scholarly journals Rapid Spread of the Invasive Brown Alga Rugulopteryx okamurae in a National Park in Provence (France, Mediterranean Sea)

Water ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2306
Author(s):  
Sandrine Ruitton ◽  
Aurélie Blanfuné ◽  
Charles-François Boudouresque ◽  
Dorian Guillemain ◽  
Valérie Michotey ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Brown Alga ◽  
National Park ◽  
Large Population ◽  
Algal Species ◽  
Paracentrotus Lividus ◽  
Northwest Pacific ◽  
Strait Of Gibraltar ◽  
Invasive Status ◽  
First Occurrence

The temperate Northwest Pacific brown alga Rugulopteryx okamurae (Dictyotales, Phaeophyceae) was first discovered in 2002 in the Mediterranean Sea in the Thau coastal lagoon (Occitania, France) and then again in 2015 along the southern side of the Strait of Gibraltar, where it was assigned with invasive status. We report here on the first occurrence of the species in the Northwest Mediterranean Sea in Calanques National Park (Marseille, France) in 2018. By 2020, a large population had developed, extending over 9.5 km of coastline, including highly protected no-take zones. The seafood trade, with R. okamurae used as packing material for sea urchin Paracentrotus lividus shipments from Thau Lagoon, could be the vector of its introduction into the Marseille area. As observed in the Strait of Gibraltar, R. okamurae is spreading rapidly along the Marseille coasts, suggesting an invasive pathway. The subtidal reefs are densely carpeted with R. okamurae, which overgrows most native algal species. Fragments of the alga are continuously detached by wave actions and currents, sedimenting on the seabed and potentially clogging fishing nets, and thus, impacting artisanal fishing or washing up on the beaches, where they rot and raise concern among local populations.

On the occurrence of three red algal species new to the Mediterranean Sea in Al-Hoceima National Park (Morocco)

2015 ◽  
Vol 58 (6) ◽  
Author(s):  
Hanaa Moussa ◽  
Michael J. Wynne ◽  
Mustapha Hassoun ◽  
Ghizlane Salhi ◽  
Hanaa Zbakh ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Red Algae ◽  
National Park ◽  
Algal Species ◽  
Red Algal ◽  
The Mediterranean ◽  
Al Hoceima

AbstractThe occurrence in Morocco of three species of red algae new to the Mediterranean Sea is reported:

A Near-Uniform Basin-Wide Sea Level Fluctuation of the Mediterranean Sea

2007 ◽  
Vol 37 (2) ◽  
pp. 338-358 ◽  
Author(s):  
Ichiro Fukumori ◽  
Dimitris Menemenlis ◽  
Tong Lee
Keyword(s):  
Atlantic Ocean ◽  
Mediterranean Sea ◽  
Sea Level ◽  
Ocean Circulation ◽  
Large Scale ◽  
Circulation Model ◽  
Level Fluctuation ◽  
Strait Of Gibraltar ◽  
Sea Level Fluctuation ◽  
The Mediterranean

Abstract A new basin-wide oscillation of the Mediterranean Sea is identified and analyzed using sea level observations from the Ocean Topography Experiment (TOPEX)/Poseidon satellite altimeter and a numerical ocean circulation model. More than 50% of the large-scale, nontidal, and non-pressure-driven variance of sea level can be attributed to this oscillation, which is nearly uniform in phase and amplitude across the entire basin. The oscillation has periods ranging from 10 days to several years and has a magnitude as large as 10 cm. The model suggests that the fluctuations are driven by winds at the Strait of Gibraltar and its neighboring region, including the Alboran Sea and a part of the Atlantic Ocean immediately to the west of the strait. Winds in this region force a net mass flux through the Strait of Gibraltar to which the Mediterranean Sea adjusts almost uniformly across its entire basin with depth-independent pressure perturbations. The wind-driven response can be explained in part by wind setup; a near-stationary balance is established between the along-strait wind in this forcing region and the sea level difference between the Mediterranean Sea and the Atlantic Ocean. The amplitude of this basin-wide wind-driven sea level fluctuation is inversely proportional to the setup region’s depth but is insensitive to its width including that of Gibraltar Strait. The wind-driven fluctuation is coherent with atmospheric pressure over the basin and contributes to the apparent deviation of the Mediterranean Sea from an inverse barometer response.

