Desarrollo ontogénico de Acipenser Naccarii (Bonaparte 1836). Posible aplicación en acuicultura

La información sobre el desarrollo embrionario y primeros estadios de A. naccarii es muy escasa e incompleta. En este trabajo se describe por primera vez la secuencia del desarrollo embrionario desde la fecundación, a partir de huevos de A. naccaríi fecundados 'in vitro', hasta la etapa juvenil, 3 meses postfecundación. La eclosión se produjo en condiciones controladas de piscifactoría, llevadas a cabo en dos años consecutrivos (2002 y 2003) durante los meses de junio y julio, para tres cohortes reproductivas. La eclosión se produjo a los 5 días postfecundación pará una temperatura de incubación de 17 °C y a los 7 días a 15 °C (Estadios 1 - 35). El periodo de embrión de vida libre abarca desde la eclosión de los embriones basta la reabsorción de la totalidad del saco vitelínico y comienzo de la alimentación activa (Estadios 37 - 45). Mientras que para la Etapa Juvenil se han propuesto seis estadios de desarrollo (Estadios 46- 51) hasta los 3 meses post-fecundación. Para A. naccarü, se han determinado diferentes estadios en el desarrollo de A. naccarii que se engloban en tres periodos: fecundación - eclosión, que a 17°C, comprende los Estadios (1 -36) y tiene una duración deS días (120 h) a 17°C y 7 días 18 h (186 h) a 15°C; embrión de vida libre, comprende los estadios (37-45) que duras días (120 h) a 17°C y 7 días (168 h) a 15 ° C; y el desarrollo juvenil, que se extiende durante 1752 h (73 días). En conjunto el desarrollo estudiado se ha extendido durante 83 días (1992 h) a 17°C y 88 días (2106 h) a 15°C. Cada uno de los periodos en los que se ha dividido el desarrollo embrionario requiere un tiempo determinado y dentro de cada uno de ellos cada estadio transcurre también en una secuencia temporal determinada. A. naccarii, presenta un desarrollo embrionario más rápido que otros Acipenséridos, alcanzándose antes los estadios de desarrollo incluso a temperaturas más bajas. Además, para la etapa juvenil se ha descrito de forma pormenorizada la evolución de diferentes estructuras tales como aletas pares e impares, pínnulas y escudetes dorsales, laterales y ventrales. Así mismo se han realizado análisis morfométricos de la región cefálica, saco vitelínico, aletas pectorales y aleta caudal. Describimos por primera vez para un Acipensérido, la aparición de los escudetes dorsales secundarios (SD2°) que no aparecen al mismo tiempo que los primarios y se presentan en número variable y en posiciones diferentes a lo largo de la fila de escudetes dorsales. En generál, el desarrollo embrionario de los diferentes Acipenséridos es muy similar y distintos autores han defendido la similitud de los patrones de desarrollo a lo largo de este grupo (Dettlaff et al., 1993; Gisbert et al., 1998) La temperatura influye claramente en el tiempo de eclosión. El desarrollo de A. naccarii, es más rápido que la de otros esturiones incluso a menor temperatura. Se ha elaborado por primera vez para A. naccarii un modelo global que relaciona la morfogénesis a nivel macroscópico y los diferentes sistemas orgánicos, obteniéndose un mejor conocimiento sobre sus pautas de desarrollo y se establece un cronoprama de aparición de las princinales estructuras

Changes in the juvenile fish assemblage of a Mediterranean shallow Posidonia oceanica seagrass nursery area after half a century

The within-year dynamics of the juvenile fish community in a shallow seagrass-dominated nursery habitat (Posidonia oceanica) in a Mediterranean bay were compared between two surveys separated by 50 years (1960 and 2012-2013). A nocturnal survey over depths ranging from 2 to 10 m over patchy seagrass meadows was conducted for one year (2012-2013) through 72 epibenthic tows spread fortnightly in 4 nearby stations, mimicking a survey conducted in 1960 in terms of sampling intensity, sampling zone, temporal coverage and sampling gear. Although a large proportion of the fish species were similar among surveys, remarkable and statistically significant differences were detected. A striking feature was that one of the most common and abundant Sparidae species currently, Diplodus annularis, did not appear in 1960. Other strong differences included the nonappearance of the European eel Anguilla anguilla in the recent survey. Furthermore, one of the most valuable species for artisanal fisheries in the area, the black scorpionfish Scorpaena porcus, was almost 10 times less abundant in 1960. A finer-scale study of the 2012-2013 survey allowed a quantitative analysis between species composition and potential environmental drivers through redundancy analysis that well described the current pattern of time-dependent recruitment pulses in nearshore meadows of the area throughout the year, with marked effects of surface temperature and photoperiod. The comparison between surveys suggests that some major differences between surveys are not likely to be attributable to interannual stochasticity in recruitment or environmental variability but may be related to i) unaccounted-for habitat transformation and/or ii) the strong decrease in juvenile fishing mortality in this shallow nursery area since the enforcement of bans on littoral epibenthic trawling activities characteristic of this area

