From the BBC
20 August 2015 Last updated at 19:48 BST
Showing posts with label jellyfish. Show all posts
Showing posts with label jellyfish. Show all posts
Saturday, August 29, 2015
Jellyfish Trends
Map of population trends of native and invasive species of jellyfish Increase (high certainty) Increase (low certainty) Stable/variable Decrease No data
https://en.wikipedia.org/wiki/Jellyfish / From April 2012
Saturday, July 19, 2014
More Jellyfish Off the Coast of Maine
From the Portland Press Herald:
As jellyfish come in waves off Maine coast, questions follow - The early summer invasion appears to be heavier than normal this year, surprising some and distressing others.
Or, the June bloom could be a random explosion of a species that goes as fast as it comes.
Although they move without intent, drifting on currents, jellies – the term scientists tend to use for the gelatinous zooplankton these days, rather than jellyfish – are opportunists. They take advantage of holes in the system, competing with fish for the same tiny nutrients.
The waters off Maine have three types – moon jellies, comb jellies and lion’s mane jellies. Only the lion’s mane has a sting harmful to humans.
“It is frustrating to not be able to say anything other than speculative things about why,” she said.
That’s because no one in Maine has made a study of them. Trying to get a jelly expert on the phone is like playing a game of hot potato where you’re the potato, but all roads seem to lead to Andrew Pershing, chief scientific officer and ecosystem modeler at the Gulf of Maine Research Institute in Portland. Even he demurs.
But at least one researcher, Nick Record of the Bigelow Laboratory for Ocean Sciences in East Boothbay, has decided after two seasons of a noted increase in jellies that it is high time to start tracking the species in Maine. This summer he began building a library of the species spotted here and hopes to create predictive models that might tell us when to expect jelly blooms like the one that began this June.
“Then hopefully, a field program,” Record said. That’s all contingent on getting funding, because as he points out, although the public is more aware than ever about what is happening on the Maine coast – and ready to send an email or make a phone call to report it – there is less funding for such studies because of federal cutbacks in research.
“We have had jellyfish before,” he said. “But we haven’t had jellyfish where you look off the dock and all you see is jellyfish.”
“This year it was scary,” said Anne Murphy, whose family has owned a summer place in Brigham’s Cove since the late 1970s. She opted not to swim in the jelly-thickened water.
“I looked down in the water and I was like, ‘What is that?’ I have never seen so many,” Murphy said.
For weeks, Maine’s marine research centers have been flooded with questions about a seeming jellyfish invasion in local waters, primarily Casco Bay. They’ve ranged from the urgent – should I let my kids go in the water, or are they going to get stung? – to expressions of longer-term fears, namely, is this the result of global warming? Ocean acidification in the warming Gulf of Maine? Proof of a hypothesis that we’re headed for an ocean ecosystem clogged by jellies, creatures that cause many beachgoers to shudder in revulsion?
Researchers across the board say they just don’t know what the cause is. It could be climate change, including warmer waters. It could be a depletion of oxygen in coastal waters because of runoff from the land, or some response to overfishing.
Cathy Ramsdell, executive director of the Friends of Casco Bay, said her group has been getting questions about the creatures “everywhere we go this summer.”
“I am the person willing to talk about jellyfish, but it is an interesting state of affairs where I am what passes for an expert on jellyfish,” Pershing said. “I can’t think of anyone who studies them (in Maine) and we don’t really have good data on the distribution of jellyfish.”
“It’s hard talking to scientists because none of them want to commit and none of them want to be wrong,” said Dan Devereaux, marine warden for the town of Brunswick. He believes it’s all about elevated ocean temperatures....
Tuesday, November 05, 2013
"Jellyfish taking over oceans, experts warn"
(CNN) --
"Jellyfish and tourism are not happy bedfellows," says Dr. Lisa-Ann Gershwin, author of the recently published book, "Stung! On Jellyfish Blooms and the Future of the Ocean."
Gershwin says popular beach resorts around the world are seeing huge increases in jellyfish "bloom" activity, a result of overfishing and changing water temperatures.
"The French and Spanish Rivieras, Chesapeake Bay, the Great Barrier Reef, Hawaii ... some of the numbers are staggering," says the American scientist who's now based in Australia.
"In Hawaii there have been times that 800 or 1,000 people have been stung in a day. In Spain or Florida, it's not uncommon in recent years for a half a million people to be stung during an outbreak. These numbers are simply astonishing."
At the beginning of October, a large amount of jellyfish inhabiting a cooling-water intake at a Swedish nuclear plant caused operators to manually shut down production at its largest reactor.
In Ireland, a jellyfish bloom reportedly killed thousands of farmed salmon, according to the Irish Times.
This past summer, southern Europe experienced one of its worst jellyfish infestations ever. Experts there have been reporting a steady increase in the number of jellyfish in the Mediterranean Sea for years.
According to a report titled "Review of Jellyfish Blooms in the Mediterranean and Black Sea," written by Fernando Borea for the General Fisheries Commission for the Mediterranean and the United Nations, scientists are catching up to what travelers in the Med have been experiencing for years.
"In the last decade ... the media are reporting on an increasingly high number of gelatinous plankton blooms," reads the report. "The reason for these reports is that thousands of tourists are stung, fisheries are harmed and even impaired by jellyfish."
