16SrDNA Pyrosequencing of the Mediterranean Gorgonian Paramuricea clavata Reveals a Link among Alterations in Bacterial Holobiont Members, Anthropogenic Influence and Disease Outbreaks

Understanding the resilience of temperate reefs to climate change requires exploring the recovery capacity of their habitat-forming species from recurrent marine heatwaves (MHWs). Here, we show that, in a Mediterranean highly enforced marine protected area established more than 40 years ago, habitat-forming octocoral populations that were first affected by a severe MHW in 2003 have not recovered after 15 years. Contrarily, they have followed collapse trajectories that have brought them to the brink of local ecological extinction. Since 2003, impacted populations of the red gorgonian Paramuricea clavata (Risso, 1826) and the red coral Corallium rubrum (Linnaeus, 1758) have followed different trends in terms of size structure, but a similar progressive reduction in density and biomass. Concurrently, recurrent MHWs were observed in the area during the 2003–2018 study period, which may have hindered populations recovery. The studied octocorals play a unique habitat-forming role in the coralligenous assemblages (i.e. reefs endemic to the Mediterranean Sea home to approximately 10% of its species). Therefore, our results underpin the great risk that recurrent MHWs pose for the long-term integrity and functioning of these emblematic temperate reefs.

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Thread-like tentacles in the Mediterranean corals Paramuricea clavata and Corallium rubrum

Mediterranean Marine Science ◽

10.12681/mms.13807 ◽

2018 ◽

Cited By ~ 1

Author(s):

PABLO J LOPEZ-GONZALEZ ◽

LORENZO BRAMANTI ◽

PABLO ESCRIBANO-ÁLVAREZ ◽

MARIA-CARLA BENEDETTI ◽

IRENE MARTÍNEZ-BARALDÉS ◽

...

Keyword(s):

Aggressive Behavior ◽

Corallium Rubrum ◽

Paramuricea Clavata ◽

The Mediterranean

The occurrence of modified tentacles (i.e. thread-like tentacles) in the Mediterranean octocorals Paramuricea clavata and Corallium rubrum is reported. Colonies of four species of Mediterranean gorgonians were maintained in aquarium conditions for more than 5 months. The development of thread-like tentacles has been observed only in two of the four species. The presence of modified tentacles in other cnidarians has been usually associated with defensive/aggressive behavior. Our observations showed that thread-like tentacles in P. clavata and C. rubrum can also be used for feeding.

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Anthropogenic effects on reproductive effort and allocation of energy reserves in the Mediterranean octocoral Paramuricea clavata

Marine Ecology Progress Series ◽

10.3354/meps09521 ◽

2012 ◽

Vol 449 ◽

pp. 161-172 ◽

Cited By ~ 25

Author(s):

G Tsounis ◽

L Martinez ◽

L Bramanti ◽

N Viladrich ◽

JM Gili ◽

...

Keyword(s):

Reproductive Effort ◽

Anthropogenic Effects ◽

Energy Reserves ◽

Paramuricea Clavata ◽

The Mediterranean

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The Genome Sequence of the Octocoral Paramuricea clavata – A Key Resource To Study the Impact of Climate Change in the Mediterranean

G3 Genes|Genome|Genetics ◽

10.1534/g3.120.401371 ◽

2020 ◽

Vol 10 (9) ◽

pp. 2941-2952

Author(s):

Jean-Baptiste Ledoux ◽

Fernando Cruz ◽

Jèssica Gómez-Garrido ◽

Regina Antoni ◽

Julie Blanc ◽

...

Keyword(s):

Evolutionary Ecology ◽

De Novo ◽

Western Mediterranean ◽

De Novo Genome Assembly ◽

Protein Coding ◽

The North ◽

Paramuricea Clavata ◽

The Mediterranean ◽

Differential Responses ◽

The Impact

Abstract The octocoral, Paramuricea clavata, is a habitat-forming anthozoan with a key ecological role in rocky benthic and biodiversity-rich communities in the Mediterranean and Eastern Atlantic. Shallow populations of P. clavata in the North-Western Mediterranean are severely affected by warming-induced mass mortality events (MMEs). These MMEs have differentially impacted individuals and populations of P. clavata (i.e., varied levels of tissue necrosis and mortality rates) over thousands of kilometers of coastal areas. The eco-evolutionary processes, including genetic factors, contributing to these differential responses remain to be characterized. Here, we sequenced a P. clavata individual with short and long read technologies, producing 169.98 Gb of Illumina paired-end and 3.55 Gb of Oxford Nanopore Technologies (ONT) reads. We obtained a de novo genome assembly accounting for 607 Mb in 64,145 scaffolds. The contig and scaffold N50s are 19.15 Kb and 23.92 Kb, respectively. Despite of the low contiguity of the assembly, its gene completeness is relatively high, including 75.8% complete and 9.4% fragmented genes out of the 978 metazoan genes contained in the metazoa_odb9 database. A total of 62,652 protein-coding genes have been annotated. This assembly is one of the few octocoral genomes currently available. This is undoubtedly a valuable resource for characterizing the genetic bases of the differential responses to thermal stress and for the identification of thermo-resistant individuals and populations. Overall, having the genome of P. clavata will facilitate studies of various aspects of its evolutionary ecology and elaboration of effective conservation plans such as active restoration to overcome the threats of global change.

