Stepped Coastal Water Warming Revealed by Multiparametric Monitoring at NW Mediterranean Fixed Stations.

Since 2014, the global land and sea surface temperature has scaled 0.23 °C above the decadal average (2009-2018). Reports indicate that Mediterranean Sea temperatures have been rising at faster rates than in the global ocean. Oceanographic time series of physical and biogeochemical data collected from an onboard and a multisensor mooring array in the northwestern Mediterranean Sea (Blanes submarine canyon, Balearic Sea) during 2009-2018 revealed an abrupt temperature rising since 2014, in line with regional and global warming. Since 2014, the oligotrophic conditions of the water column have intensified, with temperature increasing 0.61 °C on the surface and 0.47 °C in the whole water column in continental shelf waters. Water transparency has increased due to a decrease in turbidity anomaly of -0.1 FTU. Since 2013, inshore chlorophyll a concentration remained below the average (-0.15 mg·l-1) and silicates showed a declining trend. The mixed layer depth showed deepening in winter and remained steady in summer. The net surface heat fluxes did not show any trend linked to the local warming, probably due to the influence of incoming offshore waters produced by the interaction between the Northern Current and the submarine canyon. Present regional and global water heating pattern is increasing the stress of highly diverse coastal ecosystems at unprecedented levels, as reported by the literature. The strengthening of the oligotrophic conditions in the study area may also apply as a cautionary warning to similar coastal ecosystems around the world following the global warming trend.

Adipose tissue compartments, muscle mass, muscle fat infiltration, and coronary calcium in institutionalized frail nonagenarians.

OBJECTIVE: to compare the different adipose tissue (AT) compartments, muscle mass, muscle fat infiltration, coronary calcium, as well as associations among changes in different AT compartments between frail and robust nonagenarians. MATERIALS AND METHODS: Forty-two elderly subjects took part in this study: 29 institutionalized frail elderly (92.0 ± 8 years) and 13 robust elderly (88.2 ± 4.1 years). All patients underwent helical thoracic, abdominal and thigh computed tomography (CT). In addition, a non-enhanced prospectively ECG-triggered cardiac CT was performed to quantify the amount of coronary artery calcification and measure pericardial AT. RESULTS: The robust group presented significantly greater pericardial and abdominal AT volume, as well as greater axial and appendicular muscle size and high-density muscle tissue (greater muscle quality) than the frail group (P < 0.001), whereas no differences between groups were observed in coronary calcium. There were positive correlations between pericardial AT with visceral and subcutaneous AT values, as well as between pericardial AT and quadriceps, hamstrings, psoas and paravertebral low-density muscle tissues in the frail and robust groups (r = 0.57 to 0.91,P < 0.05). CONCLUSIONS: Robust group presented greater muscle size and quality in the axial and appendicular muscles, as well as pericardial and abdominal AT area than the frail group. KEY POINTS: • Robust nonagenarians presented more pericardial and abdominal AT volume than frail. • Frailty is associated with lower muscle size and high-density muscle tissue. • Muscle-fat infiltration shares analogous pattern of visceral and pericardial AT distribution.

Tuna Species Substitution in the Spanish Commercial Chain: A Knock-On Effect.

Intentional mislabelling of seafood is a widespread problem, particularly with high-value species like tuna. In this study we examine tuna mislabelling, deliberate species substitution, types of substitution and its impact on prices. The survey covered the commercial chain, from Merca-Barna to fishmongers and restaurants in the Spanish Autonomous Community of Catalonia. To understand the geographic extent of the problem we also sampled Merca-Madrid, Europe's biggest fish market, and Merca-Málaga for its proximity to the bluefin tuna migratory route and trap fishery. Monthly surveys were carried out over one year. The results showed a high deficiency in labelling: 75% of points of sale and 83% of restaurants did not specify the species, and in those cases the name of the species had to be asked. A total of 375 samples were analysed genetically, the largest dataset gathered in Europe so far. The identified species were Thunnus albacares, Thunnus thynnus and Thunnus obesus. Species substitution began at suppliers, with 40% of observed cases, increasing to 58% at fishmongers and 62% at restaurants. The substitution was mainly on bluefin tuna (T. thynnus), 73% of cases. At restaurants, only during the bluefin fishing season, we observed a decrease of Bluefin tuna substitution and an increase of reverse substitution revealing some illegal fishing. The effect of species substitution on species prices was relevant: T. obesus increased its price by around €12 kg-1 when it was sold as bluefin. In view of the deficiency of labelling, the abuse of generic names and the lack of the bluefin catch document, we conclude that the Spanish regulations are ineffective, highlighting the need for policy execution, and the urgent need for information campaigns to Spanish consumers.

Individual Spawning Duration of Captive Atlantic Bluefin Tuna (Thunnus thynnus) Revealed by Mitochondrial DNA Analysis of Eggs.