Although noting that significant jellyfish blooms "have been known since ancient times and are part of the normal functioning of the oceans," the report cites global warming and global overfishing (which removes jellyfish predators) as causes for exploding jellyfish populations in recent years.
The situation in the Mediterranean was dire enough to prompt Britain's foreign office to issue a warning to its citizens vacationing along Europe's southern coast to watch out for jellyfish.
There are more than 2,000 species of jellyfish swimming through the world's waters.
Most stings are completely harmless. Some will leave you in excruciating pain.
Then there are the killers.
Many of the world's deadliest jellyfish are box jellyfish, which refers to the species' cube-shaped meduae.
"There are several species of big box jellyfish that have caused many deaths -- these include chironex fleckeri in Australia, chironex quadrigatus in Japan and related species in Thailand, Papua New Guinea and Indonesia," says associate professor Jamie Seymour, a venom biologist at Australia's James Cook University.
Also known as the sea wasp and the northern Australian box jellyfish, the chironex fleckeri is possibly the worlds most venomous animal.
Its tentacles can reach lengths of up to three meters long, while its bell is about the size of a human head. It can be found throughout the tropical waters of the Indo-Pacific.
A close cousin and fellow contender for the "world's most venomous" cup is the Irukandji, which is the size of a thimble.
Good luck scanning the waters for that one before you leap in.
"How toxic they are is just phenomenally frightening and equally fascinating," says Gershwin.
"Just the lightest brush -- you don't even feel it -- and then, whammo, you're in more pain than you ever could have imagined, and you are struggling to breathe and you can't move your limbs and you can't stop vomiting and your blood pressure just keeps going up and up.
"It is really surprising how many places they occur around the world -- places you would never expect: Hawaii, Caribbean, Florida, Wales, New Caledonia, Thailand, Malaysia, Philippines, India ... as well as Australia."
Is any place safe?
"More and more, places around the world that are suffering from jellyfish problems with tourists are developing prediction systems so that tourists can know when it is safe," says Gershwin.
The irony, she says, is that tourists who avoid an area because of the known risk may alter their plans to hit a "safe" beach whose officials are merely less up front about the jellyfish situation, putting themselves more at risk.
A common misconception is that places such as Indonesia, Thailand, Malaysia and the Philippines are free of dangerous jellyfish.
"Jellyfish occur in all marine waters from pole to pole and at all depths," says Gershwin. "The life threatening ones are found from about 40 degrees north to 40 degrees south latitude.
"Australia is upfront about its jellyfish dangers, and also assertive in safety management, whereas other places have them, but may understand less about them or, in some cases, just don't want to say. I think tourists need to be very aware of local hazards and not expect to necessarily be provided with information."
Friday, November 30, 2012
"Can a Jellyfish Unlock the Secret of Immortality?"
From the New York Times By NATHANIEL RICH:
The "immortal jellyfish" can transform itself back into a polyp and begin life anew.
The "immortal jellyfish" can transform itself back into a polyp and begin life anew.
After more than 4,000 years — almost since the dawn of recorded time, when Utnapishtim told Gilgamesh that the secret to immortality lay in a coral found on the ocean floor — man finally discovered eternal life in 1988. He found it, in fact, on the ocean floor. The discovery was made unwittingly by Christian Sommer, a German marine-biology student in his early 20s. He was spending the summer in Rapallo, a small city on the Italian Riviera, where exactly one century earlier Friedrich Nietzsche conceived “Thus Spoke Zarathustra”: “Everything goes, everything comes back; eternally rolls the wheel of being. Everything dies, everything blossoms again. . . .”
Sommer was conducting research on hydrozoans, small invertebrates that, depending on their stage in the life cycle, resemble either a jellyfish or a soft coral. Every morning, Sommer went snorkeling in the turquoise water off the cliffs of Portofino. He scanned the ocean floor for hydrozoans, gathering them with plankton nets. Among the hundreds of organisms he collected was a tiny, relatively obscure species known to biologists as Turritopsis dohrnii. Today it is more commonly known as the immortal jellyfish.
Sommer kept his hydrozoans in petri dishes and observed their reproduction habits. After several days he noticed that his Turritopsis dohrnii was behaving in a very peculiar manner, for which he could hypothesize no earthly explanation. Plainly speaking, it refused to die. It appeared to age in reverse, growing younger and younger until it reached its earliest stage of development, at which point it began its life cycle anew.
Sommer was baffled by this development but didn’t immediately grasp its significance. (It was nearly a decade before the word “immortal” was first used to describe the species.) But several biologists in Genoa, fascinated by Sommer’s finding, continued to study the species, and in 1996 they published a paper called “Reversing the Life Cycle.” The scientists described how the species — at any stage of its development — could transform itself back to a polyp, the organism’s earliest stage of life, “thus escaping death and achieving potential immortality.” This finding appeared to debunk the most fundamental law of the natural world — you are born, and then you die.
One of the paper’s authors, Ferdinando Boero, likened the Turritopsis to a butterfly that, instead of dying, turns back into a caterpillar. Another metaphor is a chicken that transforms into an egg, which gives birth to another chicken. The anthropomorphic analogy is that of an old man who grows younger and younger until he is again a fetus. For this reason Turritopsis dohrnii is often referred to as the Benjamin Button jellyfish.
