Modelling the relationships of medium and long-term variations of the anchovy and sardine catches in the Catalan Sea (NW Mediterranean) with the environmental drivers

Versió amb una secció retallada, per drets de l'editorThe understanding of the driving forces involved in the abundance fluctuation of fish populations is an important requirement for conservation and management, especially in the context of environmental changes. In the North Western Mediterranean Sea the catches of sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) during the period 1990-2014 have severealy decreased. Although neither of the two populations is considered underexploited, it seems unlikely that overexploitation alone has caused the recent decrease. Furthermore, it is even truer considering that changes in the marine environment have occurred in the studied area during the last 40 years. The general objective of this PhD thesis is to detect the main environmental factors involved in the fluctuations of the abundance of the two small pelagic species in the Catalan Sea. Before focusing on the environmental influences, the spatiotemporal distribution of the purse seine fishery operations was analyzed. The results revealed that the distribution of the fleet captured the features of the distributions of small pelagic populations. These findings contributed to a better understanding and visualization of the spatial distribution of catches, which form the basis of the landings data series studied in the rest of the PhD thesis. We then investigated the local environmental factors and climate index (Western Mediterranean oscillation index; WeMOI) that were strictly linked with landings of both species. We concluded that temperature, salinity, and currents were important drivers for both species, and the WeMOI index favored sardine abundance when it was in positive phase. We highlighted that the relationships between the availability of these small pelagic fishes and these factors were better described by non-linearity. Finally, we provided evidence, independent from the studies directly targeted on early life stages, that the temperature and sea surface height (used as a proxy of mesoscale processes) play an important role in the recruitment variability of these species. Even more importantly we showed that the effects of these drivers were not stationary but transient over time. Although this work is one step forward in the understanding of the abundance variability of the small pelagic fish in the Catalan Sea further investigation focused especially on the synergic effects of fishing combined with environmental factors will still be needed.La comprensió dels factors implicats en la fluctuació d'abundància de les poblacions de peixos és un requisit important per a la conservació i la gestió, especialment en el context dels canvis ambientals. En la Mediterrània occidental, les captures de sardina (Sardina pilchardus) i l'anxova (Engraulis encrasicolus) durant el període 1990-2014 han disminuït bruscament. Malgrat que cap de les dues poblacions es consideri subexplotada, és poc probable que només la sobreexplotació hagi causat la recent disminució. Això és encara més cert si es té en compte que dins a la zona estudiada durant els últims 40 anys s'han produït clars canvis en el medi marí. L'objectiu general d'aquesta tesi doctoral és detectar els principals factors ambientals que intervenen en les fluctuacions de l'abundància de les dues espècies de petits pelàgics del mar català. Abans de centrar-se en les influències mediambientals, s'ha analitzat la distribució espaciotemporal de les operacions de la pesca de teranyina. Els resultats han revelat que la distribució de la flota representa fidelment les característiques de les distribucions de petits pelàgics. Aquestes troballes han contribuït a una millor comprensió i visualització de la distribució espacial de les captures que formen també la base de la sèrie de dades de desembarcament estudiada a la resta de la tesi doctoral. A continuació, s'han investigat les relacions entre els desembarcaments d'ambdues espècies i els factors ambientals locals i l'índex climàtic (Índex d'oscil·lació de la Mediterrània occidental, WeMOI). Es conclou que la temperatura, la salinitat i els corrents són factors importants per ambdues espècies, i l'índex WeMOI afavoreix l'abundància de la sardina quan es troba en fase positiva. Hem destacat que la relacions entre la disponibilitat d'aquestes espècies de petits pelàgics i aquests factors poden ser millor descrits amb models no-lineals. Finalment, aportem evidències, de manera independent d'altres estudis centrats directament en ous i larves, que la temperatura i el nivell superficial del mar (utilitzat com proxy de processos de mesoescala ) tenen un important rol en la variabilitat del reclutament per ambdues espècies. Encara més important, hem mostrat que els efectes d'aquests factors no són estacionaris sinó que han canviat amb el pas del temps. Encara que aquest estudi representa un pas endavant en el coneixement i la comprensió de la variabilitat en l'abundància de petits peixos pelàgics al mar Català, encara és necessària la investigació addicional centrada en l`efecte sinèrgic de la pesca amb els factors ambientals.Postprint (published version

