Zooplankton Abundance and Diversity in the Tropical and Subtropical Ocean

The abundance and composition of zooplankton down to 3000 m depth was studied in the subtropical and tropical latitudes across the Atlantic, Pacific and Indian Oceans (35 N–40 S). Samples were collected from December 2010 to June 2011 during the Malaspina Circumnavigation Expedition. Usually, low abundances were observed with the highest values found in the North Pacific Ocean, Benguela, and o Mauritania, and the lowest in the South Pacific Ocean. No significant di erences in abundance and zooplankton composition were found among oceans, with depth being consistently the most important factor a ecting their distribution. Each depth strata were inhabited by distinct copepod assemblages, which significantly di ered among the strata. The contribution of copepods to the zooplankton community increased with the depth although, as expected, their abundance strongly decreased. Among the copepods, 265 species were identified but 85% were rare and contributed less than 1% in abundance. Clausocalanus furcatus and Nannocalanus minor dominated the epipelagic strata. Pleuromamma abdominalis and Lucicutia clausi were of importance in the mesopelagic layer, and Pareucalanus, Triconia, Conaea and Metridia brevicauda in the bathypelagic layer. Our results provide a global-scale assessment of copepod biodiversity and distribution, providing a contemporary benchmark to follow future ocean changes at low latitudes

Update of electronic tagging data and methodologies for Atlantic bluefin tuna in order to plan future tagging activities

This document presents the current electronic tagging information available for management strategy evaluation. This information also allows to identify gaps, in sizes and geographical areas, that should be taken into account to plan future tagging activities. It also describes the status of current electronic tag databases, advantages and disadvantages of electronic tags used on Atlantic bluefin tuna and outlines the technological advances that will allow the use of different types of tags (pop-up satellite archival, archival internal and acoustic tags) to improve the description of movements of this species. The conclusions section summarizes the progress needed to develop the use of electronic tagging on Atlantic bluefin tuna

Abundance and Structure of the Zooplankton Community During a Post-eruptive Process: The Case of the Submarine Volcano Tagoro (El Hierro; Canary Islands), 2013-2018

The mesozooplankton community was analyzed over a 6-year period (2013-2018) during the post-eruptive stage of the submarine volcano Tagoro, located south of the island of El Hierro (Canary Archipelago, Spain). Nine cruises from March 2013 to March 2018 were carried out in two different seasons, spring (March-April) and autumn (October). A high-resolution study was carried out across the main cones of Tagoro volcano, as well as a large number of reference stations surrounding El Hierro (unaffected by the volcano). The zooplankton community at the reference stations showed a high similarity with more than 85% of the variation in abundance and composition attributable to seasonal differences. Moreover, our data showed an increase in zooplankton abundance in waters affected by the volcano with a higher presence of non-calanoid copepods and a decline in the diversity of the copepod community, indicating that volcanic inputs have a significant effect on these organisms. Fourteen different zooplankton groups were found but copepods were dominant (79%) with 59 genera and 170 species identified. Despite the high species number, less than 30 presented a larger abundance than 1%. Oncaea and Clausocalanus were the most abundant genera followed by Oithona and Paracalanus (60%). Nine species dominated (>2%): O. media, O. plumifera, and O. setigera among the non-calanoids and M. clausi, P. nanus, P. parvus, C. furcatus, C. arcuicornis, and N. minor among the calanoids. After the initial low abundance of the copepods as a consequence of the eruption, an increase was observed in the last years of the study, where besides the small Paracalanus and Clausocalanus, the Cyclopoids seem to have a good adaptive strategy to the new water conditions. The increase in zooplankton abundance and the decline in the copepod diversity in the area affected by the volcano indicate that important changes in the composition of the zooplankton community have occurred. The effect of the volcanic emissions on the different copepods was more evident in spring when the water was cooler and the mixing layer was deeper. Further and longer research is recommended to monitor the zooplankton community in the natural laboratory of the Tagoro submarine volcano.En prens

Identification and characterization of esential habitats for three cephalopod species in the national parks of Galician Atlantic Islands and Cabrera

