Life without light [video]
The latest blog from BBC Earth takes a look into the diverse life forms that not only survive, but thrive in the darkest depths of our planet. Without sunlight, life on Earth would not exist. Every organism that has evolved on the surface of our planet has received energy either directly or indirectly from the sun. Even creatures that lie at the depths of our oceans and have never felt the sun’s rays, not only survive but can actually flourish thanks to solar energy. 120 kilometres off of the Californian coast at a depth of 1,250m a diverse ecosystem is thriving in the darkness. Rising up 2280 metres from the seafloor, the Davidson Seamount, an underwater mountain, is an ‘oasis in the deep’.
Thought to have formed between 9 and 15 million years ago from volcanic eruptions, the ancient seamount is home to some of the slowest growing communities in the ocean. For example Paragorgia arborea more commonly known as pink bubblegum coral, grows to over three metres in height and is over 100 years old. But how has this seamount managed to sustain more biodiversity with a higher species count than that of the neighbouring seafloor? Its elevated position creates complex current patterns which influences what can live there. The mountain provides a place for species, such as coral, to attach to it which in turn provide food and shelter for other species. Due to these unique conditions seamounts demonstrate a high degree of endemism. Much of the deep sea is fed by the "compost" or “marine snow” from the upper sunlit portions of the sea. As plants and animals at the surface die and decay, they fall toward the sea floor. This snow provides carbon and nitrogen to feed many of the scavengers in the deep sea; testament to the fact that the sun’s rays touch far beyond where they can be seen. But what happens when there are no nutrient-rich currents to feed from? No organic material falling down from above? Or when the extreme conditions make life almost impossible? Over the last 30 years, researchers have discovered deep sea-ecosystems that live independently of the sun’s energy. These communities survive by utilising chemical rather than solar energy. Deep-sea organisms such as mussels, shrimps and squat lobsters host methane fixing bacteria, which convert the chemical energy from methane bubbling out of the sea bed into nutrients.
In this remarkable video from BBC Earth’s Life series, David Attenborough shows us exactly how an assumed barren seabed, became an abundant source of food and life.
These extremophiles have found a way to survive by utilising the energy source which is most abundant to them, begging the question: If life has been found to flourish in even the darkest, saltiest, most inhospitable places where might we find it next? The search continues…
U.S., 3 other countries oppose commercial whaling
The United States, Australia, the Netherlands and New Zealand have voiced their opposition to commercial whaling, expressing disappointment about the recent departure of a Japanese whaling fleet for the Southern Ocean and denouncing any actions that imperil human life. In a joint statement, the governments of the four countries said they "jointly condemn any actions that imperil human life in the Southern Ocean," as they are "deeply concerned that confrontations in the Southern Ocean will eventually lead to injury or loss of life among protesters, many of whom are nationals of our countries, and whaling crews. We remain resolute in our opposition to commercial whaling, including so-called 'scientific whaling,' in particular in the Southern Ocean Whale Sanctuary established by the International Whaling Commission, and are disappointed about the recent departure of the Japanese whaling fleet for the Southern Ocean," they added. Japan's whaling fleet has set sail for the country's annual hunt in Antarctica, with security beefed up amid international protests.
Damaged Florida Keys coral reefs make amazing recovery
A coral reef damaged when a boat ran aground in the Florida Keys National Marine Sanctuary in 2002 has made an encouraging recovery after a nearly decade-long restoration effort. Hundreds of groundings happen in the sanctuary each year, and conservationists are hoping that this reef-restoration and monitoring effort will help inform future endeavours.
Ribbon seals on track for Endangered Species Act listing, agency says
The National Marine Fisheries Service has renewed plans that may lead to a listing of the ribbon seals under the Endangered Species Act, bringing to three the number of ice-dependent seals in Alaska that could be protected by the act.
Rare sighting of humpback whale off Shetland
Crowds gathered to catch a rare glimpse of a humpback whale spotted off the coast of Shetland. The 50ft whale could be seen swimming within 200m of the shore of the south coast and are a rare sight off Shetland. The last to be spotted, in September 2010, became trapped in creel ropes, freeing itself just as a major operation was being organised.
Supermarket Seafood Survey 2011
The MCS supermarket survey is the benchmark for seafood sustainability in UK supermarkets. Consumers put their faith in supermarkets to source sustainable seafood, and their survey is putting that trust to the test. They sent supermarkets a questionnaire to assess and score them in four key areas: their policy, seafood sales, labelling and consumer information, and sustainability initiatives.
The results have revealed that some retailers are moving in the right direction towards sustainable sourcing, whilst others have made considerably less effort. Marks & Spencer and the Co-operative come out on top with a "Gold" medal standard, with Sainsbury’s and Waitrose picking up "Silver". None of the other major supermarkets reached a level that merited an award, and some refused to take part in the research at all.
Shock as retreat of Arctic sea ice releases deadly greenhouse gas
Dramatic and unprecedented plumes of methane – a greenhouse gas 20 times more potent than carbon dioxide – have been seen bubbling to the surface of the Arctic Ocean by scientists undertaking an extensive survey of the region.
