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Showing posts with the label Oceans

New research shows: More rare, endangered sharks are dying in the worldwide trade in shark fins than earlier feared..

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by Larry Powell   The "Grey Nurse" or "Sand Tiger," shark (  Carcharias taurus ), a coastal species on the ICU's Red List as  critically endangered. A public domain photo by Richard Ling.  Here's how sharks are "finned." After hauling them aboard their vessels, the fishermen cut off their fins, then toss them back into the ocean. Still alive, they sink to the bottom where they're either eaten by other predators or die of suffocation.  About 100 million sharks are believed to be taken by fishers each year, most of them for their fins alone.  It's an industry estimated to be worth US$400 million a year.  The blue shark (Prionaceglauca). Photo by Mark Conlin/NMFS. If one were to believe official trade records over the past twenty years, most fins traded on world markets have come from more abundant "pelagic" species (ones which live in the open ocean) like the blue shark (above).    Using advanced techniques in barcoding and genetic

Arctic ocean moorings shed light on winter sea ice loss

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Science Daily A table iceberg in the Norwegian Arctic. Such icebergs are rare as they calve from shelf ice, which is also rare. They're normally a typical form of iceberg in the Antarctic. This one is about 12m high and about half the size of a soccer field. Photo by Andreas Weith. The eastern Arctic Ocean's winter ice grew less than half as much as normal during the past decade, due to the growing influence of heat from the ocean's interior, researchers have found. Story here.

There is at least 10 times more plastic in the Atlantic than previously thought

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Science News  "Seal trapped in plastic pollution"   by  tedxgp2   Scientists measured 12-21 million tons of three of the most common types of plastic in the top 200 meters of the Atlantic. By assuming the concentration of plastic in the whole Atlantic is the same as that measured at 200 meters deep, the scientists estimated there is around 200 million tons of three of the most common types of plastic alone. Compare this to the previously estimated figure of 17 million.  Details here.

Measuring ecosystem disruption caused by marine heatwaves

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 Nature Above, healthy bull kelp. Below, bull kelp degraded by a marine heatwave. DeWikiMan Marine heatwaves can displace thermal habitats by tens to thousands of kilometres, reports a study in Nature this week. This displacement represents the distance that an organism would have to travel to escape potentially stressful temperatures. The findings open new avenues of research to understand the potential impacts of anomalously warm ocean temperatures on marine species. Marine heatwaves are distinct periods of unusually warm ocean temperatures that can cause dramatic changes to ocean ecosystems, as inhabitants find themselves in waters that are warmer than they are accustomed to. Much of the research into these events focuses on the local impact to species such as corals, but does not take into account mobile organisms (fish, for example) that can travel to find their preferred conditions. To understand how species may have to redistribute under marine heatwave conditio

Rapidly warming oceans have left many northern marine mammals swimming in troubled waters. But perhaps none more so than that strange and mysterious "unicorn of the sea," the narwhal.

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by Larry Powell Narwhals are cetaceans, a family of marine mammals which includes whales and dolphins. Most are found in Canada's Baffin Bay and Davis Strait, in the high Arctic and Atlantic Arctic. Others live off Greenland, Norway and Russia. Many spend several months over winter, beneath the ice-pack, feeding on fish, squid and shrimp and their summers in more open water. It's believed they're capable of diving as deep as 15 hundred meters and holding their breath for an astonishing 25 minutes!  A pod "breaches" through an opening in the sea-ice.  A US Fish &  Wildlife Service photo.   They can weigh up to two thousand kilograms and reach a length of about five meters. They're much larger than some dolphin species, but tiny compared to the mighty blue whale. Many migrate along the ice's edge some 17 hundred kilometres from Canada to Russia. The males grow long, spiral tusks - actually overgrown teeth - that can protrude up t

Toxic Tides

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One of the biggest challenges facing the aquaculture industry everywhere, is  Lepeophtheirus salmonis , the sea-louse.    Sea lice,   Lepeophtheirus salmonis,  on farmed Atlantic salmon, New Brunswick, CA. Photo by 7Barrym0re It's a parasite which attacks both farmed and wild salmon (above), causing lesions and infections which stunt their growth. But t he costs of de-lousing are high. And so are the losses suffered by the industry in the marketplace.  Many lice can actually kill many fish. To fight back, the fish-farmers dump pesticides into the waters (below). But, because they’re released directly into the environment, they not only kill the lice, but place beneficial, “non-target” organisms at risk, too. And several of these live in the open ocean, beyond the confines of the  farms. This image shows how industry applies pesticides within their operations. The latest (but not the only) cautionary tale about the wisdom of this practise,   has just

Like Adding'Five to Six Hiroshima Bombs of Heat Each Second,' Study Shows Oceans Warming at Record Rate

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CommonDreams "If you want to understand global warming, you have to measure ocean warming." Story here.

Marine life, fisheries increasingly threatened as the ocean loses oxygen – IUCN report

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International Union for the Conservation of Nature The Daggernose shark, one of several larger species considered especially vulnerable. A NOAA rendering. The loss of oxygen from the world’s ocean is increasingly threatening fish species and disrupting ecosystems, a   new IUCN report   warns. Ocean oxygen loss, driven by climate change and nutrient pollution, is a growing menace to fisheries and species such as tuna, marlin and sharks, according to the report released today at the UN Climate Change conference in Madrid.

Study counts 1.8 million pieces of trash at the bottom of Canada's Bay of Fundy

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The National Observer Daniels Flat (Bay of Fundy) A survey estimates more than 1.8 million pieces of garbage are strewn over the bottom of the Bay of Fundy, prompting concerns about potential harm to marine life. Story here.

Microplastics found in oysters, clams on Oregon coast, study finds. (Last year, Canadian scientists discovered high levels of microplastics in B.C.’s oyster beds). Is our clothing to blame?

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EurekAlert Pacific oysters, farmed in the U.S. Photo by NOAA. Tiny threads of plastics are showing up in Pacific oysters and razor clams along the Oregon coast -- and the yoga pants, fleece jackets, and sweat-wicking clothing that Pacific Northwesterners love to wear are a source of that pollution, according to a new Portland State University study. Story here. RELATED: More bad news for the world’s oceans - out of Canada!

The Amazon River: A Major Source of Organic Plastic Additives to the Tropical North Atlantic?

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Environmental Science & Technology The Amazon empties into the Atlantic. "Flick"  Coordenação-Geral de Observação da Terra/INPE Dissolved surface water concentrations of two important families of plastic additives were found in remarkably high concentrations in the Amazon river plume. Story here.

Why fish ARE getting smaller (Video)

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Ban oil, gas, bottom trawling in CANADA'S marine protected areas, panel urges

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THE STAR Image by NOAA. --> A panel that has spent the year studying marine protected areas (MPAs) in Canada says no oil and gas development, seabed mining, or bottom-trawling fishing should be allowed within their boundaries. More here. RELATED: New research finds that “marine reserves” – tracts of ocean where fishing is banned – are protecting fish, the coral reefs where they live and vast undersea "gardens," a lot more than once thought. By Larry Powell.

Industrial fishing behind plummeting shark numbers

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Science News Research finds marine predators are significantly smaller and much rarer in areas closer to people. Story here. An ocean "white-tip" shark. Photo by NOAA.

Thirty years of unique data reveal what's really killing coral reefs

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Science News Study is world's longest record of reactive nutrients, alga concentrations for coral reefs.  Story here. Bleached coral. Photo by NOAA.