31 pages, 16 figures, 8 tables, 1 appendix[EN] We evaluated specific habitat features (bottom substrate type, depth, temperature and season) at random locations in the Cíes archipelago (Galician Atlantic Islands National Park, NW Spain) and to determine their impact on Octopus vulgaris, Sepia officinalis and Loligo vulgaris habitat use. We performed 113 underwater visual transects by scuba diving between April 2012 and August 2015. Habitat features were evaluated as predictors of the presence/absence of spawning dens and egg clusters using Generalized Additive Models. The O. vulgaris spawning essential habitats was found between 5 and 30 m depth in rocky bottoms from Punta Escodelo to Punta Ferreiro (Monteagudo Island), which surface is 6% of the total marine area of the Cíes islands. We propose a complete protection of this area for exploitation. underwater visual transects also showed that there is an O. vulgaris hatchery essential habitat (specimens ≤1000 g) in the sandy bottoms of the Rodas inlet. This small area (2.8% of the total) could be also protected. S. officinalis results revealed two SEH: Bajo de Viños and Piedra del Borrón, hard bottom shoals between 8-13 m covered by sea fans and sea worms and located in the central Cíes islands. We also suggest protecting that small area (0.28% of the total). Very few L. vulgaris eggs masses were found with underwater visual transects and artificial devices attractors in the Cíes islands. Also very few specimens of O. vulgaris and S. officinalis were found with underwater visual transects in Cabrera National Park between 5 and 50 m depth. Two squid spawning essential habitats were located in that park using artificial devices attractors: Na Redona and Ses Rates, both on sandy bottoms from 18 to 50 m depth with fast marine currents. The spawning essential habitats found reveal indicators of three species habitat selection and should help to identify targets for habitat improvement projects and ecosystem management approaches[ES] Mediante 112 censos visuales con escafandra autónoma realizados entre abril de 2012 y agosto de 2015, distribuidos aleatoriamente en el archipiélago de Cíes (Parque Nacional de las Islas Atlánticas de Galicia), se evaluaron las características (tipo de sustrato, profundidad, temperatura y estación) de los hábitats esenciales de Octopus vulgaris, Sepia officinalis y Loligo vulgaris. Dichas características se emplearon como predictores de la presencia/ausencia de guaridas de desove o masas de huevos utilizando Modelos Aditivos Generalizados. El hábitat esencial para el desove de O. vulgaris se localizó entre 5 y 30 m de profundidad en fondos rocosos entre Punta Escodelo y Punta Ferreiro (isla de Monteagudo), cuya superficie es del 6% del total. Proponemos su protección completa para la explotación. Los censos visuales con escafandra autónoma mostraron un hábitat esencial de cría de O. vulgaris en fondos arenosos de la ensenada de Rodas. Esta pequeña área (2,8% del total) podría ser también protegida. Los resultados para S. officinalis revelaron dos HE para el desove: el Bajo de Viños y la Piedra del Borrón, bancos de fondo duro entre 8-13 m cubiertos por gorgonias y poliquetos tubícolas en la ensenada de Rodas. Se sugiere protección para este área (0,28% del total). Apenas se hallaron puestas de L. vulgaris con censos visuales con escafandra autónoma y Dispositivos Atractores de Puesta en Cíes. También se observaron muy escasos ejemplares de S. officinalis y O. vulgaris con censos visuales con escafandra autónoma entre 5 y 50 m de profundidad en el Parque Nacional de Cabrera. Se identificaron dos HE para el desove del calamar en el Parque Nacional de Cabrera usando Dispositivos Atractores de Puesta: Na Redona y Ses Rates, fondos arenosos entre 18 y 50 m de profundidad con rápidas corrientes. Estos HEs son indicadores de selección del hábitat, y constituyen un notable apoyo para identificar objetivos en proyectos de conservación de hábitats y enfoques ecosistémicos en la gestión pesqueraMiguel Cabanellas-Reboredo fue becado por la Conselleria de Educació del Govern de les Illes Balears (Fondo Social Europeo) y actualmente beneficiario de contrato post-doctoral Juan de la Cierva formación (MINECO). Marta Sestelo disfrutó de beca de investigación SFRH/BPD/93928 de Fundacão Ciência e Tecnologia de Portugal y de proyectos del Ministerio de Ciencia e Innovación y la Xunta de Galicia. Este proyecto estuvo financiado por el Organismo Autónomo de Parques Nacionales del Ministerio de Agricultura, Alimentación y Medio Ambiente (CEFAPARQUES, Proyecto número: 458/2011)N

Tracking a mass mortality outbreak of pen shell Pinna nobilis populations: A collaborative effort of scientists and citizens

A mass mortality event is devastating the populations of the endemic bivalve Pinna nobilis in the Mediterranean Sea from early autumn 2016. A newly described Haplosporidian endoparasite (Haplosporidium pinnae) is the most probable cause of this ecological catastrophe placing one of the largest bivalves of the world on the brink of extinction. As a pivotal step towards Pinna nobilis conservation, this contribution combines scientists and citizens' data to address the fast- and vast-dispersion and prevalence outbreaks of the pathogen. Therefore, the potential role of currents on parasite expansion was addressed by means of drift simulations of virtual particles in a high-resolution regional currents model. A generalized additive model was implemented to test if environmental factors could modulate the infection of Pinna nobilis populations. The results strongly suggest that the parasite has probably dispersed regionally by surface currents, and that the disease expression seems to be closely related to temperatures above 13.5 degrees C and to a salinity range between 36.5-39.7 psu. The most likely spread of the disease along the Mediterranean basin associated with scattered survival spots and very few survivors (potentially resistant individuals), point to a challenging scenario for conservation of the emblematic Pinna nobilis, which will require fast and strategic management measures and should make use of the essential role citizen science projects can play

