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NOAA scientists are warning that warm ocean temperatures in the tropical Pacific and Indian Oceans could set the stage for major coral bleaching events across the globe in 2015.

NOAA scientists are warning that warm ocean temperatures in the tropical Pacific and Indian Oceans could set the stage for major coral bleaching events across the globe in 2015.

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).

Imagery has become a key tool for assessing deep-sea megafaunal biodiversity, historically based on physical sampling using fishing gears. Image datasets provide quantitative and repeatable estimates, small-scale spatial patterns and habitat descriptions. However, taxon identification from images is challenging and often relies on morphotypes without considering a taxonomic framework. Taxon identification is particularly challenging in regions where the fauna is poorly known and/or highly diverse. Furthermore, the efficiency of imagery and physical sampling may vary among habitat types. Here, we compared biodiversity metrics (alpha and gamma diversity, composition) based on physical sampling (dredging and trawling) and towed-camera still images (1) along the upper continental slope of Papua New Guinea (sedimented slope with wood-falls, a canyon and cold seeps), and (2) on the outer slopes of the volcanic islands of Mayotte, dominated by hard bottoms. The comparison was done on selected taxa (Pisces, Crustacea, Echinoidea, and Asteroidea), which are good candidates for identification from images. Taxonomic identification ranks obtained for the images varied among these taxa (e.g., family/order for fishes, genus for echinoderms). At these ranks, imagery provided a higher taxonomic richness for hard-bottom and complex habitats, partially explained by the poor performance of trawling on these rough substrates. For the same reason, the gamma diversity of Pisces and Crustacea was also higher from images, but no difference was observed for echinoderms. On soft bottoms, physical sampling provided higher alpha and gamma diversity for fishes and crustaceans, but these differences tended to decrease for crustaceans identified to the species/morphospecies level from images. Physical sampling and imagery were selective against some taxa (e.g., according to size or behavior), therefore providing different facets of biodiversity. In addition, specimens collected at a larger scale

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

Giant clams are marine bivalves that inhabit Indo-Pacific coral reefs. The boring giant clam, Tridacna crocea, exhibits bright and conspicuous mantle coloration based on the specialized cells (iridocytes) that generate structural colors. In order to illustrate the coloring mechanism of individual iridocytes, the reflection spectra curve of iridocytes was obtained by a micro-hyperspectral imager. TEM images were obtained to show the inner nanostructures of iridocytes. FDTD simulation was conducted to analyze the relationship between the color of iridocytes and the unique lamellar structure. We found that the laminae in the regular arrangement within cells govern the coloration of individual iridocytes. With the gradual increase of lamellar thickness and spacing, the color of the structure varies from bright violet to orange-red, forming a full visible spectrum. This study provides a new understanding of the various colors produced by individual iridocytes.

The Indo-Pacific warm pool is the warmest ocean in the world and is known as "the global heat engine," which plays an important role in the climate system.

Aluminum and manganese are both key parameters in the GEOTRACES program. Data on dissolved aluminum (dAl) and dissolved manganese (dMn) relative to their geochemical behavior remain limited in the northeastern Indian Ocean (IO; including the Bay of Bengal (BoB) and equatorial Indian Ocean (Eq. IO)). Seawater samples collected in the BoB and Eq. IO during the spring inter-monsoon period (7 March to 9 April) of 2017 were analyzed to investigate the behavior and main processes controlling the distributions of dAl and dMn in the northeastern IO. The average concentrations of dAl and dMn in the mixed layer of the BoB were 16.6 and 6.7 nM, respectively. A modified 1-D box-model equation was utilized to estimate the contributions of different sources to dAl and dMn in the mixed layer. Al released from the desorption of and/or dissolution of the lithogenic sediments discharged by the Ganga-Brahmaputra (G-B) river system predominantly controlled the dAl distributions in the mixed layer of the BoB, while the desorption from the lithogenic sediments only contributed approximately 13%-21% dMn. Additional dMn input from the advection of Andaman Sea water and photo-reduction-dissolution of particulate Mn(IV) contributed more than 60% dMn in the mixed layer of the BoB. dAl and dMn in the surface mixed layer of the Eq. IO were mainly affected by the mixing of dAl- and dMn-enriched BoB surface water and low-dAl, low-dMn southern Arabian Sea surface water. Considering water mass properties and dAl concentrations, the distributions of dAl in the intermediate water (750-1,500 m) of northeastern IO were controlled by the mixing of Red Sea Intermediate Water, Indonesian Intermediate Water, and intermediate water of the BoB. Different from dAl, the apparent oxygen utilization relationship with dMn concentrations indicated that the regeneration of lithogenic particles under hypoxic conditions played a more important role than the remineralization of settling organic particles in co

Fish and other sea creatures will have to travel large distances to survive climate change, international marine scientists have warned. Sea life, particularly in the Indian Ocean, the Western and Eastern Pacific and the subarctic oceans will face growing pressures to adapt or relocate to escape extinction, according to a new study by an international team of scientists published in the journal Science.

The Indian Ocean played a far greater role in driving climate change during the most recent ice age than previously believed and may disrupt climate again in the future. That's according to a new study from The University of Texas at Austin, the findings of which could rewrite established Pacific-centric theories on tropical climate change.

Sea-level rise and wave-driven flooding will negatively impact freshwater resources on many low-lying atoll islands in such a way that many could be uninhabitable in just a few decades.

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

East Asian summer monsoon (EASM) is one of the most dominant climate systems in East Asia. The anomalous EASM can cause the extreme high temperature, flood or drought. And El Niño-Southern Oscillation (ENSO), the dominating mode in the tropical Pacific, is the most important factor affecting EASM. Understanding the processes for interannual to interdecadal variability of EASM-ENSO relationship is crucial.

Lucky winner: why this beach in WA claims the crown of Australia's whitest sand.

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.

Seafloor under the hypothesized East Asian Sea vanished 10 million years ago as surrounding plates swallowed it up, according to new reconstructions of plate tectonics in the Philippine Sea region.

Seafloor under the hypothesized East Asian Sea vanished 10 million years ago as surrounding plates swallowed it up, according to new reconstructions of plate tectonics in the Philippine Sea region.

Study by Plymouth University and Natural History Museum reveals four billion fibres could be littering each square kilometre of the world's deep seas.

Study by Plymouth University and Natural History Museum reveals four billion fibres could be littering each square kilometre of the world's deep seas.

Octopuses are generally loners. Squids often form schools. But cuttlefish (or seacuttles if you will)…they outright just don't get along with one another. In the video below two Giant Australian Cuttlefish males that are bit cranky fight over a female. They are both flashing the characteristic Zebra "Don't F**K With Me" pattern. Make sure you watch after 2 minutes when they really throw down.

Octopuses are generally loners. Squids often form schools. But cuttlefish (or seacuttles if you will)…they outright just don't get along with one another. In the video below two Giant Australian Cuttlefish males that are bit cranky fight over a female. They are both flashing the characteristic Zebra "Don't F**K With Me" pattern. Make sure you watch after 2 minutes when they really throw down.

Australia sees record temperatures for fourth month in a row.

Australia has the third largest marine jurisdiction in the world, a vast ocean territory that contains important natural and biological resources. And it needs protecting.

Australia has the third largest marine jurisdiction in the world, a vast ocean territory that contains important natural and biological resources. And it needs protecting.