by Rebecca Morelle
BBC World Science.
The deepest place in the ocean is teeming with microscopic life, a study suggests.
An international team of scientists found that the very bottom of the Mariana Trench, which lies almost 11km (7 miles) down in the Pacific Ocean, had high levels of microbial activity.
The research is published in the journal Nature Geoscience.
The underwater canyon was once thought to be too hostile an environment for life to exist.
But this study adds to a growing body of evidence that a range of creatures can cope with the near-freezing temperatures, immense pressures and complete darkness.
Dr Robert Turnewitsch, one of the authors of the paper from the Scottish Association for Marine Science, said: “The deepest parts of the deep sea are certainly not dead zones.”
In 2010, the scientists sent an unmanned submersible down into the vast underwater canyon, where it collected samples of the murky sediment that cakes the sea floor.
An analysis of the levels of oxygen in the sample revealed the presence of a large number of microbes.
Dr Turnewitsch explained: “These microbes, they respire as we do. And this oxygen consumption is an indirect measurement of the activity of the community.”
Surprisingly, these primitive, single-celled organisms were twice as active at the bottom of the trench than they were at a nearby 6km-deep (four miles) site.
They were feasting on a plentiful supply of dead plants and creatures that had drifted down from the sea surface, the decomposing matter becoming trapped within the steep walls of the trench.
“The amount of food down there and also the relative freshness of the material is surprisingly high - it seems to be surprisingly nutritious,” said Dr Turnewitsch.
The level of material found at the bottom of the trench was so high that it suggests the Mariana Trench - which is in an area of the ocean known as the Hadal zone - could play a key part in the carbon cycle and therefore in regulating the planet’s climate.
Dr Richard Turnewitsch said: “The fact that large amounts of organic matter that contain the carbon accumulate and are focused in these trenches also means they play an important role in the removal of carbon from the ocean and the overlying atmosphere.
“The Hadal trenches may play a more important role in the global marine carbon cycle than was previously thought.”
— You know, we forget. This life is all about the microbes. Always.
Elasmobranch Ecstasy at CITES!
What a day for Sharks and Manta Rays…all four proposals for Elasmobranch species at CITES were passed today. All elasmobranch species up for debate were voted YES for listing under Appendix II.
The final result will come on Thursday with the final plenary, so the fight isn’t over yet, but a positive result is thought to be very likely.
This will mean that fisheries for these species will be regulated to sustainable trade (not a ban on trade) only.
In 40 years of protecting endangered species trade through CITES, marine species have never had a day like today.This result is unprecedented as elasmobranchs have been shamefully overlooked for decades.
The following species got majority votes for their listing, with Mantas winning across board with a whopping 80%!
Keep your fins crossed for Thursday, but celebrate this significant step forward on this manic elasmobranch Monday for:
- Porbeagle sharks
- Three Hammerhead species
- Oceanic White Tip sharks
- Manta rays
- Sawfish (upgrade to Appendix I - no trade!)
A massive congratulations to all those whose research and hard work went into these proposals (Huzzah for Science!) and to those countries that voted YES!
A Shocking Report on your Seafood: Oceana CEO
Do you know what you are serving your family tonight? If it’s fish there’s a good chance that you don’t.
Today Oceana unveiled its landmark national seafood fraud report, one of the largest of its kind and one that should make consumers sit up and demand change.
Over the past several years Oceana tested 1,215 fish samples from 674 retail outlets in 21 states. DNA testing confirmed that fully one-third of this seafood was mislabeled—that is, what we ordered wasn’t what we got.
No matter where you live, seafood fraud is likely to be an issue. But if you live in Austin, Houston or Boston, it is especially widespread. According to our investigation, almost half of the fish tested in these cities was mislabeled. In Southern California the problem was even worse, with mislabeled fish accounting for more than half (52%) of the seafood we tested! Elsewhere, rates of mislabeling were found to be 39 percent in New York City, 38 percent in Northern California and South Florida, 36 percent in Denver, 35 percent in Kansas City, 32 percent in Chicago, 26 percent in Washington, D.C., 21 percent in Portland and 18 percent in Seattle. Nationwide, sushi restaurants mislabeled their fish 74 percent of the time.
As one of our scientists told me, these findings are disturbing—and they’re disturbing for a few reasons. Not only can seafood fraud rip you off by making you pay more for less expensive fish but it can actually be bad for your health. Our scientists found that some fish that had landed a spot on the FDA’s “DO NOT EAT” list for sensitive groups such as pregnant women and children because of its high mercury content was nonetheless being substituted for safer fish. In New York this meant tilefish disguised as red snapper and halibut, while in South Florida king mackerel became grouper. Elsewhere escolar, an oily fish that is known for its purgative effects in some consumers, was substituted 84% of the time for white tuna
If that wasn’t bad enough, mislabeling can be harmful to the oceans as well. By disguising one species as another, it can be nearly impossible for consumers to make responsible decisions to avoid eating overfished species.
So what can you do about it? Right now the United States imports more than 90 percent of the seafood it consumes, but the FDA inspects less than one percent of that seafood specifically for fraud. Obviously this needs to change and we need to call upon our lawmakers to ensure full traceability for all seafood sold in the country. Oceana is hard at work behind the scenes to make this happen. In the meantime, if you don’t want to be duped by seafood fraud you can start by asking where and how your seafood was caught, be wary of fish that seems cheaper than it should and, when possible, buy fish whole.