We now know, for instance, that the rejuvenation of Turritopsis dohrnii and some other members of the genus is caused by environmental stress or physical assault. We know that, during rejuvenation, it undergoes cellular transdifferentiation, an unusual process by which one type of cell is converted into another — a skin cell into a nerve cell, for instance. (The same process occurs in humanstem cells.) We also know that, in recent decades, the immortal jellyfish has rapidly spread throughout the world’s oceans in what Maria Pia Miglietta, a biology professor at Notre Dame, calls “a silent invasion.” The jellyfish has been “hitchhiking” on cargo ships that use seawater for ballast. Turritopsis has now been observed not only in the Mediterranean but also off the coasts of Panama, Spain, Florida and Japan. The jellyfish seems able to survive, and proliferate, in every ocean in the world. It is possible to imagine a distant future in which most other species of life are extinct but the ocean will consist overwhelmingly of immortal jellyfish, a great gelatin consciousness everlasting....
The genus, it turns out, is extraordinarily difficult to culture in a laboratory. It requires close attention and an enormous amount of repetitive, tedious labor; even then, it is under only certain favorable conditions, most of which are still unknown to biologists, that a Turritopsis will produce offspring.
In fact there is just one scientist who has been culturing Turritopsis polyps in his lab consistently. He works alone, without major financing or a staff, in a cramped office in Shirahama, a sleepy beach town in Wakayama Prefecture, Japan, four hours south of Kyoto. The scientist’s name is Shin Kubota, and he is, for the time being, our best chance for understanding this unique strand of biological immortality....
The world’s only captive population of immortal jellyfish lives in petri dishes arrayed haphazardly on several shelves of a small refrigerator in Kubota’s office. Like most hydrozoans, Turritopsis passes through two main stages of life, polyp and medusa. A polyp resembles a sprig of dill, with spindly stalks that branch and fork and terminate in buds. When these buds swell, they sprout not flowers but medusas. A medusa has a bell-shaped dome and dangling tentacles. Any layperson would identify it as a jellyfish, though it is not the kind you see at the beach. Those belong to a different taxonomic group, Scyphozoa, and tend to spend most of their lives as jellyfish; hydrozoans have briefer medusa phases. An adult medusa produces eggs or sperm, which combine to create larvae that form new polyps. In other hydroid species, the medusa dies after it spawns. A Turritopsis medusa, however, sinks to the bottom of the ocean floor, where its body folds in on itself — assuming the jellyfish equivalent of the fetal position. The bell reabsorbs the tentacles, and then it degenerates further until it becomes a gelatinous blob. Over the course of several days, this blob forms an outer shell. Next it shoots out stolons, which resemble roots. The stolons lengthen and become a polyp. The new polyp produces new medusas, and the process begins again.
Kubota estimates that his menagerie contains at least 100 specimens, about 3 to a petri dish. “They are very tiny,” Kubota, the proud papa, said. “Very cute.” It is cute, the immortal jellyfish. An adult medusa is about the size of a trimmed pinkie fingernail. It trails scores of hairlike tentacles. Medusas found in cooler waters have a bright scarlet bell, but more commonly the medusa is translucent white, its contours so fine that under a microscope it looks like a line drawing. It spends most of its time floating languidly in the water. It’s in no rush...
“The mystery of life is not concealed in the higher animals,” Kubota told me. “It is concealed in the root. And at the root of the Tree of Life is the jellyfish.” (more)
Tuesday, July 31, 2012
"Rare jellyfish appears in San Diego Bay"
From LA Times Blogs:
A rare species of jellyfish, distinguishable by its black color and long tentacles, is being spotted along a stretch of San Diego Bay popular with boaters.
A rare species of jellyfish, distinguishable by its black color and long tentacles, is being spotted along a stretch of San Diego Bay popular with boaters.
With the formal name of Chrysaora achlyos, the so-called "black jellyfish" range from Monterey Bay to the tip of Baja California and seem to be making increasing appearances in San Diego-area waters, perhaps because the water is getting warmer.
This summer, they have been spotted near Shelter Island.
Stepping on the jellyfish, or otherwise coming into contact with one, can be a painful experience. The creatures have nettles that sting and immobilize their prey. Even a dead jellyfish carries a sting -- not enough to kill a human, but enough to be unpleasant.
The jellyfish's body can measure 3 feet in diameter, and the tentacles can be 25 feet or more in length.
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The black jellyfish (which can weigh 50 pounds) seem to like the Coronado beaches:
Tuesday, April 17, 2012
Jellyfish blooms creating oceans of slime
We here at Universal Jellyfish have been on top of this for awhile. If people decide to get serious about eating them - that would probably take care of it.
Here is a BBC article with updates:
In the last decade enormous plagues of jellyfish have been taking over the seas. And it is our fault.
As I rose to a couple of metres below the surface, I saw the problem too late: the shallow water was carpeted with mauve stinger jellyfish (Pelagia noctiluca). There was no avoiding it, reaching the surface meant I had to swim through the flames of stingers....
Locals told me the carpet of jellyfish, known as a bloom, was not an isolated case. My dive instructor said he had seen massive blooms off the coast of Gozo every year since 2000. But never before then.
In fact, huge annual jellyfish blooms have been cropping up not just across the Mediterranean, but also the Black Sea, the Gulf of Mexico, and the Yellow and Japan Seas. Is this a bizarre blip in the continually changing balance of oceanic life, or the beginnings of a new state change in marine diversity?Or in other words: in the Anthropocene, will the seas be filled with slime?If they are, we face some serious problems.
Last year alone, nuclear power plants in Scotland, Japan, Israel and Florida, and also a desalination plant in Israel, were forced to shutdown because jellyfish were clogging the water inlets. The entire Irish salmon industry was wiped out in 2007 after a plague of billions of mauve stingers – covering an area of 10 sq miles (26 sq km) and 35ft (11m) deep – attacked the fish cages. Two years later, a fish farm in Tunisia lost a year's production of sea bream and sea bass after jellyfish invasions.
Perhaps the most extraordinary blooms have been those occurring in waters off Japan. There, refrigerator-sized gelatinous monsters called Nomuras, weighing 485lb (220 kg) and measuring 6.5ft (2m) in diameter, have swarmed the Japan Sea annually since 2002, clogging fishing nets, overturning trawlers and devastating coastal livelihoods. These assaults have cost the Japanese fisheries industry billions of yen in losses.
Marine ecologists are warning of worse to come, and pointing the tentacle of blame at us. Some researchers fear that human changes to the marine environment may be leading to a tipping point in which jellyfish will rule the oceans, much as they did hundreds of millions of years ago in pre-Cambrian times. In 2009, Australian marine scientist Anthony Richardson and his colleagues published a research paper entitled The jellyfish joyride, in which they warn that if we do not act to curb current blooms, we will experience runaway populations that will cause open oceanic ecosystems to flip from ones dominated by fish biodiversity to ones dominated by jellyfish.
The problem is that no one really knows what causes the blooms. Some believe that population explosions result from overfishing of their dining competitors and predators, which include more than 100 species of fish, and animals such as turtles. However, other researchers point out that overfishing also hits jellyfish by reducing their food availability.Either way, what is clear is that jellyfish are simply better prepared than other marine life for many of the ways humans are changing the ocean environment, such as warmer temperatures, salinity changes, ocean acidification and pollution. In this sense, humans might be jellyfishes’ best friend.
For instance, pollution can cause algal blooms that reduce the water's oxygen content. This hits muscular swimmers like fish hard, but jellyfish can cope far better with these conditions.
Warmer water encourages jellyfish reproduction, and they can also better tolerate population crashes because their reproductive strategies are complex and adaptable. Some species of jelly can clone themselves, whereas others reproduce sexually but also have a polyp stage – like corals, with which they are related – that allows large populations of immature individuals to multiply while waiting for the right conditions to mature into adulthood. In these ways, they can withstand impacts that devastate other marine species.
Even the coastal infrastructure we build seems to be working to their advantage. Rob Condon, a marine scientist at Dauphin Island Sea Lab in Alabama, says that the pontoons, piers and even drilling platforms help provide anchors for jellyfish polyps, encouraging local population explosions....
Gathering data on jellyfish, though, is notoriously difficult. Although 70% of the planet is covered by ocean, we really only have a hazy idea about most of the life outside of coastal or estuarine zones. Jellyfish, which inhabit open oceans and deep waters, are still an enigma in many ways. Monitoring individuals and blooms cannot be done by satellite because they are so transparent, have very low biomass, and often occupy waters below the optical depth for satellite penetration. Even finding polyps and larvae in sea grass is tricky. So, despite JEDI's efforts, no one can say for sure whether blooms are increasing or not....
Perhaps one solution is to sustainably exploit their abundance. Jellyfish do have their uses: in collagen preparations (to treat rheumatoid arthritis, for example), they are popular attractions in aquaria, and their fluorescent proteins have been instrumental in biomedical discoveries.
And, of course, they are a source of food. In Japan and other parts of Asia, jellyfish are dried and chopped into noodle-like strips to be added to soups, for example. Some entrepreneurial Japanese are even making vanilla-and-jellyfish ice cream. Jellyfish are 80% protein and very low in fat, although the high sodium content probably outweighs their health benefits.
Monday, February 20, 2012
"Warmer Planet Could Be Dominated by Mosquitoes, Tics, Rodents and Jellyfish"
Of course we at Universal Jellyfish knew about the jellyfish, ticks, & mosquitoes - rodents is a new one...and swans...(though I doubt that global warming will be good for any mammals in the long run).
Article in Scientific American today:
Imagine a planet where jellyfish rule the seas, giant rodents roam the mountains and swarms of insects blur everything in sight. It may sound far-fetched, but enough global warming is likely to change the distribution of wildlife on Earth. While species that are under threat, such as the polar bear, seem to get all the attention, others are beginning to thrive like never before.
In the past three months, new studies have been published about killer whales, wandering albatross and trumpeter swans—all of which appear to be benefiting from climate change.
Melting ice is turning the Arctic Sea into a giant buffet for killer whales. They have been arriving in growing numbers to feed on belugas, seals and narwhals, according to a recent study by scientists from the University of Manitoba. Warmer temperatures make it easier for the whales to hunt because their prey is less likely to climb onto sea ice or hide below it to escape.
At the opposite end of the world, in Antarctica's Southern Ocean, changing winds have been helping the wandering albatross find food faster. Researchers say global warming has produced stronger air currents that allow the birds to spend less time away from their nests, increasing the odds that their chicks will survive.
"The duration of foraging trips has decreased, breeding success has improved and birds have increased in mass by more than 1 kilogram," wrote the study's authors, who called their findings "positive consequences of climate change."
In Arctic areas, global warming is happening at roughly twice the average speed, which has allowed Alaska's trumpeter swans to expand their breeding grounds northward into regions that were previously too cold, according to a study published in Wildlife Biology in December.
....White-tailed deer in the northern United States are already showing a population boom thanks to this year's lack of snowfall, which has made it easier for the animals to find food, said Curtis. He also believes a warmer spring could benefit snakes and salamanders, giving them more time to grow and add to their fat reserves.
...Jellyfish populations are also suspected to be swelling because of climate change. In recent years, the creatures have been clogging the nets of fishermen, stinging record numbers of beachgoers and blocking the water intake lines of power plants in at least three countries. Some scientists are linking the phenomenon to warmer waters and ocean acidification caused by high levels of carbon dioxide in the atmosphere. Studies have found that today's oceans are 30 percent more acidic than in the 18th century, when the Industrial Revolution began.
...Certain species of insects, like mosquitoes, ticks and invasive beetles, are also expected to benefit from warmer temperatures. In fact, a 2003 study published by the Ecological Society of America concluded that "all aspects of insect outbreak behavior will intensify as the climate warms."
...Future levels of carbon dioxide may help beetles, as well, according to researchers from the University of Illinois, Urbana-Champaign, who found that Japanese beetles lived longer and laid more eggs after eating leaves that were grown in an environment with additional carbon dioxide.
..."What we really don't know is what the long-term consequences of climate change are," explained Curtis. "There will definitely be winners and losers, and it's hard to predict what some of those will be." He said animals that can migrate—like whales and birds—are more likely to adapt, while species bound to a particular environment, or food source, will face greater challenges.
Even creatures that appear to be benefiting today may not be so lucky in the future. Scientists predict the winds that are helping the wandering albatross will become increasingly violent by the end of the century, threatening the birds' survival. And Colorado's marmots don't easily adapt to heat, so rising temperatures may soon put them—and the plants they eat—at risk.
"It's hard to say if swans will even benefit long-term," said Schmidt, who explained that the ponds they live in may already be drying up. "If those sorts of things are occurring, it might be a zero-sum game. Or it might be negative."
Wednesday, October 19, 2011
"Jellyfish image wins wildlife prize" UK
An image of a jellyfish captured off a small uninhabited Scottish island has scooped the top £5,000 prize in this year's British Wildlife Photography Awards.
The photograph taken by Richard Shucksmith from Shetland was snapped at Sula Sgeir, which means Gannet Rock, a remote island 41 miles north of Lewis that is home to a wide array of marine life.
Greg Armfield, photography and film manager at wildlife charity WWF, described the shot as "fantastic".
He said it was "a truly beautiful shot of a jellyfish that perfectly captures its iridescent colours and magical qualities; all the more remarkable that it exists in UK waters."
The competition, now in its third year, awards a top prize to the overall winner and also £1,000 of prizes from Canon for 10 categories, ranging from animal portraits and behaviour to landscapes, urban wildlife and the British seasons.
Monday, July 11, 2011
Regarding Mackerel & Jellyfish
By George Monbiot:
Last year I began to wonder, this year doubt is seeping away, to be replaced with a rising fear. Could it really have happened? Could the fishing industry have achieved the remarkable feat of destroying the last great stock?
Until 2010, mackerel were the one reliable catch in Cardigan Bay in west Wales. Though I took to the water dozens of times, there wasn't a day in 2008 or 2009 when I failed to take 10 or more. Once every three or four trips I would hit a major shoal, and bring in 100 or 200 fish: enough, across the season, to fill the freezer and supply much of our protein for the year. Those were thrilling moments: pulling up strings of fish amid whirling flocks of shearwaters, gannets pluming into the water beside my kayak, dolphins breaching and blowing. It was, or so it seemed, the most sustainable of all the easy means of harvesting animal protein.
Even those days were nothing by comparison to what the older residents remembered: weeks on end when the sea was so thick with fish that you could fill a bucket with mackerel just by picking them off the sand, as they flung themselves through and beyond the breaking waves while pursuing their prey.
Last year it all changed. From the end of May to the end of October I scoured the bay, on one occasion paddling six or seven miles from land – the furthest I've ever been – to try to find the fish. With the exception of a day on which I caught 20, I brought them back in ones or twos, if at all. There were many days on which I caught nothing at all.
There were as many explanations as there were fishermen: the dolphins had driven them away, the north-westerlies had broken up the shoals, a monstrous fishmeal ship was stationed in the Irish Sea, hoovering up 500 tonnes a day with a fiendish new vacuum device. (Despite a wealth of detail on this story I soon discovered that no such ship existed. But that's fishermen for you).
I spoke to a number of fisheries officials and scientists, and was shocked to discover that not only did they have no explanation, they had no data either.
So I hoped for the best – that the dearth could be explained by a fluctuation of weather or ecology. When the fish failed to arrive at the end of May I told myself they must be on their way. They had, after all, been showing off the south-west of England – it could be only a matter of time. I held off until last weekend...
Far below me I could see the luminous feathers I used as bait tripping over the seabed.
But I could also see something else. Jellyfish. Unimaginable numbers of them. Not the transparent cocktail umbrellas I was used to, but solid, white rubbery creatures the size of footballs. They roiled in the surface or loomed, vast and pale, in the depths. There was scarcely a cubic metre of water without one.
Apart from that – nothing. It wasn't until I reached a buoy three miles from the shore that I felt the urgent tap of a fish, and brought up a single, juvenile mackerel. Otherwise, though I paddled to all the likely spots, I detected nothing but the jellyfish rubbing against the line.
Is this the moment? Have I just witnessed the beginning of the end of vertebrate ecology here? If so, the shift might not be confined to Cardigan Bay. In a perfect conjunction of two of my recent interests, last week a monstrous swarm of jellyfish succeeded where Greenpeace has failed, and shut down both reactors at the Torness nuclear power station in Scotland.
The Israeli branch of Jellyfish Action pulled off a similar feat at the nuclear power station in Hadera this week.
A combination of overfishing and ocean acidification (caused by rising concentrations of carbon dioxide in the atmosphere) has created the perfect conditions for this shift from a system dominated by fish to a system dominated by jellyfish....
Last year I began to wonder, this year doubt is seeping away, to be replaced with a rising fear. Could it really have happened? Could the fishing industry have achieved the remarkable feat of destroying the last great stock?
Until 2010, mackerel were the one reliable catch in Cardigan Bay in west Wales. Though I took to the water dozens of times, there wasn't a day in 2008 or 2009 when I failed to take 10 or more. Once every three or four trips I would hit a major shoal, and bring in 100 or 200 fish: enough, across the season, to fill the freezer and supply much of our protein for the year. Those were thrilling moments: pulling up strings of fish amid whirling flocks of shearwaters, gannets pluming into the water beside my kayak, dolphins breaching and blowing. It was, or so it seemed, the most sustainable of all the easy means of harvesting animal protein.
Even those days were nothing by comparison to what the older residents remembered: weeks on end when the sea was so thick with fish that you could fill a bucket with mackerel just by picking them off the sand, as they flung themselves through and beyond the breaking waves while pursuing their prey.
Last year it all changed. From the end of May to the end of October I scoured the bay, on one occasion paddling six or seven miles from land – the furthest I've ever been – to try to find the fish. With the exception of a day on which I caught 20, I brought them back in ones or twos, if at all. There were many days on which I caught nothing at all.
There were as many explanations as there were fishermen: the dolphins had driven them away, the north-westerlies had broken up the shoals, a monstrous fishmeal ship was stationed in the Irish Sea, hoovering up 500 tonnes a day with a fiendish new vacuum device. (Despite a wealth of detail on this story I soon discovered that no such ship existed. But that's fishermen for you).
I spoke to a number of fisheries officials and scientists, and was shocked to discover that not only did they have no explanation, they had no data either.
So I hoped for the best – that the dearth could be explained by a fluctuation of weather or ecology. When the fish failed to arrive at the end of May I told myself they must be on their way. They had, after all, been showing off the south-west of England – it could be only a matter of time. I held off until last weekend...
Far below me I could see the luminous feathers I used as bait tripping over the seabed.
But I could also see something else. Jellyfish. Unimaginable numbers of them. Not the transparent cocktail umbrellas I was used to, but solid, white rubbery creatures the size of footballs. They roiled in the surface or loomed, vast and pale, in the depths. There was scarcely a cubic metre of water without one.
Apart from that – nothing. It wasn't until I reached a buoy three miles from the shore that I felt the urgent tap of a fish, and brought up a single, juvenile mackerel. Otherwise, though I paddled to all the likely spots, I detected nothing but the jellyfish rubbing against the line.
Is this the moment? Have I just witnessed the beginning of the end of vertebrate ecology here? If so, the shift might not be confined to Cardigan Bay. In a perfect conjunction of two of my recent interests, last week a monstrous swarm of jellyfish succeeded where Greenpeace has failed, and shut down both reactors at the Torness nuclear power station in Scotland.
The Israeli branch of Jellyfish Action pulled off a similar feat at the nuclear power station in Hadera this week.
A combination of overfishing and ocean acidification (caused by rising concentrations of carbon dioxide in the atmosphere) has created the perfect conditions for this shift from a system dominated by fish to a system dominated by jellyfish....
Friday, July 01, 2011
“Jellyfish” Ensemble"
Alexander McQueen (British, 1969–2010)
“Jellyfish” Ensemble
Plato’s Atlantis, spring/summer 2010
Dress, leggings, and “Armadillo” boots embroidered with iridescent enamel paillettes
In McQueen’s Words:
“[This collection predicted a future in which] the ice cap would melt . . . the waters would rise and . . . life on earth would have to evolve in order to live beneath the sea once more or perish. Humanity [would] go back to the place from whence it came.”
From the Metropolitan Museum of Art Blog
Thursday, June 09, 2011
"Changing Jellyfish Season Could Alter Chesapeake Bay Food Chain"
From - ClimateCentral.org
By Alyson Kenward
First came hundreds of reports of jellyfish washing ashore in central Florida over the Memorial Day weekend. Since then, people have been spotting blooms of the gelatinous drifters off the coasts Connecticut, Virginia, and South Carolina, all earlier in the summer than expected.
The early appearance of jellyfish along the East Coast is more than just a nuisance for beachgoers. According to scientists, it’s a sign that coastal waters are warmer than usual for time of year, and recent studies suggest the early jellyfish blooms could upset the marine ecosystem in coastal areas, like Maryland's Chesapeake Bay.
“The key thing with jellies is that they do everything so much faster than everything else, they grow and reproduce and are voracious predators, that other animals like fish can’t keep up,” says ecologist Rob Condon from the Dauphin Island Sea Lab in Alabama.
For several years, Condon and colleagues from the Sea Lab and the Virginia Institute of Marine Science (VIMS) have been studying jellyfish that live in the York River, a southern tributary of Chesapeake Bay. They’ve discovered that rapidly-growing blooms of jellyfish are feeding on some of the most nutritious parts of the food web, including small crustaceans, and are converting them into products that sustain bacteria that leave little valuable energy supplies for fish and other sea life.
Condon says the jellyfish are making a similar source of energy-rich material that bacteria feast upon, but that strips the nutritional value out of the river’s food web.
“Ultimately, there is less food for the fish, because the jellyfish are eating it all,” he says. And because not too many animals (including us humans) eat jellyfish, it doesn't seem as though the food energy going into the jellies is moving up the food chain. This week, Condon and his colleagues published a study in the Proceedings of the National Academy of Sciences, detailing how jellyfish blooms reduce diversity in the marine food chain....
According to Condon, if these warm waters continue to arrive in the earlier and earlier in the springtime, the effects could be felt throughout Chesapeake Bay. "Jellyfish are an important indicator of the health of a marine ecosystem," he says. "If the jellyfish blooms come earlier, there will be big consequences for fish production in the Bay."
_______________
I think we are going to have to learn to like eating jellyfish. I think it can be done.
By Alyson Kenward
First came hundreds of reports of jellyfish washing ashore in central Florida over the Memorial Day weekend. Since then, people have been spotting blooms of the gelatinous drifters off the coasts Connecticut, Virginia, and South Carolina, all earlier in the summer than expected.
The early appearance of jellyfish along the East Coast is more than just a nuisance for beachgoers. According to scientists, it’s a sign that coastal waters are warmer than usual for time of year, and recent studies suggest the early jellyfish blooms could upset the marine ecosystem in coastal areas, like Maryland's Chesapeake Bay.
“The key thing with jellies is that they do everything so much faster than everything else, they grow and reproduce and are voracious predators, that other animals like fish can’t keep up,” says ecologist Rob Condon from the Dauphin Island Sea Lab in Alabama.
For several years, Condon and colleagues from the Sea Lab and the Virginia Institute of Marine Science (VIMS) have been studying jellyfish that live in the York River, a southern tributary of Chesapeake Bay. They’ve discovered that rapidly-growing blooms of jellyfish are feeding on some of the most nutritious parts of the food web, including small crustaceans, and are converting them into products that sustain bacteria that leave little valuable energy supplies for fish and other sea life.
Condon says the jellyfish are making a similar source of energy-rich material that bacteria feast upon, but that strips the nutritional value out of the river’s food web.
“Ultimately, there is less food for the fish, because the jellyfish are eating it all,” he says. And because not too many animals (including us humans) eat jellyfish, it doesn't seem as though the food energy going into the jellies is moving up the food chain. This week, Condon and his colleagues published a study in the Proceedings of the National Academy of Sciences, detailing how jellyfish blooms reduce diversity in the marine food chain....
According to Condon, if these warm waters continue to arrive in the earlier and earlier in the springtime, the effects could be felt throughout Chesapeake Bay. "Jellyfish are an important indicator of the health of a marine ecosystem," he says. "If the jellyfish blooms come earlier, there will be big consequences for fish production in the Bay."
_______________
I think we are going to have to learn to like eating jellyfish. I think it can be done.
Thursday, April 28, 2011
Jellyfish Dress
White grocery bags, green dry cleaner bags, and blue newspaper bags that may have wound up polluting the ocean have now been crafted into an aquatic-themed gown.
Photo by: Courtesy of RecycleRunway.com
Seen on Shine.yahoo
Friday, January 21, 2011
Monday, August 23, 2010
Tybee sets a jellyfish sting record
From Savannahnow.com:
Mix throngs of beachgoers with throngs of jellyfish and what do you get?
Stings.
In fact, Tybee lifeguards have treated more than 10,000 jellyfish stings this season, said Lt. Hunter Robinson of Tybee Island Ocean Rescue.
In part, it's a record year for stings because there have been more potential victims. Tybee has seen healthy numbers of tourists, some who diverted to Georgia to avoid the threat of the Gulf oil spill.
To see what beach-goers have to say about the increase in jellyfish stings this summer, click play in the video box to the left.
The jellyfish have been there to greet those extra tourists in waves, both literally and figuratively. An unusually high population of lion's mane jellyfish plagued Tybee's surf in the spring and early summer.