Modelling the relationships of medium and long-term variations of the anchovy and sardine catches in the Catalan Sea (NW Mediterranean) with the environmental drivers

The understanding of the driving forces involved in the abundance fluctuation of fish populations is an important requirement for conservation and management, especially in the context of environmental changes. In the North Western Mediterranean Sea the catches of sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) during the period 1990-2014 have severealy decreased. Although neither of the two populations is considered underexploited, it seems unlikely that overexploitation alone has caused the recent decrease. Furthermore, it is even truer considering that changes in the marine environment have occurred in the studied area during the last 40 years. The general objective of this PhD thesis is to detect the main environmental factors involved in the fluctuations of the abundance of the two small pelagic species in the Catalan Sea. Before focusing on the environmental influences, the spatiotemporal distribution of the purse seine fishery operations was analyzed. The results revealed that the distribution of the fleet captured the features of the distributions of small pelagic populations. These findings contributed to a better understanding and visualization of the spatial distribution of catches, which form the basis of the landings data series studied in the rest of the PhD thesis. We then investigated the local environmental factors and climate index (Western Mediterranean oscillation index; WeMOI) that were strictly linked with landings of both species. We concluded that temperature, salinity, and currents were important drivers for both species, and the WeMOI index favored sardine abundance when it was in positive phase. We highlighted that the relationships between the availability of these small pelagic fishes and these factors were better described by non-linearity. Finally, we provided evidence, independent from the studies directly targeted on early life stages, that the temperature and sea surface height (used as a proxy of mesoscale processes) play an important role in the recruitment variability of these species. Even more importantly we showed that the effects of these drivers were not stationary but transient over time. Although this work is one step forward in the understanding of the abundance variability of the small pelagic fish in the Catalan Sea further investigation focused especially on the synergic effects of fishing combined with environmental factors will still be needed.La comprensió dels factors implicats en la fluctuació d'abundància de les poblacions de peixos és un requisit important per a la conservació i la gestió, especialment en el context dels canvis ambientals. En la Mediterrània occidental, les captures de sardina (Sardina pilchardus) i l'anxova (Engraulis encrasicolus) durant el període 1990-2014 han disminuït bruscament. Malgrat que cap de les dues poblacions es consideri subexplotada, és poc probable que només la sobreexplotació hagi causat la recent disminució. Això és encara més cert si es té en compte que dins a la zona estudiada durant els últims 40 anys s'han produït clars canvis en el medi marí. L'objectiu general d'aquesta tesi doctoral és detectar els principals factors ambientals que intervenen en les fluctuacions de l'abundància de les dues espècies de petits pelàgics del mar català. Abans de centrar-se en les influències mediambientals, s'ha analitzat la distribució espaciotemporal de les operacions de la pesca de teranyina. Els resultats han revelat que la distribució de la flota representa fidelment les característiques de les distribucions de petits pelàgics. Aquestes troballes han contribuït a una millor comprensió i visualització de la distribució espacial de les captures que formen també la base de la sèrie de dades de desembarcament estudiada a la resta de la tesi doctoral. A continuació, s'han investigat les relacions entre els desembarcaments d'ambdues espècies i els factors ambientals locals i l'índex climàtic (Índex d'oscil·lació de la Mediterrània occidental, WeMOI). Es conclou que la temperatura, la salinitat i els corrents són factors importants per ambdues espècies, i l'índex WeMOI afavoreix l'abundància de la sardina quan es troba en fase positiva. Hem destacat que la relacions entre la disponibilitat d'aquestes espècies de petits pelàgics i aquests factors poden ser millor descrits amb models no-lineals. Finalment, aportem evidències, de manera independent d'altres estudis centrats directament en ous i larves, que la temperatura i el nivell superficial del mar (utilitzat com proxy de processos de mesoescala ) tenen un important rol en la variabilitat del reclutament per ambdues espècies. Encara més important, hem mostrat que els efectes d'aquests factors no són estacionaris sinó que han canviat amb el pas del temps. Encara que aquest estudi representa un pas endavant en el coneixement i la comprensió de la variabilitat en l'abundància de petits peixos pelàgics al mar Català, encara és necessària la investigació addicional centrada en l`efecte sinèrgic de la pesca amb els factors ambientals

Ocurrencia de anchoa adulta en Cataluña (Mediterráneo noroccidental) en relación a las condiciones superficiales del mar

