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Le continent de plastique existe-t-il vraiment ?

An international study led by The University of Western Australia has found that temperate marine ecosystems dominated by marine forests are collapsing into flattened seascapes of short turf algae across the globe.

With piracy spreading along large swathes of Africa's coast, shipping firms and governments are deploying hi-tech weapons in the fight against the raiders.

With piracy spreading along large swathes of Africa's coast, shipping firms and governments are deploying hi-tech weapons in the fight against the raiders.

Fresh Piracy Off West Africa Highlights Link to Overfishing.

Whales and human-related activities overlap in African waters

Conrad HUMPHREYS revient sur son démâtage.

Pêche: l'Afrique bientôt importatrice de poissons?

Floating Ocean Thermal Energy Conversion Device Concept Revealed.

Figures of the week: Piracy increasing in the Gulf of Guinea.

Scientists know that low-oxygen dead zones are growing worldwide. New research sheds light on what that will mean for estuary systems if trends continue.

Hungry Mice Are Attacking and Killing Adult Albatrosses.

A study has uncovered the secret to why endangered whale sharks gather on mass at just a handful of locations around the world.

Nigeria wants to adopt Kenya's strategy in bolstering maritime security.

Brussels declares Saint Vincent and the Grenadines and the Comoros as non-cooperating countries

Transat Jacques VABRE. Le bateau leader en Class40 a démâté !

A new study highlights that sub-Antarctic seabirds are most at risk from unsustainable fishing during the southern hemisphere winter and in the south Atlantic and Southwest Indian Oceans. The link between fishing and the steep decline in seabird populations is well established, but the identification of problem 'hotspots' will better help agencies to conserve a number of threatened species. The study is published in the Journal of Applied Ecology this week (22 May).

With no working computers Fabrice AMEDEO Abandons, DALIN's margin is halved, MERRON, SHIRAISHI Cross Good Hope.

Paralicella tenuipes CHEVREUX, 1908 and Paralicella caperesca SCHULENBERGER and BARNARD, 1976 are known as widely distributed deep-sea scavenging amphipods. Some recent studies based on genetic data indicated the presence of high intraspecific variation of P. caperesca suggesting it is a species complex. Based on published molecular data from the Pacific and Indian oceans and new material obtained from the North and South Atlantic, we integrated the knowledge on the intraspecific variation and species distribution of the two nominal taxa. The study included analysis of three genes (COI, 16S rRNA, 28S rRNA) and revealed the existence of a single Molecular Operational Taxonomic Unit (MOTU) within P. tenuipes and six different MOTUs forming P. caperesca. The distribution pattern of the recognized lineages varied with three (P. tenuipes, MOTU 1 and MOTU 5 of P. caperesca) being widely distributed. There was evidence of contemporary population connectivity expressed by the share of the same COI haplotypes by individuals from very distant localities. At the same time no signal of recent demographic changes was observed within the studied taxa. The time-calibrated phylogeny suggested the emergence of species to be at the time of Mesozoic/Cenozoic transition that may be associated with global changes of the ocean circulation and deep sea water cooling.

Although submarine canyons are internationally recognized as sensitive ecosystems and reported to be biological hotspots, regional studies are required to validate this consensus. To this end, hydrographic and benthic biodiversity data were collected during three cruises (2016-2017) to provide insights on the benthic patterns within South African canyon and non-canyon offshore areas. A total of 25 stations, sampled at 200-1000 m depth range, form the basis of the multivariate analysis. Diversity gradients were calculated and then differences were compared across substrate types and depth zones represented within 12 canyon and 13 non-canyon stations. Significant differences in both substrate and depth were evident, despite measures being highly variable. This observation of varying diversity in different substrates is in line with previous studies. No clear pattern was observed for species diversity (delta+). However, non-canyon stations overall showed a higher diversity in comparison to canyon stations. A notable peak in diversity is observed in canyon areas in the 401-500 m depth zone. Species richness followed an opposing pattern, as it decreased with depth and was consistently higher in canyon areas. These results align with the well-defined influence of depth-related variables on the distribution of taxonomic groups and the substrate available, at various scales. The eutrophic characteristic of the Benguela region may have attributed to the insignificant diversity differences between canyon and non-canyon stations. To assess the benthic species structure in canyon and non-canyon areas, we converted the 108 benthic species into a gamma+ matrix. We then modelled the biological response to predictor variables (substrate and depth). Although the canyon and non-canyon areas have an overlapping species composition, the main effects (canyon vs. non-canyon, depth, and substrate) showed significant differences. Thirteen species were characteristic of canyon areas, whilst