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Le continent de plastique existe-t-il vraiment ?

Map Shows Vast Regions of Ocean Are Warmer.

Marine microworlds: the private life of plankton.

New study confirms the oceans are warming rapidly.

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.

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.

International marine scientists today warned it will be vital to protect key marine turtle nesting grounds and areas that may be suitable for turtle nesting in the future to ensure that the marine reptiles have a better chance of withstanding climate change.

The role played by oceans - not only the Atlantic and Pacific, but also the Indian Ocean - in South American climate variability is one of the topics researched by Marcelo BARREIRO, Head of Atmospheric Sciences at Uruguay's University of the Republic (UDELAR).

Russia will strengthen its naval forces in the Arctic and Atlantic as a response to Nato activities close to Russia's borders, the Kremlin says.

Russia will strengthen its naval forces in the Arctic and Atlantic as a response to Nato activities close to Russia's borders, the Kremlin says.

Global conservation priorities for marine turtles.

Under the surface.

Under the surface.

How the Hell Did Three Pacific Reef Sharks Wind Up Off the Coast of Brazil?

For better or worse, oceanographic and meteorological forces in the Indian Ocean seem to be preventing plastic from accumulating to form a garbage patch.

- Diego CARDEÑOSA uses DNA to track and monitor the shark fin trade. 99.8 percent of silky shark fins that were sampled originated from the Indo-Pacific Ocean. - This study emphasizes the need for increased monitoring in this region. - The long-term goal of CARDEÑOSA research is to provide information about where shark fins originate in order to better direct more concentrated shark conservation efforts and fisheries management.

The values used for natural mortality (M) are very influential in stock assessment models, affecting model outcomes and management advice. Natural mortality is one of the most difficult demographic parameters to estimate, and there is often limited information about the true levels. Here, we summarise the evidence used to estimate natural mortality at age for the four main stocks of yellowfin tuna (Indian, Western and Central Pacific, Eastern Pacific, and Atlantic Oceans), including catch curves, tagging experiments, and maximum observed age. We identify important issues for estimating M such as variation with age linked to size, maturity state or senescence, and highlight information gaps. We describe the history of natural mortality values used in stock assessments by the tuna Regional Fisheries Management Organisations responsible for managing each stock and assess the evidence supporting these values. In June 2021, an online meeting was held by the Center for the Advancement of Population Assessment Methodology (CAPAM), to provide advice and guidance on practices for modelling natural mortality in fishery assessments. Based on approaches presented and discussed at the meeting, we develop a range of yellowfin tuna natural mortality estimates for each stock. We also recommend future research to improve these estimates of natural mortality.

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.