Generalized additive and generalized additive threshold models were used to study the relationship between landings per unit effort (LPUE) of anchovy, Engraulis encrasicolus, during the spawning season (May-October) from 2000-2010, and environmental variables, using sea surface data derived from satellite imagery (temperature, salinity, chlorophyll a, and meridional and zonal velocity current) in three fishing zones defined along the Catalan coast. The configuration of the environment where spawning aggregations occur affects early life stages and therefore the future demographic structure of the population. It is therefore fundamental to define the environmental conditions and their variations during the spawning season. Our results show that the low salinity in the Northern and Central sector and the velocity of the zonal and meridional currents in the Central and Southern sector, respectively, implicated in retention processes, increase LPUE during the spawning period. Temperature was related to LPUE in the Southern and in the Northern sectors, in both of which a non-linear positive effect with a local maximum peak at lower temperature values was present. However, in the Northern sector, this relationship held only for the period before 2007. After 2007 the decrease in preferred temperature suggests a reduction of the thermal window in which adult spawner aggregations occur. In agreement with previous studies on this species, the relationships were non-linear, stressing the importance of the match in timing and location between favourable conditions and spawning period as a crucial event for understanding the dynamics of small pelagics populations.Con el objeto de estudiar la relación entre descargas por unidad de esfuerzo (LPUE) de la anchoa, Engraulis encrasicolus, durante la época de puesta (Mayo-Octubre) y variables ambientales marinas obtenidas por observación de satélite (temperatura, salinidad, clorofila-a, velocidad de corriente zonal y meridional) se analizaron series de datos para el periodo 2000-2010 mediante modelos aditivos generalizados, con y sin umbral, en tres zonas de pesca de la costa catalana. La configuración del ambiente en que ocurren las agregaciones de puesta afecta a los estadios tempranos y, por consiguiente, a la estructura demográfica futura de las poblaciones. Por lo tanto es de gran importancia definir las condiciones ambientales y sus variaciones durante la época de puesta. Los resultados del análisis muestran que bajas salinidades en los sectores norte y central, y las velocidades zonal y meridional de la corriente, en los sectores central y sur respectivamente, implicadas en los procesos de retención hacen aumentar la LPUE durante el periodo de puesta. La temperatura se relacionó con la LPUE en los sectores sur y norte. En ambas zonas se observó un efecto positivo y no lineal con un pico máximo a valores de temperatura bajos. Sin embargo, en el sector norte esta relación se mantuvo solamente hasta 2007. Después de 2007, la disminución en la temperatura preferencial sugiere una reducción en la ventana térmica en la que ocurren las agregaciones de puesta. Las relaciones obtenidas son no lineales, coincidiendo con estudios previos en esta especie, haciendo resaltar la importancia del ajuste espacio-temporal entre condiciones favorables y periodo de puesta como evento crucial para entender la dinámica poblacional de los pequeños pelágicos

Length-Weight Relationships of 52 Species from the South of Sicily (Central Mediterranean Sea)

The Length-Weight relationships (LWRs) of 52 species (14 never reported before) of fishes, crustaceans and cephalopods living on the shelf and upper slope off Southern Sicily are provided. Data were collected in the framework of the International bottom trawl survey in the Mediterranean (MEDITS) in the South of Sicily (Central Mediterranean), covering a time frame ranging from 2012 to 2019. Linear regressions were significant for all species (p < 0.05) with R-2 values ranging from 0.86 to 0.99. The intercept (a) of LWRs ranged from 0.0003 to 0.4677, while the slope (b) ranged from 2.1281 to 3.306. The Welch t-test, used to evaluate differences between the obtained LWRs with those reported in the literature, revealed that most of the LWRs (about 55%) reported in this study are in disagreement with those obtained previously by other authors from the Strait of Sicily. It is expected that the results obtained from this study will contribute to filling the knowledge gap of fish populations in this area and also assist fisheries scientists in future stock assessment studies

Plastic adjustments of biparental care behavior across embryonic development under elevated temperature in a marine ectotherm