Fish of 'Finding Nemo' Fame May Soon be Found No More
Pixar's wildly popular animated film 'Finding Nemo' gained near universal praise from fans and critics, earned numerous awards and accolades for its stars, and netted parent company Walt Disney Pictures over $860 million in box office revenue - the real losers, it turns out, are the real-life fish it portrayed. According to a new study which examined the extinction risk of the marine animals of 'Nemo' found that one in six species depicted in the film's animated aquatic setting run the risk of meeting a most un-Disney sort of end. Researchers from Simon Fraser University and International Union for Conservation of Nature (IUCN) report that while the health of Earth's ocean ecosystems are in decline, even the most charismatic, memorable marine species are feeling the pinch - and partially because they're popular. As species rise to public awareness through media, like the fish-rich 'Finding Nemo', it's often a boon to conservation efforts. But sometimes, say researchers, it has the opposite effect.
Elephant seal is back - after 18,000-mile jaunt at sea
Satellite tags have tracked a southern elephant seal nicknamed Jackson travelling for a whopping 18,000 miles (29,000 kilometres), the equivalent of going from New York to Sydney and back again. The Wildlife Conservation Society tracked the male seal from December 2010 until last month after conservationists with the group fitted Jackson with a small satellite transmitter on the beach of Admiralty Sound in Tierra del Fuego in southern Chile. The transmitter sends a signal every time the animal surfaces to breathe. Jackson then swam 1,000 miles (1,610 km) north, 400 miles (644 km) west, and 100 miles (160 km) south from the original tagging location, meandering through fjords and venturing past the continental shelf as he foraged for fish and squid. WCS reports that Jackson has returned to Admiralty Sound, the site of the original tagging. Each year, elephant seals haul ashore in colonies to molt and find mates. The satellite transmitter is expected to work until early next year, when it will eventually fall off.
Japanese Whalers Sue Sea Shepherd Activists
Whaling authorities of Japan are taking new measures to combat the militant U.S. environmentalist anti-whaling group, Sea Shepherd - they are taking the group to court. The Institute of Cetacean Research, along with masters of whaling vessels, have filed suit against the Sea Shepherd Conservation Society and their leader, Paul Watson, in an attempt to stop the sometimes violent interference in Japan’s annual whale hunt. This is the first time Japan has pursued legal action against anti-whaling campaigners. The Institute and Kyodo Senpaku, ship-owner, are seeking to obtain court orders from a District Court in Seattle, Washington, that would prevent the Sea Shepherd from engaging in all activities at sea that can cause harm to the crew, and vessels of whaling operations.
Moray Eels Grab Prey With "Alien" Jaws
Much like the fearsome star of the Alien movies, moray eels have a second set of toothed jaws that drag prey into their throats, a new study has found. In a series of experiments, scientists at the University of California, Davis, recently discovered that moray eels possess an extremely mobile set of jaws in their throat that they can project forward into their mouth to aid in feeding. However, unlike the fictitious alien's second mandible, which it menacingly extended toward its prey, the eel's jaws are much more practical.
Acidic oceans threaten fish
Ocean acidification - caused by climate change - looks likely to damage crucial fish stocks. Two studies published today in Nature Climate Change reveal that high carbon dioxide concentrations can cause death and organ damage in very young fish. The work challenges the belief that fish, unlike organisms with shells or exoskeletons made of calcium carbonate, will be safe as marine CO2 levels rise.
Santa Claws! Winter white albino lobster is catch of the day in Dorset
A pure white albino lobster has been caught off the coast of Dorset. The snow-coloured beast was pulled from the sea by a fisherman who couldn't bring himself to eat it and instead handed it to an aquarium. Santa Claws - as he's been named - is now at home at the Sea Life centre in Weymouth, Dorset, where he has turned into a popular attraction. Santa is a one-in-a-million find and has been fortunate to be able to survive into adulthood. He was discovered in a lobster pot and is thought to be about 30-years-old.
Jellyfish swarm shuts down St. Lucie nuclear power plant
A massive influx of jellyfish shut down the St. Lucie nuclear power plant in late August, but it is only now that nuclear regulators, wildlife officials and marine researchers are learning that the event also killed several tons of protected goliath grouper. Jellyfish invasions of this magnitude are rare. Biologists at the plant could recall only three other similar events in the past 30 years.
Tsunami fund 'used for whaling'
Japan has used funds from its tsunami recovery budget to subsidise its controversial annual whaling programme, environmental activists say. Greenpeace says 2.3bn yen ($30m; £19m) from a budget of 12.1 trillion yen is being used to fund extra security. Japanese officials argued when they applied for extra funding that whaling helped coastal communities. The whaling fleet reportedly headed for Antarctic waters this week, though Tokyo has not confirmed the reports. There has been a ban on commercial whaling for 25 years, but Japan catches about 1,000 whales each year in what it says is a scientific research programme.
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