de hasta 120 km fuera de costa al norte de Cabo Beddouza; en estas mismas localidades el afloramiento integrado costa afuera alcanza hasta 4 veces el transporte de Ekman perpendicular a costa. En el área de Cabo Beddouza (32 a 33°N), el afloramiento es despreciable en febrero pero se intensifica en otoño, alcanzando hasta 3 veces el transporte de Ekman perpendicular a costa, This research was supported by the Spanish government through projects MOC2 (CTM2008-06438-C02-01) and TIC-MOC (CTM2011-28867)

32 pages, 22 pages, 9 tables, Ocean studies in the 1970s provided an improved knowledge of the coastal upwelling region off NW Africa while in the 1980s and 1990s they led to a good description of the open ocean flow patterns in the Canary Basin. It was not until the late 1990s that major research addressed the open-coastal ocean coupled response. Here we examine the mean and seasonal circulation patterns in the Canary Basin with data from four hydrographic cruises carried out in the region between Cape Ghir, Madeira Island, and the Canary Islands. We apply an inverse box model to an ocean divided into 14 layers, with several layers representing each water mass or stratum, to obtain mass fluxes consistent with the thermal wind equation. An optimum flow description is obtained using conservation of mass, salt and heat anomaly, biologically corrected oxygen, and silicate, and allowing for Ekman transport in the surface layer and dianeutral mixing between adjacent layers. The deep waters show no predominant flow direction while the intermediate waters display localized southward flowing Mediterranean Water far from shore, and northward flowing Antarctic Intermediate Water near the continental slope, specially in the passage between the eastern Canary Islands and the African slope. The mean upper-thermocline Canary Current, composed of North Atlantic Central Water, flows south with an open-ocean branch transporting about 3 ± 1 Sv (1 Sv = 106 m3 s−1 congruent with 109 kg s−1), and an upwelling-related branch near the continental slope carrying 1 ± 0.3 Sv. The seasonal transport by the open-ocean branch intensifies and moves offshore from spring to fall (2.8 ± 1.2 Sv in spring, 2.9 ± 1.1 Sv in summer, and 4.5 ± 1.2 Sv in fall), while it carries its lowest southward mass flux in winter (1.7 ± 1.0 Sv), possibly as a result of a migration offshore the sampled region. Upwelling-related southward flow is present in spring and summer (1.9 ± 0.1 Sv and 2.4 ± 0.1 Sv, respectively) while in fall and winter it merges with the offshore southward branch. This westward migration allows a northward mass flux between the Canary Islands and the African coast (1.8 ± 0.1 Sv), that by winter reaches Cape Ghir (0.5 ± 0.2 Sv). Seasonal air–sea heat fluxes fit well with the climatological values. The net phosphate transport in the surface layer indicates that primary production was negligible in this region during January 1997 and April 1998, though in this last month production was probably starting as a result of significant nutrient supply, We acknowledge the support of the Spanish government through project CANOA (CTM2005-00444/MAR) and the European Union through projects CANIGO (MAS-CT96-0060) and OASIS (EVK3-CT-2002-00073). The first author thanks the Dirección General de Universidades e Investigación del Gobierno de Canarias for the grant received during his Ph.D

13 pages, 8 figures, 2 tables., The Canary Current (CC) is characterised by strong disruption of its flow by the Canaries Archipelago, which extends across the prevailing flow. In the Coastal Transition Zone (CTZ) downstream of the islands, a region of high mesoscale activity connects the eutrophic waters of the NW Africa coastal upwelling (UW) system with the oligotrophic open ocean waters of the eastern subtropical North Atlantic gyre (ESNA). We studied the distribution of particulate (POC) and dissolved organic carbon (DOC) and carbon remineralization rates in the 0 to 1000 m water column of this transitional region to assess its role in horizontal and vertical export of organic matter. The epipelagic waters (0 to 200 m) of the CTZ are characterised by higher mean surface integrated concentrations of POC (0.8 ± 0.4 mol C m-2) and DOC (17 ± 7 mol C m-2), and by higher community respiration (R >100 mmol C m-2 d-1) than the ESNA or UW waters. Integrated R was much lower (7 ± 3 mmol C m-2 d-1) in the mesopelagic zone (200 to 1000 m), indicating that most of the organic matter was respired in the upper 200 m, with little being transported downwards. Nevertheless, peaks in DOC and R were observed at 300 to 600 m depth, coinciding with the depth of the deep scattering layer. These relative maxima were particularly important in the case of DOC, reaching concentrations comparable to surface waters (>80 μM). In spite of this, DOC contributed only 26.5% to the apparent oxygen utilisation (AOU) in the mesopelagic zone. Correlations between R and particulate- and dissolved organic matter suggest that respiration was mainly supported by particulate material at surface and deep waters. We compared plankton metabolic balances along the UW, CTZ and ESNA. Our analyses show that during summer time, and probably during most of the year, the ESNA and CTZ behave as net heterotrophic regions. In spite of a relatively high primary production (P) favoured by mesoscale activity in the CTZ, plankton R clearly exceeds P as result of the excess carbon advected from the coastal UW. However, a significant amount of non-respired carbon must be transported from the CTZ to the open ocean to account for part of the surface metabolic imbalance between P and R reported for the ESNA., This work has been supported through the European Union (project CANIGO, MAS3.CT96-0060) and the Spanish government (project COCA, REN2000-U471-CO2-02-MAR). We thank the officers and crew of the ‘BIO Hespérides’ as well as the staff of the Unidad de Técnología Marina (Consejo Superior de Investigaciones Científicas) for their invaluable help at sea.

