A preliminary genetic analysis of a recently rediscovered population of the Twaite shad (Alosa fallax) in the Ebro river, Spain (Western Mediterranean)

Abstract. The Ebro River delta is a relevant marine protected area in the western Mediterranean. In order to promote the conservation of its ecosystem and support operational decision making in this sensitive area, a three-site standard-range (13.5 MHz) CODAR SeaSonde high-frequency (HF) radar was deployed in December 2013. The main goal of this work is to explore basic features of the sea surface circulation in the Ebro deltaic region as derived from reliable HF radar surface current measurements. For this aim, a combined quality control methodology was applied: firstly, 1-year long (2014) real-time web monitoring of nonvelocity-based diagnostic parameters was conducted to infer both radar site status and HF radar system performance. The signal-to-noise ratio at the monopole exhibited a consistent monthly evolution, although some abrupt decreases (below 10 dB), occasionally detected in June for one of the radar sites, impacted negatively on the spatiotemporal coverage of total current vectors. It seemed to be sporadic episodes since radar site overall performance was found to be robust during 2014. Secondly, a validation of HF radar data with independent in situ observations from a moored current meter was attempted for May–October 2014. The accuracy assessment of radial and total vectors revealed a consistently high agreement. The directional accuracy of the HF radar was rated at better than 8°. The correlation coefficient and root mean square error (RMSE) values emerged in the ranges [0.58–0.83] and [4.02–18.31] cm s−1, respectively. The analysis of the monthly averaged current maps for 2014 showed that the HF radar properly represented basic oceanographic features previously reported, namely, the predominant southwestward flow, the coastal clockwise eddy confined south of the Ebro delta mouth, or the Ebro River impulsive-type freshwater discharge. The EOF analysis related the flow response to local wind forcing and confirmed that the surface current field evolved in space and time according to three significantly dominant modes of variability.

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A Copepod of the Genus Rhodinicola Levinsen, 1878 (Poecilostomatoida, Clausiidae) Parasitic On Clymenura Clypeata (Saint-Joseph, 1894) (Polychaeta, Maldanidae) From the Alfaques Inlet (Ebro River Delta, Spain, Western Mediterranean)

Crustaceana ◽

10.1163/156854093x00180 ◽

1993 ◽

Vol 64 (2) ◽

pp. 129-136 ◽

Cited By ~ 1

Author(s):

Romana Capaccioni ◽

Enrique Carbonell ◽

David Gras

Keyword(s):

Western Mediterranean ◽

River Delta ◽

Ebro River ◽

Specific Identification ◽

First Report ◽

Ebro River Delta

AbstractThis is the first report on copepodites parasitizing the maldanid polychaete Clymenura clypeata (De Saint-Joseph, 1894). Analysis of four specimens has permitted their assignation to the genus Rhodinicola Levinsen, 1878. However, specific identification of these parasites is hindered by incomplete development of the swimming legs. A discussion is provided of differences and similarities between our specimens and other species in the genus Rhodinicola.

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Occurrence and distribution of twaite shad (Alosa fallax Lacépède) in the lower Elbe River, Germany

Conservation of Endangered Freshwater Fish in Europe ◽

10.1007/978-3-0348-9014-4_16 ◽

1996 ◽

pp. 157-170 ◽

Cited By ~ 4

Author(s):

R. Thiel ◽

A. Sepülveda ◽

S. Oesmann

Keyword(s):

Elbe River ◽

Twaite Shad ◽

Alosa Fallax

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Marine and continental distribution and dynamic of the early spawning migration of twaite shad (Alosa fallax (Lacépède, 1803)) and allis shad (Alosa alosa (Linnaeus, 1758)) in the north-west of the Iberian Peninsula

Marine and Freshwater Research ◽

10.1071/mf14243 ◽

2016 ◽

Vol 67 (8) ◽

pp. 1229 ◽

Cited By ~ 3

Author(s):

D. J. Nachón ◽

M. Mota ◽

C. Antunes ◽

M. J. Servia ◽

F. Cobo

Keyword(s):

Iberian Peninsula ◽

Habitats Directive ◽

The European Union ◽

North West ◽

The North ◽

Allis Shad ◽

Alosa Alosa ◽

Twaite Shad ◽

In The Wild ◽

Alosa Fallax

Knowledge regarding the marine phase of twaite shad (Alosa fallax (Lacépède, 1803)) and allis shad (Alosa alosa (Linnaeus, 1758)) remains limited. To understand the coastal and continental distribution and dynamic of migration of these species, in the present study we collected official data records of marine landings (kg), separated according to species, for all fish markets in Galicia (north-west of the Iberian Peninsula) and undertook freshwater field sampling campaigns. The findings indicate that both species of shad exhibit a coastal distribution near the rivers where they spawn, namely the Minho and Ulla rivers. Catches at sea declined from January, a phenomenon that can be understood as the onset of migration to the rivers. Bycatch reports are important because both A. fallax and A. alosa are listed in the Annex V of the European Union Habitats Directive, which lists animal species whose exploitation and taking in the wild may be subject to management measures. However, for a better management of these species it is necessary to understand the magnitude of displacements and connection of shad populations at sea.

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THE INFLUENCE OF WATER TEMPERATURE AND FLOW ON YEAR CLASS STRENGTH OF TWAITE SHAD (ALOSA FALLAX FALLAX) FROM THE RIVER SEVERN, ENGLAND.

Bulletin Français de la Pêche et de la Pisciculture ◽

10.1051/kmae:2001030 ◽

2001 ◽

pp. 953-972 ◽

Cited By ~ 13

Author(s):

M. W. APRAHAMIAN ◽

C. D. APRAHAMIAN

Keyword(s):

Water Temperature ◽

Twaite Shad ◽

Class Strength ◽

Influence Of Water ◽

Alosa Fallax

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SIMILARITIES IN THE SURNAMES OF ISLAND AND CONTINENTAL POPULATIONS OF THE NORTH-WESTERN MEDITERRANEAN AREA

Journal of Biosocial Science ◽

10.1017/s0021932007002465 ◽

2008 ◽

Vol 40 (3) ◽

pp. 359-377 ◽

Cited By ~ 1

Author(s):

E. LUCCHETTI ◽

M. TASSO ◽

P. PIZZETTI ◽

S. DE IASIO ◽

G. U. CARAVELLO

Keyword(s):

Genetic Analysis ◽

Mediterranean Area ◽

Western Mediterranean ◽

Recent History ◽

Local Populations ◽

The North ◽

The Matrix ◽

Mediterranean Regions ◽

Geographical Position ◽

North Western

SummaryThis paper compares the structures of the surnames of 75 municipal populations living in six north-western Mediterranean regions. Its purpose is to unravel the relations between the local populations in Corsica and Sardinia and the links between these populations and those living in the Italian and French continental territory. On the basis of the matrix of similarity of surnames, some topological representations have been drafted showing the above-mentioned relations between populations under the light of their geographical position, their recent history and studies of genetic analysis. Corsica has an eterogeneous surname structure and evident similarity of the north with Tuscany and some centres of continental France. When only the populations of Sardinia were taken into consideration, it emerged that they differ among each other in relation to their geographical position and their history; when, instead, they were considered in relation to other populations outside the island, it was possible to observe that they form a highly different cluster. This study also identified many differences in the analysed geographical areas of Sardinia. In the minor islands – Elba, Giglio, Capraia – the structure of the surnames has a Tuscan origin as well as some similarity with other geographically distant areas, as in the case of the island of Giglio, if compared with some communities of Liguria.

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