Embryotoxicity and spermiotoxicity of nanosized ZnO for Mediterranean sea urchin Paracentrotus lividus

2013 ◽  
Vol 254-255 ◽  
pp. 1-9 ◽  
Author(s):  
Sonia Manzo ◽  
Maria Lucia Miglietta ◽  
Gabriella Rametta ◽  
Silvia Buono ◽  
Girolamo Di Francia
Keyword(s):  
Mediterranean Sea ◽  
Sea Urchin ◽  
Paracentrotus Lividus ◽  
Nanosized Zno

scholarly journals Factors contributing to a striking shift in human–wildlife dynamics in Hemis National Park, India: 22 years of reported snow leopard depredation

Oryx ◽  
2018 ◽  
Vol 53 (1) ◽  
pp. 58-62 ◽  
Author(s):  
Pushpinder S. Jamwal ◽  
Jigmet Takpa ◽  
Michael H. Parsons
Keyword(s):  
National Park ◽  
Large Population ◽  
Well Being ◽  
Snow Leopard ◽  
Before And After ◽  
The Government ◽  
Hunting Regulations ◽  
Government Records ◽  
Snow Leopards ◽  
Free Ranging

AbstractHemis National Park of the Trans-Himalayas is home to a large population of the snow leopard Panthera uncia and increasing numbers of agro-pastoralists. To persist in this harsh terrain, farmers have to either farm livestock or hunt free-ranging, native ungulates. The availability of more livestock and fewer natural prey created a dynamic whereby snow leopards depredated livestock, followed by retaliatory killing of snow leopards. In 1992, to assist farmers and wildlife, the government enacted a cost-compensation scheme. Following a decade with marginally fewer depredation events, in 2002, two additional strategies were implemented: predator-proof holding pens and the Himalayan Homestay Programme. We assessed 22 years (1992–2013) of depredation data, comparing the periods before and after the additional initiatives. Government records showed that during 1992–2013, 1,624 livestock were depredated from 339 sites, with c. USD 15,000 paid as compensation. There were significantly more kills annually before (a mean of 41) than after (3.5) the initiatives, and mass killings (≥ 5 animals killed per attack) were significantly reduced from 5.5 to 0.5 events per year. Goats and sheep (57%) and horses (13%) comprised the majority of losses. The marked reduction in depredation occurred whilst regulations against hunting were being enforced, probably resulting in an increase in the number of wild prey as alternative food. We conclude that together, cost-compensation, tighter hunting regulations, improved holding pens and the Homestay Programme helped support the well-being of the community while aiding conservation efforts.

scholarly journals The Mediterranean Sea Overturning Circulation

2019 ◽  
Vol 49 (7) ◽  
pp. 1699-1721 ◽  
Author(s):  
Nadia Pinardi ◽  
Paola Cessi ◽  
Federica Borile ◽  
Christopher L. P. Wolfe
Keyword(s):  
Mediterranean Sea ◽  
Water Column ◽  
Eastern Mediterranean ◽  
Deep Ocean ◽  
Western Mediterranean ◽  
The Other ◽  
Strait Of Gibraltar ◽  
Water Formation ◽  
Dense Water Formation ◽  
Meridional Overturning

AbstractThe time-mean zonal and meridional overturning circulations of the entire Mediterranean Sea are studied in both the Eulerian and residual frameworks. The overturning is characterized by cells in the vertical and either zonal or meridional planes with clockwise circulations in the upper water column and counterclockwise circulations in the deep and abyssal regions. The zonal overturning is composed of an upper clockwise cell in the top 600 m of the water column related to the classical Wüst cell and two additional deep clockwise cells, one corresponding to the outflow of the dense Aegean water during the Eastern Mediterranean Transient (EMT) and the other associated with dense water formation in the Rhodes Gyre. The variability of the zonal overturning before, during, and after the EMT is discussed. The meridional basinwide overturning is composed of clockwise, multicentered cells connected with the four northern deep ocean formation areas, located in the Eastern and Western Mediterranean basins. The connection between the Wüst cell and the meridional overturning is visualized through the horizontal velocities vertically integrated across two layers above 600 m. The component of the horizontal velocity associated with the overturning is isolated by computing the divergent components of the vertically integrated velocities forced by the inflow/outflow at the Strait of Gibraltar.