Effect of climatic oscillations on small pelagic fisheries and its economic profit in the Gulf of Cadiz

Several studies have shown the effect of climatic oscillations on fisheries. Small pelagic fish are of special global economic importance and very sensitive to fluctuations in the physical environment in which they live. The main goal of this study was to explore the relationship between the North Atlantic Oscillation (NAO), the East Atlantic pattern (EA), and the Arctic Oscillation (AO) on the landings and first sale prices of the most representative small pelagic commercial species of the purse-seine fisheries in the Gulf of Cadiz (North East Atlantic), the European anchovy Engraulis encrasicolus and the European sardine Sardine pilchardus. Generalised linear models (GLMs) with different data transformations and distribution errors were generated to analyse these relationships. The best results of the models were obtained by applying a moving average of order 3 to the dataset with a double weighted median. Our results demonstrate relationships between NAO, AO, and EA and European anchovy and sardine landings. These cause an indirect effect on the first sale price in markets through catch variations, which affect the price according to the law of supply and demand. The limitations of this study and management implications are discussed.Postprint2,5

A software tool for monitoring legal minimum lenght of landings: Case study of a fishery in sourthern Spain

Herramienta de interés para el control y la gestión de pesqueríasThe regulation of minimum legal size(MLS) of catches is a tool widely applied in the management of fisheries resources, although the MLS does not always coincide with the length at first maturit(LFM). The optimization of this management tool requires a series of quality control in fish markets and transportation. A software application has been developed to make the control of the landings of several target species easier and faster. In order to test and make this tool operational,six species of commercial interest were selected: four species of fish hand two species of bivalves. It is proposed to estimate the proportion of illegal specimens in the studied lot from the proportion of illegal individuals found in the samples taken from this lot.The input data for the application are the minimum legal size(MLS) of the species and the total length(TL)of each specimen sampled. The out put data is a statistical summary of the percentage of specimens of size less than the legal minimum(TL<=MLS)within different confidence intervals(90%,95% and 99%). The software developed will serve as a fast,efficient and easy to manage tool that allows inspectors to determine the degree of compliance on MLS control and to make a decision supported by statistical proof on fishing goods

Every Fish Counts: Challenging Length–Weight Relationship Bias in Discards

Bycatch is a significant issue in global fisheries and understanding the length–weight relationships (LWR) of fish species can provide valuable insights for stock assessment and management efforts. In this study, we estimated the LWR of 74 fish species in trawl fleet discards from the Gulf of Cadiz, including 24 species for which LWR data had not been previously reported in this region. LWR was calculated from the formula W = aLb where parameter a is the intercept of the equation, related to body shape, and parameter b is the slope, which indicates the type of growth of the species. A total of 20,007 individuals from 40 families were measured and weighed. The most abundant species were Engraulis encrasicolus, Trachurus trachurus, Serranus hepatus, Sardina pilchardus, Capros aper, and Diplodus bellottii, and the Sparidae family was the most represented with ten species. The parameter b, which represents the type of growth, ranged from 2.1607 to 3.7040. A positive allometric growth trend was observed in 64% of the species. The inclusion of individuals with a low sample size proved useful, particularly for first reports in a new study area. However, caution should be taken when using these data, as the estimates of the length–weight relationship for these species may be less precise. Further studies with larger sample sizes are needed to confirm the results and improve the accuracy of the estimates. Overall, our findings contribute to the understanding of the LWR of fish species in the Gulf of Cadiz, informing future research and management efforts in the region.This research has been carried out within the framework of the ECOFISH project: ecoinnovative strategies for sustainable fishing in the Gulf of Cadiz SPA. This initiative has been supported by the Biodiversity Foundation, the Ministry for Ecological Transition and Demographic Challenge, through the Pleamar Program, co-financed by the European Maritime and Fisheries Fund (EMFF) [grant number: 2019-016/PV/PLEAMAR18/PT; 2020-013/PV/PLEAMAR19/PT; 2020- 055/PV/PLEAMAR20/PT; 2021/PV/PLEAMAR20-21/PT; 2021-060/PV/PLEAMAR21/PT]

Correlation between seabirds and fisheries varies by species at fine-scale pattern