Seafood is one of the healthiest sources of protein on the planet and should be a part of any healthy diet, but we need to know that what we’re buying is what the label says it is—for the good of our health, our wallets and our oceans.
Andy Sharpless is the CEO of Oceana
Pablo is a big boy. He slowed down for a while, but he’s back up to Super Typhoon (Cat 5) status. He hits the south of Philippines in the morning. The whole country is braced. Strongest typhoon in 22 years. Currently 260 km/hr.
Here’s hoping for the best for those in his path. Stay safe and dry Mindanao, Visayas, Palawan.
Because they spend so much time in remote waters, and don’t survive in captivity, great white sharks are deeply mysterious creatures. But over the last ten years, biologists have been able to track them using electronic tags which record their position and depth, and the ocean temperature.
On the face of it, that information can’t tell you what the sharks are actually doing. But Salvador Jorgensen of the Monterey Bay Aquarium in Monterey, California, and colleagues have developed a new statistical analysis that picks out patterns of behaviour from the tagging data.
It seems to confirm earlier suggestions that the sharks have a breeding ground in the east Pacific. What’s more, it suggests that the males go there to show off side-by-side in front of the choosy females – cattle-market style.
Nutrient-rich slurry from farms has been causing coral populations on Australia’s Great Barrier Reef to crash for 90 years.
The corals collapsed between the 1920s and 1950s, say John Pandolfi at the University of Queensland in Brisbane and his colleagues. The team took cores from three reefs and worked out when the corals died. Two had little coral left after the 1950s, while the third had been colonised since then by different types.
By the 1920s, European settlers were farming intensively near rivers flowing onto the reef, boosting agricultural run-off by up to a factor of 20. Events like cyclones kill coral, but the extra nutrients in the water help seaweed move in afterwards, preventing coral from regenerating, says Terry Done of the Australian Institute of Marine Science in Townsville, Queensland.
The reefs were already in decline again when monitoring began in the 1980s, says Joana Figueiredo of James Cook University, also in Townsville. Pandolfi’s work shows that it was pristine until the 1920s.
Journal reference: Proceedings of the Royal Society B, DOI: 10.1098/rspb.2012.2100
Devoted Deep Sea Squid Mama
Parental instincts aren’t exactly common place in the invertebrate world. Squid typically die after spawning, leaving orphaned squidlets to fend for themselves in the big bad ocean. But as in all of biology, there are exceptions.
Check out this incredible image of a mama squid tending to her (approx. 360) eggs — only the second species of brooding squid to be discovered, ever!
Man, the deep sea is cool. Cephalopods are also cool.
This paper was just published. Imagine how many more cool squid are down there.
Beluga whale ‘makes human-like sounds’
Researchers in the US have been shocked to discover a beluga whale whose vocalisations were remarkably close to human speech.
While dolphins have been taught to mimic the pattern and durations of sounds in human speech, no animal has spontaneously tried such mimicry.
But researchers heard a nine-year-old whale named NOC make sounds octaves below normal, in clipped bursts.
The researchers outline in Current Biology just how NOC did it.
But the first mystery was figuring out where the sound was coming from. The whales are known as “canaries of the sea” for their high-pitched chirps, and while a number of anecdotal reports of whales making human-like speech, none had ever been recorded.
When a diver at the National Marine Mammal Foundation in California surfaced saying, “Who told me to get out?” the researchers there knew they had another example on their hands.
Once they identified NOC as the culprit, they made the first-ever recordings of the behaviour.
They found that vocal bursts averaged about three per second, with pauses reminiscent of human speech. Analysis of the recordings showed that the frequencies within them were spread out into “harmonics” in a way very unlike whales’ normal vocalisations and more like those of humans.
They then rewarded NOC for the speech-like sounds to teach him to make them on command and fitted him with a pressure transducer within his nasal cavity, where sounds are produced, to monitor just what was going on.
They found that he was able to rapidly change the pressure within his nasal cavity to produce the sounds.
To amplify the comparatively low-frequency parts of the vocalisations, he over-inflated what is known at the vestibular sac in his blowhole - which normally acts to stop water entering the lungs.
In short, the mimicry was no easy task for NOC.
“Our observations suggest that the whale had to modify its vocal mechanics in order to make the speech-like sounds,” said Sam Ridgway, president of the National Marine Mammal Foundation and lead author on the paper.
“The sounds we heard were clearly an example of vocal learning by the white whale.”
Dear Cathay Pacific,
I applaud you for your decision to ban the transport of shark fin products on your carriers and subsidiary airline Dragon Air.
Anti-shark fin campaigners estimated that you flew 50% of the air cargo trade into Hong Kong each year, equating up to 650 tonnes of shark fins. You claimed it was less than this, but no matter how much it was, you’ve stopped. Thank you.
Whether it’s because of the petition that was signed in July, or your years of research into the matter, you’ve stopped. Thank you.
Your decision means that you’ve restricted the availability of shark fin products in Hong Kong and mainland China. It means you are part of many companies that are helping to turn the tide against the unsustainable shark fin industry. Once again, thank you.
Everyone (because saving sharks is saving ourselves).
Robot surfboard tracks great white sharks off the coast of California
What does this mean, apart from awesome? It means you can get a free iPhone app to follow these (up to 6m+) babies around.
Sharks in your pocket.
Way better than Polly Pocket.