Deep-water red coral from the island of Sardinia (north-western Mediterranean): a local example of sustainable management

2013 ◽  
Vol 64 (8) ◽  
pp. 706 ◽  
Author(s):  
Maria Cristina Follesa ◽  
Rita Cannas ◽  
Alessandro Cau ◽  
Claudia Pedoni ◽  
Paola Pesci ◽  
...  

Since 1979, red coral harvesting in Sardinia has been regulated by regional laws. The regulations, including a minimum take size of 10-mm basal diameter, were imposed to limit and control harvesting. Our study indicated that >75% of the red coral colonies harvested in 2007–08 in the north-western coast were above the legal minimum size for exploitation. Moreover, extensive surveys with remotely operated vehicles allowed us to document the real structure of wild populations. Large colonies (>10 mm) represented a big portion of the population (~38% of the total), suggesting that harvesting effort did not affect yet the maximum size of colonies. All these results seem to be confirmed by the application of the model of Beverton and Holt. This model shows that the fishery of red coral in Sardinia reaches its maximum yield at an age at first capture of 20 years, an age significantly lower than the average age of 30 years calculated for the colonies actually harvested in the Sardinian coast. Our data confirmed that the measures enacted in the Sardinian regulations provide for an adequate management of this resource and, in addition, can represent a guideline for other countries that still lack a valid management plan.

2014 ◽  
Vol 161 (5) ◽  
pp. 1015-1026 ◽  
Author(s):  
L. Bramanti ◽  
I. Vielmini ◽  
S. Rossi ◽  
G. Tsounis ◽  
M. Iannelli ◽  
...  

2012 ◽  
Vol 92 (8) ◽  
pp. 1799-1808 ◽  
Author(s):  
Alexandre Gannier ◽  
Estelle Petiau ◽  
Violaine Dulau ◽  
Luke Rendell

Oceanic odontocetes rely on echolocation to forage on pelagic or benthic prey, but their feeding ecology is difficult to study. We studied sperm whale foraging dives during summer in the north-western Mediterranean, using visual and passive acoustic observations. Clicking and creaking activities were recorded during dives of focal whales, at distances <3000 m using a towed hydrophone and DAT recorder. A total of 52 sperm whales were recorded over at least one full dive cycle. Data were obtained for 156 complete dives in total, including sequences of up to nine consecutive dives. Various dive and environmental variables were entered in multiple linear regression and principal components analysis, as well as estimated mass of whales. Creak rate was 0.80 creak/minute on average, with moderate variance. Bigger whales tended to dive longer at greater depths (as suggested by ascent durations), and emitted more creaks during a dive: 20.2 creaks/dive on average for individuals <24 tons, compared to 25.6 creaks/dive for animals >24 tons of estimated mass. For individual whales, creak rates did not vary significantly with size (range 0.78–0.80 creak/minute), but decreased with time of the day, and increased for shorter foraging phases. For different dives, higher creak rates were also observed earlier in the day, and linked to shorter foraging phases and surface durations. Although the exact significance of creak emissions (i.e. foraging attempt or prey capture) is not precisely determined, creak rates may be reliably used to quantify sperm whale foraging when single animal dives can be followed acoustically.


Chemosphere ◽  
2007 ◽  
Vol 66 (7) ◽  
pp. 1230-1242 ◽  
Author(s):  
Inês Lima ◽  
Susana M. Moreira ◽  
Jaime Rendón-Von Osten ◽  
Amadeu M.V.M. Soares ◽  
Lúcia Guilhermino

2010 ◽  
Vol 7 (3) ◽  
pp. 809-826 ◽  
Author(s):  
E. Ternon ◽  
C. Guieu ◽  
M.-D. Loÿe-Pilot ◽  
N. Leblond ◽  
E. Bosc ◽  
...  

Abstract. Simultaneous measurements of atmospheric deposition and of sinking particles at 200 and 1000 m depth, were performed in the Ligurian Sea (North-Western Mediterranean) between 2003 and 2007, along with phytoplanktonic activity derived from satellite images. Atmospheric deposition of Saharan dust particles was very irregular and confirmed the importance of sporadic high magnitude events over the annual average (11.4 g m−2 yr−1 for the 4 years). The average marine total mass flux was 31 g m−2 yr−1, the larger fraction being the lithogenic one (~37%). The marine total mass flux displayed a seasonal pattern with a maximum in winter, occurring before the onset of the spring bloom. The highest POC fluxes did not occur during the spring bloom nor could they be directly related to any noticeable increase in the surface phytoplanktonic biomass. Over the 4 years of the study, the strongest POC fluxes were concomitant with large increases of the lithogenic marine flux, which had originated from either recent Saharan fallout events (February 2004 and August 2005), from "old" Saharan dust "stored" in the upper water column layer (March 2003 and February 2005), or alternatively from lithogenic material originating from Ligurian riverine flooding (December 2003, Arno, Roya and Var rivers). Those associated export fluxes defined as "lithogenic events", are believed to result from a combination of forcing (winter mixing or Saharan events, in particular extreme ones), biological (zooplankton) activity, and also organic-mineral aggregation inducing a ballast effect. By fertilising the surface layer, mixed Saharan dust events were shown to be able to induce "lithogenic events" during the stratification period. These events would be more efficient in transferring POC to the deeper layers than the spring bloom itself. The extreme Saharan event of February 2004 exported ~45% of the total annual POC, compared to an average of ~25% for the bloom period. This emphasises the role played by these "lithogenic events", and in particular those that are induced by the more extreme Saharan events, in the carbon export efficiency in the North-western Mediterranean Sea.


ZooKeys ◽  
2019 ◽  
Vol 838 ◽  
pp. 71-84
Author(s):  
Céline Labrune ◽  
Nicolas Lavesque ◽  
Paulo Bonifácio ◽  
Pat Hutchings

A new species of Terebellidae, Pistacolinisp. n., has been identified from the harbour of Banyuls-sur-Mer, north-western Mediterranean Sea. This new species was found in very high densities, exclusively in gravelly sand deposited manually, and was not found in the original source habitat of the gravel. This species is characterized by the colour of the ventral shields with pinkish anterior part and a blood red posterior part in live specimens, a pair of unequal-sized plumose branchiae inserted on segment II and anterior thoracic neuropodia with long-handled uncini. The presence of long-handled uncini even in the smallest specimens constitutes the major difference between Pistacolinisp. n. and other Pista species with a single pair of branchiae such as P.lornensis and P.bansei.


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