Phenotypic plasticity in parental care investment allows organisms to promptly respond to rapid environmental changes by potentially benefiting offspring survival and thus parental fitness. To date, a knowledge gap exists on whether plasticity in parental care behaviors can mediate responses to climate change in marine ectotherms. Here, we assessed the plasticity of parental care investment under elevated temperatures in a gonochoric marine annelid with biparental care, Ophryotrocha labronica, and investigated its role in maintaining the reproductive success of this species in a warming ocean. We measured the time individuals spent carrying out parental care activities across three phases of embryonic development, as well as the hatching success of the offspring as a proxy for reproductive success, at control (24℃) and elevated (27℃) temperature conditions. Under elevated temperature, we observed: (a) a significant decrease in total parental care activity, underpinned by a decreased in male and simultaneous parental care activity, in the late stage of embryonic development; and (b) a reduction in hatching success that was however not significantly related to changes in parental care activity levels. These findings, along with the observed unaltered somatic growth of parents and decreased brood size, suggest that potential cost-benefit trade-offs between offspring survival (i.e., immediate fitness) and parents' somatic condition (i.e., longer-term fitness potential) may occur under ongoing ocean warming. Finally, our results suggest that plasticity in parental care behavior is a mechanism able to partially mitigate the negative effects of temperature-dependent impacts. -- Keywords : Behavioral plasticity ; Brood size ; Global warming ; Hatching success ; Invertebrates ; Parental investment

Unilateral Blepharoptosis from Renal Cell Carcinoma

Blepharoptosis is the drooping or inferior displacement of the upper eyelid. Blepharoptosis can be either congenital or acquired. Tumour metastasis is one of the acquired causes of blepharop-tosis. The lungs, locoregional lymph nodes, bone and liver are the usual sites of metastases of renal cell carcinoma (RCC); however, unusual locations of RCC have also been reported. Herein, we describe a case of a 47-year-old man with unilateral ptosis and blurred vision due to meta-static RCC. We describe the different causes of blepharopstosis, the path that led to the diagno-sis, and how RCC can metastasize to unusual anatomical regions such as the orbit. Symptoms such as exophthalmos, lid edema, diplopia, ptosis, cranial nerve paralysis or blurred vision may mime a benign disease; however, they could also be the symptoms of a systemic malignancy

Imaging of Renal Medullary Carcinoma

Renal medullary carcinoma (RMC) is a rare, highly aggressive tumor recognized as an independent pathological entity. African-descent adolescents and young adults with sickle cell hemoglobinopathy are the most affected groups. This rare subtype of renal cell carcinoma has its own morphogenetic and pathological characteristics. The major clinical manifestations include gross hematuria, abdominal or flank pain, and weight loss. The prognosis is very poor, with 95% of cases diagnosed at an advanced stage of the disease. In this review, we summarize the morphologic and dynamic characteristics of RMC under various imaging modalities such as ultrasound, computed tomography, and magnetic resonance. Differential diagnosis and management strategies are also discussed

SeaConditions: a web and mobile service for safer professional and recreational activities in the Mediterranean Sea

Abstract. Reliable and timely information on the environmental conditions at sea is key to the safety of professional and recreational users as well as to the optimal execution of their activities. The possibility of users obtaining environmental information in due time and with adequate accuracy in the marine and coastal environment is defined as sea situational awareness (SSA). Without adequate information on the environmental meteorological and oceanographic conditions, users have a limited capacity to respond, which has led to loss of lives and to large environmental disasters with enormous consequent damage to the economy, society and ecosystems. Within the framework of the TESSA project, new SSA services for the Mediterranean Sea have been developed. In this paper we present SeaConditions, which is a web and mobile application for the provision of meteorological and oceanographic observation and forecasting products. Model forecasts and satellite products from operational services, such as ECMWF and CMEMS, can be visualized in SeaConditions. In addition, layers of information related to bathymetry, sea level and ocean-colour data (chl a and water transparency) are displayed. Ocean forecasts at high spatial resolutions are included in the version of SeaConditions presented here. SeaConditions provides a user-friendly experience with a fluid zoom capability, facilitating the appropriate display of data with different levels of detail. SeaConditions is a single point of access to interactive maps from different geophysical fields, providing high-quality information based on advanced oceanographic models. The SeaConditions services are available through both web and mobile applications. The web application is available at www.sea-conditions.com and is accessible and compatible with present-day browsers. Interoperability with GIS software is implemented. User feedback has been collected and taken into account in order to improve the service. The SeaConditions iOS and Android apps have been downloaded by more than 105 000 users to date (May 2016), and more than 100 000 users have visited the web version