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SfM-Based Method to Assess Gorgonian Forests (Paramuricea clavata (Cnidaria, Octocorallia))

Remote Sensing ◽

10.3390/rs10071154 ◽

2018 ◽

Vol 10 (7) ◽

pp. 1154 ◽

Cited By ~ 11

Author(s):

Marco Palma ◽

Monica Casado ◽

Ubaldo Pantaleo ◽

Gaia Pavoni ◽

Daniela Pica ◽

...

Keyword(s):

Population Structure ◽

Protected Area ◽

Marine Protected Area ◽

Methodological Approach ◽

Dry Weight ◽

Marine Habitats ◽

Paramuricea Clavata ◽

Maximal Height ◽

Maximal Width ◽

The Mediterranean

Animal forests promote marine habitats morphological complexity and functioning. The red gorgonian, Paramuricea clavata, is a key structuring species of the Mediterranean coralligenous habitat and an indicator species of climate effects on habitat functioning. P. clavata metrics such as population structure, morphology and biomass inform on the overall health of coralligenous habitats, but the estimation of these metrics is time and cost consuming, and often requires destructive sampling. As a consequence, the implementation of long-term and wide-area monitoring programmes is limited. This study proposes a novel and transferable Structure from Motion (SfM) based method for the estimation of gorgonian population structure (i.e., maximal height, density, abundance), morphometries (i.e., maximal width, fan surface) and biomass (i.e., coenenchymal Dry Weight, Ash Free Dried Weight). The method includes the estimation of a novel metric (3D canopy surface) describing the gorgonian forest as a mosaic of planes generated by fitting multiple 5 cm × 5 cm facets to a SfM generated point cloud. The performance of the method is assessed for two different cameras (GoPro Hero4 and Sony NEX7). Results showed that for highly dense populations (17 colonies/m2), the SfM-method had lower accuracies in estimating the gorgonians density for both cameras (60% to 89%) than for medium to low density populations (14 and 7 colonies/m2) (71% to 100%). Results for the validation of the method showed that the correlation between ground truth and SfM estimates for maximal height, maximal width and fan surface were between R2 = 0.63 and R2 = 0.9, and R2 = 0.99 for coenenchymal surface estimation. The methodological approach was used to estimate the biomass of the gorgonian population within the study area and across the coralligenous habitat between −25 to −40 m depth in the Portofino Marine Protected Area. For that purpose, the coenenchymal surface of sampled colonies was obtained and used for the calculations. Results showed biomass values of dry weight and ash free dry weight of 220 g and 32 g for the studied area and to 365 kg and 55 Kg for the coralligenous habitat in the Marine Protected Area. This study highlighted the feasibility of the methodology for the quantification of P. clavata metrics as well as the potential of the SfM-method to improve current predictions of the status of the coralligenous habitat in the Mediterranean sea and overall management of threatened ecosystems.

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Mediterranean Aquaculture in a Changing Climate: Temperature Effects on Pathogens and Diseases of Three Farmed Fish Species

Pathogens ◽

10.3390/pathogens10091205 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1205

Author(s):

Maria Chiara Cascarano ◽

Orestis Stavrakidis-Zachou ◽

Ivona Mladineo ◽

Kim D. Thompson ◽

Nikos Papandroulakis ◽

...

Keyword(s):

Climate Change ◽

Mediterranean Sea ◽

Fish Species ◽

Sparus Aurata ◽

Dicentrarchus Labrax ◽

Disease Outbreaks ◽

Gilthead Seabream ◽

Farmed Fish ◽

Fish Welfare ◽

The Mediterranean

Climate change is expected to have a drastic effect on aquaculture worldwide. As we move forward with the agenda to increase and diversify aquaculture production, rising temperatures will have a progressively relevant impact on fish farming, linked to a multitude of issues associated with fish welfare. Temperature affects the physiology of both fish and pathogens, and has the potential to lead to significant increases in disease outbreaks within aquaculture systems, resulting in severe financial impacts. Significant shifts in future temperature regimes are projected for the Mediterranean Sea. We therefore aim to review and discuss the existing knowledge relating to disease outbreaks in the context of climate change in Mediterranean finfish aquaculture. The objective is to describe the effects of temperature on the physiology of both fish and pathogens, and moreover to list and discuss the principal diseases of the three main fish species farmed in the Mediterranean, namely gilthead seabream (Sparus aurata), European seabass (Dicentrarchus labrax), and meagre (Argyrosomus regius). We will attempt to link the pathology of each disease to a specific temperature range, while discussing potential future disease threats associated with the available climate change trends for the Mediterranean Sea.

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