Sightings of risso’s dolphin (grampus griseus) off the Southern coast of Linosa island (South-Central Mediterranean Sea)

Risso’s dolphin distribution, habitat preferences, and site fidelity in the Strait of Sicily are very little known. During three summer seasons of sea surveys, we sighted this species offshore Linosa island in groups of variable numbers of individuals (2-20 with an average of 9.7 ± 7.0 SD). Sightings were located in a small area showing medium depth (average 591 m) and bathymetric features that usually correspond with known habitat preferences of the species. A total of 32 individuals belonging to 4 age classes were photo-identified and 8 of them were re-sighted once over years. This work illustrates for the first time, the presence of the species in the studied area and the results seem to indicate a site fidelity over years.

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Social structure of Risso’s dolphins (Grampus griseus) at the Azores: a stratified community based on highly associated social units

Canadian Journal of Zoology ◽

10.1139/z07-138 ◽

2008 ◽

Vol 86 (4) ◽

pp. 294-306 ◽

Cited By ~ 47

Author(s):

K. L. Hartman ◽

F. Visser ◽

A. J.E. Hendriks

Keyword(s):

Social Structure ◽

Site Fidelity ◽

Adult Males ◽

Community Based ◽

Grampus Griseus ◽

The Social ◽

Risso's Dolphin ◽

Social Units ◽

First Time

In this study, we present for the first time a model for the social structure of Risso’s dolphins ( Grampus griseus Cuvier, 1812). Over the period 2004–2006, 1028 Risso’s dolphins were identified at Pico island, Azores. Individuals sighted on 10 or more occasions were included in the analysis of social structure (n = 183). High resighting rates indicate strong site fidelity for at least part of the population. We found that individuals form stable, long-term bonds organised in pairs or in clusters of 3–12 individuals. Social structure is stratified based on age and sex classes, with strong associations between adult males and between adult females. We suggest that clusters form the basic units of Risso’s dolphin society. Thirteen pods consisting solely of adults, likely males, and 3 pods consisting of mother–calf pairs were identified. Males are organised in stable, long-term associations of varying size that occur throughout the complete range of behavioural states observed. For females, associations can be of similar strength, but the time scale may vary depending on the presence of nursing calves. As subadults, associations also occur (pair formation), but are less stable than those observed for adults. We propose a new model for Risso’s dolphin societies known as a stratified social organisation, which differs from the fission–fusion and matrilineal society models.

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Remarks on Echinodermata from the South Central Mediterranean Sea based upon collections made during the MARCOS cruise (10 to 20th April, 2007)

Mediterranean Marine Science ◽

10.12681/mms.109 ◽

2009 ◽

Vol 10 (2) ◽

pp. 63 ◽

Cited By ~ 5

Author(s):

C. MIFSUD ◽

M. TAVIANI ◽

S. STOHR

Keyword(s):

Mediterranean Sea ◽

The South ◽

Central Mediterranean ◽

Management Zone ◽

Maltese Islands ◽

South Central ◽

Central Mediterranean Sea ◽

The Mediterranean ◽

First Time ◽

The Mediterranean Basin

The MARCOS cruise, which took place in the South Central Mediterranean Sea on board the RV ‘Urania’, resulted in the collection of 27 species of Echinodermata from shallow to bathyal depths, many from around Malta (the Fisheries Management Zone). The fauna is represented by common to rare taxa already reported from the Mediterranean with the exception of the amphi-Atlantic ophiuroid Ophiotreta valenciennesi rufescens (Koehler, 1896), recorded from the Mediterranean Basin for the first time. Odontaster mediterraneus (von Marenzeller, 1893) and Luidia sarsi Lutken, 1858 are also first records for the Maltese Islands.

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Cephalopods from the stomachs of a Risso's dolphin (Grampus griseus) from the Mediterranean

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400060094 ◽

1992 ◽

Vol 72 (4) ◽

pp. 861-867 ◽

Cited By ~ 30

Author(s):

M. Würtz ◽

R. Poggi ◽

Malcolm R. Clarke

Keyword(s):

Mediterranean Sea ◽

Calorific Value ◽

Dry Weight ◽

Oceanic Water ◽

Central Mediterranean ◽

Grampus Griseus ◽

Central Mediterranean Sea ◽

Wet Weight ◽

Risso's Dolphin ◽

Ligurian Coast

Cephalopod remains from the stomachs of a Risso's dolphin (Grampus griseus Cuvier, 1812, Cetacea) entangled in a fishing net off the Ligurian coast (central Mediterranean Sea) include squids Ancistroteuthis lichtensteini, Histioteuthis bonnellii, H. reversa and Todarodes sagittatus and the sepiolid Heteroteuthis dispar. All these cephalopods live in oceanic water including water over the steep continental slope where Risso's dolphin is frequently sighted. Histioteuthis reversa contributed 78% of the cephalopods by number, 81% of the wet weight and 73% of the dry weight and calorific value. The total calorific value of the cephalopods represented by lower beaks was 17,300 kj.