Understanding how fisheries influence seabird distribution is critical in the development of sustainable fisheries management. Species distribution models were applied to analyse the influence of the fishing footprint, discards, and oceanographic factors on seabird attendance patterns to trawlers in the Gulf of Cadiz. More than 30 species of seabirds were attracted to trawlers, although only seven were registered with relatively high frequency and abundance. For these species, fishery footprint was a good predictor for the distribution of four out of seven (yellow-legged gull, lesser black-backed gull, northern gannet, and Cory's shearwater). Yellow-legged and lesser black-backed gull flocked in large numbers to trawlers, mostly in shallow areas where they were also attracted by purse seines. Northern gannets and Cory's shearwaters appeared with relatively high frequency and their distributions correlated with trawler effort and abundance of potential prey discards. Balearic shearwaters were attracted in low numbers and concentrated in shallow areas, where potential prey discards were also more abundant. For these three species, discards as surrogate of natural prey distribution were good predictors of trawler attendance. Our research revealed that, at a local scale, the degree of interaction of seabirds on fishing discards varies by species. Therefore, fine-scale studies are essential in identifying interactions between seabirds and fisheries, and thus assessing conservation issues such as bycatch or the consequences of discard bans.This research has been carried out within the framework of the ECOFISH project: Eco-innovative strategies for sustainable fishing in the Gulf of Cadiz SPA. This initiative has been supported by the Biodiversity Foundation, the Ministry for Ecological Transition and Demographic Challenge, through the Pleamar Program, co-financed by the European Maritime and Fisheries Fund (EMFF) [grant number: 2019016/PV/PLEAMAR18/PT; 2020-013/PV/PLEAMAR19/PT; 2020-055/PV/PLEAMAR20/PT; 2021/PV/PLEAMAR2021/PT]

Análisis de la investigación cualitativa en educación desarrollada en el estado español

En este artículo presentamos los resultados de una revisión sobre la investigación cualitativa en educación desarrollada en el Estado español, desde sus inicios hasta la actualidad. Los objetivos fueron analizar cómo y cuándo se inicia este tipo de investigación, cuáles eran las características del contexto sociopolítico en el que se produce, así como sus repercusiones, y cómo ha sido su desarrollo. Por ello, en primer lugar hacemos un breve análisis histórico y social, para interpretar posteriormente la producción de conocimiento generado en torno a esta modalidad metodológica. Finalmente, se hace un análisis de las estrategias de recogida y análisis de información utilizadas en la investigación cualitativa, tanto en las de corte interpretativo como en las orientadas a la comprensión y al cambio.In this article we presented the results of a review on the qualitative research in education developed in Spanish, from its beginnings to the present time. The objectives were to analyze how and when east type of research begins, which were the characteristics of the sociopolitical context in which it takes place, as well as its repercussions, and how it has been his development. For that reason, in the first place we do a brief one historical and social analysis, to later interpret the production of knowledge generated around this methodologic modality. Finally, an analysis becomes of the strategies of collection and used analyses of information in the qualitative investigation, as much in those of interpretative cut like in the oriented ones to the understanding and the change

Artisanal trawl fisheries as a sentinel of marine litter pollution

Systematic seafloor surveys are a highly desirable method of marine litter monitoring, but the high costs involved in seafloor sampling are not a trivial handicap. In the present work, we explore the opportunity provided by the artisanal trawling fisheries to obtain systematic data on marine litter in the Gulf of Cadiz between 2019 and 2021. We find that plastic was the most frequent material, with a prevalence of single-use and fishing-related items. Litter densities decreased with increasing distance to shore with a seasonal migration of the main litter hotspots. During pre-lockdown and post-lockdown stages derived from COVID-19, marine litter density decreased by 65 %, likely related to the decline in tourism and outdoor recreational activities. A continuous collaboration of 33 % of the local fleet would imply a removal of hundreds of thousands of items each year. The artisanal trawl fishing sector can play a unique role of monitoring marine litter on the seabe

Social network analysis as a tool to inform sustainable multi-sectoral management in complex marine socioecosystems

In complex marine socioecosystems, where multiple sectoral activities coexist, management can be especially complicated. This is the case of the coupled Guadalquivir estuary - Gulf of Cadiz (Ge-GoC) system. The Guadalquivir estuary (SW Spain) plays a central role in the whole Gulf of Cadiz since many fish species use these waters as a nursery area. Therefore, not only fisheries management is important but also the environmental status of the estuarine waters. The latter will have an effect on the adult populations via recruitment. Human activities that directly or indirectly influence the estuary include fishing, agriculture, shipping, saltworks, tourism or aquaculture among others. Conflict among them are common. In this context, we have used social network analyses as a first step to create an analysis and decision-support framework to achieve balanced socio-ecological ecosystem based management (EBM) to the Ge-GOC

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries