A suitable sampling technology to identify species and to estimate population dynamics based on individual counts at different temporal levels in relation to habitat variations is increasingly important for fishery management and biodiversity studies. In the past two decades, as interest in exploring the oceans for valuable resources and in protecting these resources from overexploitation have grown, the number of cabled (permanent) submarine multiparametric platforms with video stations has increased. Prior to the development of seafloor observatories, the majority of autonomous stations were battery powered and stored data locally. The recently installed low-cost, multiparametric, expandable, cabled coastal Seafloor Observatory (OBSEA), located 4 km off of Vilanova i la Gertrú, Barcelona, at a depth of 20 m, is directly connected to a ground station by a telecommunication cable; thus, it is not affected by the limitations associated with previous observation technologies. OBSEA is part of the European Multidisciplinary Seafloor Observatory (EMSO) infrastructure, and its activities are included among the Network of Excellence of the European Seas Observatory NETwork (ESONET). OBSEA enables remote, long-term, and continuous surveys of the local ecosystem by acquiring synchronous multiparametric habitat data and bio-data with the following sensors: Conductivity-Temperature-Depth (CTD) sensors for salinity, temperature, and pressure; Acoustic Doppler Current Profilers (ADCP) for current speed and direction, including a turbidity meter and a fluorometer (for the determination of chlorophyll concentration); a hydrophone; a seismometer; and finally, a video camera for automated image analysis in relation to species classification and tracking. Images can be monitored in real time, and all data can be stored for future studies. In this article, the various components of OBSEA are described, including its hardware (the sensors and the network of marine and land nodes), software (data acquisition, transmission, processing, and storage), and multiparametric measurement (habitat and bio-data time series) capabilities. A one-month multiparametric survey of habitat parameters was conducted during 2009 and 2010 to demonstrate these functions. An automated video image analysis protocol was also developed for fish counting in the water column, a method that can be used with cabled coastal observatories working with still images. Finally, bio-data time series were coupled with data from other oceanographic sensors to demonstrate the utility of OBSEA in studies of ecosystem dynamics.

The rhythmic behavior of marine species generates uncertainties in population and biodiversity assessments if the frequency of sampling is too low and irregular over time. Few attempts have been made to link community changes to the rhythmic behavior of individuals within populations. Cabled video observatories can be used to explore community changes over different temporal windows as a result of the activity rhythms of individuals within populations. In this study, we used, for the first time, a coastal cabled observatory (OBSEA) to video monitor activity rhythms of different fish species within an artificial reef area at a high frequency. During 1 mo, 30 min daily count patterns were continuously measured and compared with the corresponding solar irradiance. A significant (p < 0.05) day-night patterning was observed in the majority of recognized taxa by Chi-Square periodogram analysis. Three types of rhythms were identified in waveform plotting: (1) diurnal (Chromis chromis, Coris julis, Diplodus annularis, D. cervinus, D. sargus, D. vulgaris, Serranus cabrilla, Dentex dentex, Symphodus sp.); (2) nocturnal (Atherina sp. and Scorpaena sp.); and (3) crepuscular (Apogon imberbis, Oblada melanura, and Spicara maena). Diurnal species clustered around maximum averaged irradiance (computed from a cosinor analysis). The results were discussed evaluating whether visual count time series represent a reliable proxy for the swimming activity rhythms of individuals and whether the complex habitat use of coastal fishes would require the use of spatial networks of cameras. KEY WORDS:OBSEA · Cabled video observatories · Swimming rhythms · Western Mediterranean · Coastal areas · Temperate fishes · Irradiance · Daily activity Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 486: [223][224][225][226][227][228][229][230][231][232][233][234][235][236] 2013 seasons in coastal areas (Condal et al. 2012). The consideration of these aspects of activity and perceived community structure is critical in monitoring the effectiveness of marine protected areas, in improving survey designs for fisheries assessment, and in evaluating habitat use (Willis et al. 2000). To date, few attempts have been made to link temporal changes in communities to the behavioral rhythms of individuals within populations (Aguzzi et al. 2011a). Fish swimming/resting activity rhythms have traditionally been studied through laboratory experiments (re viewed by Reebs 2002, López-Olmeda & Sánchez-Vázquez 2010. Over the past few decades, however, the activity rhythms of a variety of species have also been the focus of increased study in the field based on a variety of sampling techniques subject to technical constraints on the repetition and duration of sampling. These techniques include the use of beach seines (Harmelin-Vivien & Francour 1992, Letourneur et al. 2001, Dul

