Group items tagged

Voici le ver Bobbit, l'un des plus terrifiants prédateurs des océans.

Voici le ver Bobbit, l'un des plus terrifiants prédateurs des océans.

Le continent de plastique existe-t-il vraiment ?

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.

Map Shows Vast Regions of Ocean Are Warmer.

Marine microworlds: the private life of plankton.

New study confirms the oceans are warming rapidly.

The three skippers in the Vendee Globe solo round the world race who are having to avoid the worst of the violent Southern Ocean storm all are deploying different strategies. Two, Jean LE CAM in eighth and seventh placed Jean-Pierre DICK are headed in different directions as they outrun the worst of the winds nearest the centre of the low, while Yann ELIES in sixth has hove to and slowed right down - to just two or three knots at times - to hold a position which should ensure the strongest winds pass to his north.

10 questions fréquentes sur le tsunami.

Somali pirates seize Greek tanker.

El Niño, one of three strongest recorded, brings high drought risk for Australia.

El Niño, one of three strongest recorded, brings high drought risk for Australia.

When humpback whales shift their distribution and behaviour, it can lead to unexpected human encounters and new challenges.

New research highlights both natural climate variability, warming temperatures.

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).

The history of a new type of crab, nicknamed 'The Hoff' because of its hairy chest, has been revealed for the first time.

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.