Seasonal and interannual variability of the Canary Current on its passage through the Canary archipelago and between 20-35°N and 10-20°N are studied with long series of historical tide gauge, sea surface temperature and hydrographic data. The variability of winds is more seasonal in the north of the area, where they are weak and perpendicular to the coast in winter, than in the south, where winds are roughly parallel to shore all year though strongest in summer. Temperature and salinity data maps show a curved structure indicative of the subtropical gyre, which varies seasonally from North to South and from the open ocean to the coast. Dynamic height analyses show this seasonal variation of the gyre to depths of 200 m and indicate the existence of a meander-like diversion around the Canary Islands. The sea level in the Canary Islands also indicates a strong seasonal variation of the north Atlantic subtropical gyre. The southward geostrophic surface flow, derived from sea surface slope, was strongest during spring and summer at the eastern islands while it was strongest in winter at the outermost islands. The spatially averaged flow between the innermost and outermost islands shows the strongest southward flow in winter. Interannual variation of the flow between these islands, investigated during two periods, 1950-1956 and 1960-1973, reveals a mainly southward flow, although several show a northward tendency. The maximum equatorward velocity of the current in both periods is around 5 cm s-1, indicating a weak current., No disponible

The flow pattern of the North Atlantic Subtropical Gyre (NASG) is simulated using a highly idealised one-layer quasi-geostrophic wind-driven model. The novel feature of the model is the specification of the eastern boundary conditions. This is an upwelling favourable region with a quasi-permanent southward flowing coastal jet, which is fed by the eastern branch of the Canary Current. The corresponding boundary conditions are non-zero normal flux and constant potential vorticity, the latter being consistent with the generation of anticyclonic vorticity by the coastal jet. We examine the sensitivity of the model to the eastern boundary conditions and compare the results with recent observations for the region, This work was supported by the European Union through project CANIGO (MAS3-CT96-1893) and the Spanish government trhough projects FRENTES (AMB95-0731) and TALUD (MAR96-1893)

Funded by Naval Postgraduate School A process-oriented study of time-dependent wind forcing is conducted using a ten-layer (B)-plane, positive ocean model to provide insight into mesoscale eddy generation and duration off the west coast of Portugal from 1987 to 1988. The wind forcing used was derived from synoptic surface pressure analyses off Lisbon, Portugal. Results obtained show that eddies generated during the coastal upwelling season (generally occurring during the spring and summer) decay during the winter. Only cyclonic eddies form during the 1987 and 1988 upwelling seasons. The eddies are generated through a combination of barotropic and baroclinic instability mechanisms. Since the wind forcing of the five-month long 1987 upwelling season, eddy characteristics appear to be more influenced by the characteristics (e.g., intensity, duration and frequency of occurrence) of the wind forcing than by the total length of the upwelling season. This study affirms the importance of wind stress forcing to the overall surface circulation and eddy generation in the coastal regime off the west coast of Portugal. Office of Naval Research; O & MN, Direct funding The work reported herein was prepared for the Office of Naval Research and funded by Naval Postgraduate School. http://archive.org/details/anumericalstudyo1094528410 The work reported herein was prepared for the Office of Naval Research and funded by Naval Postgraduate School. Lieutenant, United States Navy Approved for public release; distribution is unlimited.

A coupled physical-biogeochemical model (ROMS-PISCES) forced by climatological fields is used to examine the role of upwelling filaments in the offshore exchange of particulate (POC) and dissolved (DOC) organic carbon in the Canary Current eastern boundary upwelling system (CanC EBUS). In this region, mesoscale filaments at Capes Ghir ( °N) and Juby ( °N) have been frequently described using both observational and numerical data. Due to their semi-permanent presence and unique dynamical characteristics, studies focusing on filaments often provide an incomplete picture of the physical and biological processes at work, and their effects on coast-to-ocean export. The present model experiment confirms the complex three-dimensional structure of the filaments that comprises both offshore and onshore flow components. The model shows strong seasonal variability in the offshore transport mediated by the filaments. Recirculation at the edges of the filaments returns water towards the shore, especially in autumn when they are diverted northwards by the large scale boundary circulation. By contrast, offshore transport peaks during late spring - early summer when onshore recirculation is limited. Overall, the estimated net annual offshore flux of excess total organic carbon (e-TOC, the non-refractory pools of DOC and POC) averages 2.0 kg C y−1, and may increase up to 4.3 kg C y−1 during the peak upwelling season, each filament contributing to export of up to 22.6% of the organic carbon within the first 100 km from shore along the CanC EBUS (between 9.5 and 32 ° N). These results strongly support the inclusion of offshore transport estimates by coastal filaments in regional carbon budgets., This research was supported by projects CAIBEX (CTM2007-66408-CO2-02) and FLUXES (CTM2015- 69392-C3-1-R) funded by the ‘Spanish Plan Nacional de I + D’, and by projects SUMMER (AMD-817806-5) and TRIATLAS (AMD-817578-5) financed by the 'European Commission' to JA. EM acknowledges support from the Spanish Research Agency and the European Regional Development Fund (Award no. CTM2016-78607-P).