Launched in 2011 within the European Metrology Research Programme (EMRP) of EURAMET, the joint research project "MeteoMet" -Metrology for Meteorology -is the largest EMRP consortium: National Metrology Institutes, Universities, meteorological and climate agencies, Research Institutes, collaborators and manufacturers are working together, developing new metrological techniques, as well as improving already existing ones, for meteorological observations and climate records. The project focuses on: humidity in the upper and surface atmosphere, air temperature, surface and deep-sea temperatures, soil moisture, salinity, permafrost temperature, precipitation and snow albedo effect on air temperature. All tasks are performed under rigorous metrological approach and include design and study of new sensors, new calibration facilities, investigation of sensors characteristics, improved techniques for measurements of Essential Climate Variables with uncertainty evaluation, traceability, laboratory proficiency and inclusion of field influencing parameters, long-lasting measurements, and campaigns in remote and extreme areas. MeteoMet vision is to make a further step towards establishing full data comparability, coherency, consistency and long-term continuity, through a comprehensive evaluation of the measurement uncertainties for the quantities involved in the global climate observing systems and the derived observations. The improvement of quality of Essential Climate Variables records, through the inclusion of measurement uncertainty budgets, will also highlight possible strategies for the reduction of the uncertainty. This contribution presents selected highlights of the MeteoMet project and reviews the main ongoing activities, tasks and deliverables, with a view to its possible future evolution and extended impact.

To adequately describe seasonal rhythms in\ud habitat utilization by fish communities, observations are\ud needed that occur at a relatively high frequency and over\ud large temporal windows. For the first time, images collected\ud from a cabled video-observatory (the western\ud Mediterranean expandable SEAfloor OBservatory; OBSEA)\ud were utilized to examine habitat utilization by coastal\ud fishes. Over the course of a year, hourly digital images of\ud the water column and an artificial reef were obtained during\ud daylight hours. For each image, the total number of\ud species, an estimate of the abundance of individuals, and\ud the Shannon Diversity Index were quantified. A total of 22\ud fish species commonly associated with nearshore western\ud Mediterranean habitats were identified, and significant\ud spatial (water column vs. artificial reef), seasonal (spring,\ud summer, autumn, and winter), and daily (morning, midday,\ud and sunset) differences in habitat utilization occurred. Four\ud species (Diplodus vulgaris, Diplodus cervinus, Diplodus\ud sargus, and Scorpaena porcus) were associated with the\ud artificial reef, while one species (Pagrus pagrus) chiefly\ud occurred in the water column. Chromis chromis and\ud Diplodus annularis occurred at the site more frequently in\ud the winter and autumn, respectively, while 14 other species\ud utilized the site more frequently in either the spring (8 spp)\ud or summer (6 spp). In addition, Dentex dentex and Spicara\ud maena occurred more frequently at sunset, while D. cervinus\ud displayed a crepuscular rhythm (occurring more\ud frequently in the morning and at sunset). Species diversity\ud was highest in the summer and lowest in the winter. If not\ud taken into account when planning in situ sampling, such\ud seasonal and/or diel differences may lead to spurious\ud estimates of population sizes and biodiversity. We suggest\ud that cabled video-observatories offer a non-invasive and\ud reliable technology for faunistic sampling and population\ud assessment in coastal water of the Mediterranean and likely\ud elsewhere.Peer ReviewedPostprint (published version

The study of the effects of climate change on the marine environment requires the existence of sufficiently long time series of key parameters. The study of these series allows both to characterize the range of variability in each particular region and to detect trends or changes that could be attributed to anthropogenic causes. For this reason, networks of permanent cabled observation systems are being deployed in the ocean. This paper presents a balance of a decade of activity at the OBSEA cabled observatory, as an example of ocean monitoring success and drawbacks. It is not the objective of this article to analyze the scientific and technical aspects already presented by the authors in different publications (Table 4). We will evaluate the overall experience by retracing the different steps of infrastructure deployment and maintenance, focusing on routines for in situ control, damages experienced, breakdowns and administrative constraints by local administrations. We will conclude by providing a set of guidelines to improve cabled observatories scientific outreach, societal projection, and economic efficiency. As a result of this work, a 10-years dataset has been published in Pangaea that is available for the community. INDEX TERMS Cabled observatories, multidisciplinary observation, coastal ocean monitoring, underwater imaging, european multidisciplinary seafloor and water column observatory (EMSO), JERICO-RI.