This study presents the first results on Atlantic bluefin tuna (Thunnus thynnus) individual spawning duration and its short-term temporal behavior. The study was based on direct measurements resulting from mtDNA analysis of the offspring of spawners held in transport cages during the 2013 spawning monitoring survey in Balearic waters. The number of females consisted of approximately 259 individuals with an average weight of 186 kg. The survey began on May 22 and ended on July 3. Spawning started on May 30 and was observed every night afterwards. The sampling of eggs for genetic monitoring was conducted for 9 days interspersed from the beginning of spawning to the end of the survey. A total of 946 eggs were analyzed and revealed 129 different haplotypes; 77 of these were not previously detected in the Mediterranean. A total of 69 haplotypes were observed in more than one spawning event and those with higher frequency lasted their maximum possible duration. The haplotypes present at the beginning of spawning were also identified at the end of the sampling, indicating a minimum spawning duration of 34 days, and individual annual fecundity was estimated at around 1290 eggs gr(-1). These results differed from those generally presumed until now and are indicative of a much higher fecundity. Females exhibited a regular spawning schedule but with the capacity to shift the spawning hour during the spawning season. These results were observed for the eastern population of Atlantic bluefin tuna and before extrapolating to the western population, their validity should be proved.

Determination of temporal spawning patterns and hatching time in response to temperature of Atlantic bluefin tuna (Thunnus thynnus) in the Western Mediterranean.

This study analysed the temporal pattern of Atlantic bluefin tuna (ABFT) spawning in the Balearic spawning ground and examined its reproductive performance after years in captivity. Furthermore, ABFT hatching time at different on-site temperatures was determined for the first time. Spawning surveys were carried out in 4 spawning seasons (2009-2012) aboard tuna transport vessels. Three groups of spawners were monitored: a captive group transported to the spawning region and monitored throughout the four spawning seasons and two wild groups caught in 2009 and 2010 which were transferred to a monitoring transport cage immediately after being caught. Surface plankton samples were collected nightly, beginning immediately after the first purse seine catches were made and concluding after spawning was observed to have ended. All groups displayed the same spawning hours, restricted between 2:00-5:00 a.m. The captive group, as they got older, shifted towards the earliest hour, suggesting an age influence on reproductive time. The onset of spawning varied annually from the end of May to the beginning of June at temperatures around 19 °C-20 °C, ending by the second week of July. The peak of spawning was consistently around the summer solstice, June 15th-30th. The results showed the negative effect of unstable oceanographic conditions in the spawning process which might influence the annual reproductive success of ABFT. The influence of temperature on hatching time was higher than that observed in other tuna species, twice as fast at 26 °C (23 h) as at 19.5 °C (49 h). Overall, this study shows the strength of the internal mechanism in ABFT that controls spawning traits. Spawning in ABFT is cyclical and highly synchronised on diel and annual scales. We consider that the timing of spawning is rather influenced by day length and its adaptive significance is discussed.

Burst feeding of Pelagia noctiluca ephyrae on Atlantic bluefin tuna (Thunnus thynnus) eggs.

This study investigates the predation of P. noctiluca ephyrae on Atlantic Bluefin tuna (ABFT) eggs under different experimental conditions. The specific factors considered in the experimental design were: a) water mix conditions to explore predation under two-dimensional (2D) and three-dimensional (3D) prey distributions, b) prey density to investigate the ingestion rate capacity, and c) incubation time to inspect gut saturation. The eggs and jellyfish ephyrae were collected during the 2012 ABFT spawning survey off Ibiza (Balearic Isl., Western Mediterranean). The results showed that the proportion of feeding ephyrae increased with size. The mean clearance rate of feeding ephyrae, 4.14 L h(-1), was the highest ever recorded for ephyrae. Under calm conditions the eggs floated at the surface (2D spatial arrangement) and the clearance rates, at low prey densities, were at least twice those under mixed conditions (3D spatial arrangement). At high prey density, clearance rate did not differ between mix conditions, probably due to the fast gut saturation, which was reached in c.a. 15 min, as revealed by time series observations of gut contents. The fast saturation of ephyrae and their slow digestion time of approximately 18 h suggest the existence of a diel feeding periodicity. We conclude that in the Western Mediterranean, P. noctiluca ephyrae are capable of predating on ABFT eggs, a highly pulsed and spatially restricted resource that potentially switches from a 3D to a 2D configuration in the absence of wind-generated turbulence. The P. noctiluca and Atlantic Bluefin tuna egg system might represent an example of a general mechanism linking pelagic and neustonic food webs.

Functional capacity, muscle fat infiltration, power output, and cognitive impairment in institutionalized frail oldest old.

This study examined the neuromuscular and functional performance differences between frail oldest old with and without mild cognitive impairment (MCI). In addition, the associations between functional capacities, muscle mass, strength, and power output of the leg muscles were also examined. Forty-three elderly men and women (91.9±4.1 years) were classified into three groups--the frail group, the frail with MCI group (frail+MCI), and the non-frail group. Strength tests were performed for upper and lower limbs. Functional tests included 5-meter habitual gait, timed up-and-go (TUG), dual task performance, balance, and rise from a chair ability. Incidence of falls was assessed using questionnaires. The thigh muscle mass and attenuation were assessed using computed tomography. There were no differences between the frail and frail+MCI groups for all the functional variables analyzed, except in the cognitive score of the TUG with verbal task, which frail showed greater performance than the frail+MCI group. Significant associations were observed between the functional performance, incidence of falls, muscle mass, strength, and power in the frail and frail+MCI groups (r=-0.73 to r=0.83, p<0.01 to p<0.05). These results suggest that the frail oldest old with and without MCI have similar functional and neuromuscular outcomes. Furthermore, the functional outcomes and incidences of falls are associated with muscle mass, strength, and power in the frail elderly population.