scholarly journals The Meandering Path of a Drifter around the Western Alboran Gyre

2004 ◽  
Vol 34 (3) ◽  
pp. 685-692 ◽  
Author(s):  
Jesús García Lafuente ◽  
Javier Delgado
Keyword(s):  
Mediterranean Sea ◽  
Surveillance System ◽  
Relative Vorticity ◽  
Western Mediterranean ◽  
Tidal Currents ◽  
Strait Of Gibraltar ◽  
Short Scale ◽  
Western Mediterranean Sea ◽  
Alboran Basin ◽  
Drifter Trajectory

Abstract An accidentally released drifter in the eastern section of the Strait of Gibraltar, whose successive positions were tracked by the Argos surveillance system, was advected more than 170 km around the western Alboran gyre in the Alboran Sea of the western Mediterranean Sea during four days. The drifter trajectory along the gyre's periphery was wavelike around a hypothetical smoothed streamline, with a period of 35 h and an amplitude of approximately 2 km. Temperature observations confirm the wavelike nature of the trajectory. Neither tidal currents within the Alboran basin nor wind-related forcing are able to explain the observed path. The interaction of the incoming Atlantic jet and the western Alboran gyre at the place where they meet together with the existence of relative vorticity pulses of the Atlantic jet associated with tidal currents in the strait is put forward as a likely mechanism that generates short-scale eddies in which the drifter could have been trapped. The subsequent advection of such an eddy around the gyre would depict the observed wavelike trajectory.

scholarly journals Anthropogenic and natural CO<sub>2</sub> exchange through the Strait of Gibraltar

2009 ◽  
Vol 6 (4) ◽  
pp. 647-662 ◽  
Author(s):  
I. E. Huertas ◽  
A. F. Ríos ◽  
J. García-Lafuente ◽  
A. Makaoui ◽  
S. Rodríguez-Gálvez ◽  
...  
Keyword(s):  
Time Series ◽  
Atlantic Ocean ◽  
Mediterranean Sea ◽  
Mediterranean Basin ◽  
Inorganic Carbon ◽  
Strait Of Gibraltar ◽  
Anthropogenic Carbon ◽  
The Mediterranean ◽  
The Mediterranean Basin ◽  
Mediterranean Water

Abstract. The exchange of both anthropogenic and natural inorganic carbon between the Atlantic Ocean and the Mediterranean Sea through Strait of Gibraltar was studied for a period of two years under the frame of the CARBOOCEAN project. A comprehensive sampling program was conducted, which was design to collect samples at eight fixed stations located in the Strait in successive cruises periodically distributed through the year in order to ensure a good spatial and temporal coverage. As a result of this monitoring, a time series namely GIFT (GIbraltar Fixed Time series) has been established, allowing the generation of an extensive data set of the carbon system parameters in the area. Data acquired during the development of nine campaigns were analyzed in this work. Total inorganic carbon concentration (CT) was calculated from alkalinity-pHT pairs and appropriate thermodynamic relationships, with the concentration of anthropogenic carbon (CANT) being also computed using two methods, the ΔC* and the TrOCA approach. Applying a two-layer model of water mass exchange through the Strait and using a value of −0.85 Sv for the average transport of the outflowing Mediterranean water recorded in situ during the considered period, a net export of inorganic carbon from the Mediterranean Sea to the Atlantic was obtained, which amounted to 25±0.6 Tg C yr−1. A net alkalinity output of 16±0.6 Tg C yr−1 was also observed to occur through the Strait. In contrast, the Atlantic water was found to contain a higher concentration of anthropogenic carbon than the Mediterranean water, resulting in a net flux of CANT towards the Mediterranean basin of 4.20±0.04 Tg C yr−1 by using the ΔC* method, which constituted the most adequate approach for this environment. A carbon balance in the Mediterranean was assessed and fluxes through the Strait are discussed in relation to the highly diverse estimates available in the literature for the area and the different approaches considered for CANT estimation. This work unequivocally confirms the relevant role of the Strait of Gibraltar as a controlling point for the biogeochemical exchanges occurring between the Mediterranean Sea and the Atlantic Ocean and emphasizes the influence of the Mediterranean basin in the carbon inventories of the North Atlantic.