Terms of reference for the mediterranean tuna habitat observatory initiative

[EN] We present the Terms of Reference for a case study on a Mediterranean eco-region focusing on the environmental component of the Ecosystem Report Card. The objective of this case study is to describe and monitor the variability of environmental processes in the Mediterranean Sea that affect the ecology of large pelagic fishes, with a particular attention on tunas, and the possible role of climate change on this variability. Here we define the objectives and activities of the initiative, the participant roles, primary indicators and the methodological approach[FR] Ce document présente les termes de référence d’une étude de cas sur une écorégion méditerranéenne consacrée à la composante environnementale de la fiche informative sur les écosystèmes. L'objectif de cette étude de cas est de décrire et de suivre la variabilité des processus environnementaux en mer Méditerranée qui affectent l'écologie des grands poissons pélagiques, en accordant une attention particulière aux thonidés, et de déterminer le rôle possible du changement climatique sur cette variabilité. Nous définissons ici les objectifs et les activités de l'initiative, les rôles des participants, les indicateurs primaires et l'approche méthodologique.[ES] En el documento se presentan los términos de referencia para un estudio de caso sobre una ecorregión mediterránea centrado en el componente medioambiental de la ficha informativa sobre ecosistemas. El objetivo de este estudio de caso es describir y hacer un seguimiento de la variabilidad de los procesos medioambientales en el mar Mediterráneo que afectan a la ecología de los grandes peces pelágicos, con especial atención a los túnidos, y el posible papel del cambio climático en esta variabilidad. A continuación, se definen los objetivos y actividades de la iniciativa, las funciones de los participantes, los indicadores principales y el enfoque metodológico.Peer reviewe

Human Stressors Are Driving Coastal Benthic Long-Lived Sessile Fan Mussel Pinna nobilis Population Structure More than Environmental Stressors.

Coastal degradation and habitat disruption are severely compromising sessile marine species. The fan shell Pinna nobilis is an endemic, vulnerable species and the largest bivalve in the Mediterranean basin. In spite of species legal protection, fan shell populations are declining. Models analyzed the contributions of environmental (mean depth, wave height, maximum wave height, period of waves with high energy and mean direction of wave source) versus human-derived stressors (anchoring, protection status, sewage effluents, fishing activity and diving) as explanatory variables depicting Pinna nobilis populations at a mesoscale level. Human stressors were explaining most of the variability in density spatial distribution of fan shell, significantly disturbing benthic communities. Habitat protection affected P. nobilis structure and physical aggression by anchoring reveals a high impact on densities. Environmental variables instead played a secondary role, indicating that global change processes are not so relevant in coastal benthic communities as human-derived impacts.Versión del editor4,411

Genetic and oceanographic tools reveal high population connectivity and diversity in the endangered pen shell Pinna nobilis

For marine meta-populations with source-sink dynamics knowledge about genetic connectivity is important to conserve biodiversity and design marine protected areas (MPAs). We evaluate connectivity of a Mediterranean sessile species, Pinna nobilis. To address a large geographical scale, partial sequences of cytochrome oxidase I (COI, 590 bp) were used to evaluate phylogeographical patterns in the Western Mediterranean, and in the whole basin using overlapping sequences from the literature (243 bp). Additionally, we combined (1) larval trajectories based on oceanographic currents and early life-history traits and (2) 10 highly polymorphic microsatellite loci collected in the Western Mediterranean. COI results provided evidence for high diversity and low inter-population differentiation. Microsatellite genotypes showed increasing genetic differentiation with oceanographic transport time (isolation by oceanographic distance (IBD) set by marine currents). Genetic differentiation was detected between Banyuls and Murcia and between Murcia and Mallorca. However, no genetic break was detected between the Balearic populations and the mainland. Migration rates together with numerical Lagrangian simulations showed that (i) the Ebro Delta is a larval source for the Balearic populations (ii) Alicante is a sink population, accumulating allelic diversity from nearby populations. The inferred connectivity can be applied in the development of MPA networks in the Western Mediterranean.Spanish Ministry of Economy and Competitiveness [CTM2009-07013]; Ramon y Cajal Fellowship [RYC2014-14970]; Conselleria d'Innovacio, Recerca i Turisme of the Balearic Government; Spanish Ministry of Economy, Industry and Competitiveness IFCT [IF/00998/2014]; FCT [SFRH/BPD/63703/2009, SFRH/BPD/107878/2015, EXCL/AAG-GLO/0661/2012]; National Science Foundation [OCE-1419450]; Albert II of Monaco Foundationinfo:eu-repo/semantics/publishedVersio