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The Paliurus spina-christi dominated vegetation in Europe

Biologia ◽

10.1515/biolog-2015-0100 ◽

2015 ◽

Vol 70 (7) ◽

Cited By ~ 4

Author(s):

Simona Casavecchia ◽

Nello Biscotti ◽

Simone Pesaresi ◽

Edoardo Biondi

Keyword(s):

Eastern Mediterranean ◽

Balkan Peninsula ◽

Central Mediterranean ◽

Bioclimatic Indices ◽

The Balkans ◽

The North ◽

South Central ◽

North Eastern ◽

Phytosociological Relevés ◽

First Time

AbstractThe revision of the Paliurus spina-christi dominated vegetation of Europe is presented here. The study area includes the north-eastern part of Iberian Peninsula and Provence to the west, and spreads through the Apennine Peninsula to the Balkan Peninsula and up to Eastern Mediterranean areas. The phytosociological releves of Paliurus spina-christi dominated vegetation found in the literature for these European territories were gathered together in a phytosociological table. Floristic analysis, cluster analysis, and indirect gradient analysis were performed to determine the similarities and differences between the different Paliurus spina-christi dominated communities and their correlations with the main bioclimatic indices described in the literature. The various analyses highlight the existence of nine different associations (one of which is described here for the first time) that are attributed to different syntaxonomic levels.In the conclusion, a syntaxonomical scheme is proposed that classifies the European vegetation of shrublands in the class Rhamno-Prunetea which includes the class Paliuretea. Currently, we recognized three orders within this class: Prunetalia spinosae for central and south-central Europe; Pyro spinosae-Rubetalia ulmifolii within the Temperate oceanic bioclimate of the sub-Mediterranean variant; Paliuretalia spinae-christi with a central Mediterranean and sub-Mediterranean distribution, that mainly occurs in the central-eastern Mediterranean (Southern Apennine Peninsula) and the Balkans.Finally, a part of the shrub vegetation dominated by Paliurus spina-christi is referred to the class Quercetea ilicis, the order Pistacio lentisci-Rhamnetalia alaterni, the alliance Oleo sylvestris-Ceratonion siliquae and the suballiance Oleo sylvestris- Paliurenion spinae-christi that refers to thermophilous shrub communities that require high edaphic humidity.

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Site fidelity, residency and habitat use of the Risso’s dolphin Grampus griseus in the Gulf of Taranto (Northern Ionian Sea, Central-eastern Mediterranean Sea) by photo-identification

2018 IEEE International Workshop on Metrology for the Sea; Learning to Measure Sea Health Parameters (MetroSea) ◽

10.1109/metrosea.2018.8657847 ◽

2018 ◽

Cited By ~ 2

Author(s):

Roberto Carlucci ◽

Aylin Akkaya Bas ◽

Rosalia Maglietta ◽

Vito Reno ◽

Carmelo Fanizza ◽

...

Keyword(s):

Habitat Use ◽

Mediterranean Sea ◽

Site Fidelity ◽

Eastern Mediterranean ◽

Ionian Sea ◽

Eastern Mediterranean Sea ◽

Photo Identification ◽

Grampus Griseus ◽

Central Eastern ◽

Risso's Dolphin

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Checklist with first records for the Echinoderms of northern Tunisia (central Mediterranean Sea)

Scientia Marina ◽

10.3989/scimar.04899.19a ◽

2019 ◽

Vol 83 (3) ◽

pp. 277

Author(s):

Hayfa Chammem ◽

Jamila Ben Souissi ◽

Angel Pérez-Ruzafa

Keyword(s):

Mediterranean Sea ◽

Marine Biodiversity ◽

Marine Waters ◽

Central Mediterranean ◽

Northern Tunisia ◽

Strait Of Sicily ◽

Central Mediterranean Sea ◽

Region Data ◽

First Time ◽

New Occurrences

Tunisia occupies a strategic biogeographic position in the Mediterranean Sea and the Strait of Sicily is considered a biogeographical boundary that separates the eastern and western basins. Despite the importance of marine biodiversity in Tunisia, the few studies of Echinodermata fauna in this region data from long ago. In order to update and produce a validated checklist of the echinoderms that occur in northern Tunisia, a study of this phylum was carried out between 2012 and 2016. Forty-five species were inventoried and distributed into the five living Echinodermata classes (Crinoidea, Asteroidea, Ophiuroidea, Echinoidea and Holothuroidea). New occurrences of four species from Tunisian marine waters [Asterina pancerii (Gasco, 1876), Luidia atlantidea (Madsen, 1950), Ophiactis virens (Sars, 1859) and Leptopentacta tergestina (Sars, 1857)], are cited and discussed here for the first time.

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