The reproductive biology of swordfish (Xiphias gladius) in the Strait of Gibraltar

2018 ◽  
Vol 99 (3) ◽  
pp. 649-659 ◽  
Author(s):  
Noureddine Abid ◽  
Amin Laglaoui ◽  
Abdelhay Arakrak ◽  
Mohammed Bakkali
Keyword(s):  
Mediterranean Sea ◽  
North Atlantic ◽  
Fork Length ◽  
Strait Of Gibraltar ◽  
Mixing Rate ◽  
The North ◽  
Lower Jaw ◽  
The North Atlantic ◽  
The Mediterranean ◽  
First Maturity

During the period from April to September for the years 2014–2016, 998 swordfishes caught by the Moroccan artisanal longline fishery in the Strait of Gibraltar were sampled to study the reproduction of this species in this mixing area between the Mediterranean Sea and the North Atlantic. The results showed that the sex ratio is slightly in favour of males for sizes smaller than 130 cm LJFL (Lower jaw-fork length), whereas females are more numerous in sizes larger than 140 cm LJFL. Fifty per cent of females were estimated to be mature at 170 cm LJFL, while for males, the size at first maturity was estimated to be 95 cm LJFL. The swordfish spawn from June to September, probably in the Mediterranean Sea. The findings of this study suggest that the reproductive characteristics of swordfish caught in the Strait of Gibraltar are similar to those of the Mediterranean swordfish, and a high mixing rate between the Mediterranean and the North Atlantic stocks occurs in the study area.

Spatial patterns and seasonal fluctuations of intertidal macroalgal assemblages from Tarifa Island, southern Spain: relationship with associated Crustacea

2010 ◽  
Vol 91 (1) ◽  
pp. 107-116 ◽  
Author(s):  
José M. Guerra-García ◽  
M. Pilar Cabezas ◽  
Elena Baeza-Rojano ◽  
J. Carlos García-Gómez
Keyword(s):  
Protected Area ◽  
Algal Species ◽  
Late Summer ◽  
Weather Conditions ◽  
Ulva Rigida ◽  
Seasonal Fluctuations ◽  
Strait Of Gibraltar ◽  
Valonia Utricularis ◽  
Fucus Spiralis ◽  
Chaetomorpha Aerea

The dominant intertidal algal species from Tarifa Island, Strait of Gibraltar, together with the associated peracarid crustacean community, were studied over a two-year period (December 2005–December 2007). Gelidium corneum and Gymnogongrus patens were dominant at the lower levels, close to the subtidal. Valonia utricularis, Osmundea pinnatifida, a turf of Caulacanthus ustulatus and Gelidium spp., Corallina elongata and Jania rubens were distributed in intermediate levels, while Ulva rigida, Chaetomorpha aerea and Fucus spiralis were collected from upper levels. The main intertidal seaweeds of Tarifa Island showed a perennial behaviour, but maximum values of biomass were registered during late spring and beginning of summer for most of species while the highest seawater temperatures were measured in late summer and beginning of autumn. Corallina elongata and Jania rubens, the dominant species which shared a niche at platforms of intermediate levels, showed an opposite behaviour, probably to avoid competence: C. elongata showed higher biomass in April–June and lower values in August–October–December, while biomass of J. rubens was higher in December–February and lower in April–August. Associated crustaceans, including mainly amphipods (gammarids and caprellids) were also present throughout the whole year with similar seasonality to seaweeds. However, crustacean density in the intertidal was not only influenced by distribution of algae as substrate, but also by external factors, such as hydrodynamism, oxygen, weather conditions, competition or predation. The present study constitutes the first baseline study dealing with seasonal fluctuations of algae and associated crustaceans in a protected area of the Strait of Gibraltar, an important biogeographical zone between Europe and Africa and the Mediterranean and Atlantic.

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