That species prefers cooler water, so a later than normal warm-up last spring after a cold winter contributed to them overstaying their welcome at Tybee, said Beth Palmer, an educator at the Tybee Island Marine Science Center...
There's good evidence that jellyfish populations are increasing worldwide, said Dick Lee, professor emeritus at Skidaway Institute of Oceanography.
"Some areas that never had them before have them, and ones that had them before have more," he said.
Jellyfish research
Palmer, who's spearheaded a program she believes is the first in Georgia to collect data on jellyfish abundance, has been recording the number of jellies that wash up on a stretch of Tybee's beach.
Even these dead ones can hurt you, she cautioned, because their stingers are released with physical or chemical contact, not by the animal's control.
Jellies are poor swimmers dependent on the winds and currents to transport them. It's tough to know when they've peaked, Robinson said.
Lifeguards treated 400 stings on a recent Saturday, after seeing far fewer stings on the preceding days.
Still, it was about this time last year that Ocean Rescue recorded a sharp decline in stings. Robinson expects the worst is over.
Earlier this summer, Palmer was strolling through a tide pool when a slight current steered a jellyfish into her foot. She got her first-ever sting, one that kept her in pain for about 10 minutes.
But this self-described jelly-loving biologist hasn't turned on them.
"I think they're really pretty and really neat," she said.
Sting data
Number of jellyfish stings Tybee Island Ocean Rescue treated annually:
2006.........................1,370
2007..........................5,349
2008.........................1,933
2009.........................7,585
2010 (to date)............10,792
Mix throngs of beachgoers with throngs of jellyfish and what do you get?
Stings.
In fact, Tybee lifeguards have treated more than 10,000 jellyfish stings this season, said Lt. Hunter Robinson of Tybee Island Ocean Rescue.
In part, it's a record year for stings because there have been more potential victims. Tybee has seen healthy numbers of tourists, some who diverted to Georgia to avoid the threat of the Gulf oil spill.
To see what beach-goers have to say about the increase in jellyfish stings this summer, click play in the video box to the left.
The jellyfish have been there to greet those extra tourists in waves, both literally and figuratively. An unusually high population of lion's mane jellyfish plagued Tybee's surf in the spring and early summer.
That species prefers cooler water, so a later than normal warm-up last spring after a cold winter contributed to them overstaying their welcome at Tybee, said Beth Palmer, an educator at the Tybee Island Marine Science Center...
There's good evidence that jellyfish populations are increasing worldwide, said Dick Lee, professor emeritus at Skidaway Institute of Oceanography.
"Some areas that never had them before have them, and ones that had them before have more," he said.
Jellyfish research
Palmer, who's spearheaded a program she believes is the first in Georgia to collect data on jellyfish abundance, has been recording the number of jellies that wash up on a stretch of Tybee's beach.
Even these dead ones can hurt you, she cautioned, because their stingers are released with physical or chemical contact, not by the animal's control.
Jellies are poor swimmers dependent on the winds and currents to transport them. It's tough to know when they've peaked, Robinson said.
Lifeguards treated 400 stings on a recent Saturday, after seeing far fewer stings on the preceding days.
Still, it was about this time last year that Ocean Rescue recorded a sharp decline in stings. Robinson expects the worst is over.
Earlier this summer, Palmer was strolling through a tide pool when a slight current steered a jellyfish into her foot. She got her first-ever sting, one that kept her in pain for about 10 minutes.
But this self-described jelly-loving biologist hasn't turned on them.
"I think they're really pretty and really neat," she said.
Sting data
Number of jellyfish stings Tybee Island Ocean Rescue treated annually:
2006.........................1,370
2007..........................5,349
2008.........................1,933
2009.........................7,585
2010 (to date)............10,792
Tuesday, August 03, 2010
Lion's Mane Jellyfish around Long Island Sound
I went kayaking near Hammonasset Beach State Park in Connecticut at the end of June. My son and I saw quite a few reddish jellyfish which, as it turns out, are known as Lion's Mane Jellyfih.
This has apparently been a good year for the jellies. The Lion's Mane are food for the Leviathan Leatherback sea turtles.
Here are some excerpts from a New York Times article from July 22:
...[J]ellyfish have always been a blobbish summer menace to swimmers, fishermen and little children’s curious fingers.
But this year they have been even more of an annoyance than usual, arriving early and perplexing fishermen and beachgoers from Toms River, N.J., to Long Island and beyond. Biologists have several theories about why the jellyfish, particularly one breed, the lion’s mane, have turned out about a month before they are usually seen here.
Kenneth W. Able, director of the Rutgers University Marine Field Station in Tuckerton, N.J., said the early arrival could have something to do with recent winds from the south that blew away the sea’s warmer surface water, allowing an upwelling of cold water, which the lion’s mane loves.
Edward Enos, the superintendent of the Aquatic Resources Division for the Marine Biological Laboratory in Woods Hole, Mass., said conditions may have been perfect for an unusual number of baby jellyfish, called polyps, to survive.
“It’s nature,” Mr. Enos said. “It’s like some years you have beautiful, big blooms of dandelions in your yard, and sometimes not.”
On Monday, a steady stream of jellyfish undulated in the olive-colored water of the Hudson River between 79th and 98th Streets, where the swimmers had encountered them the day before. Their centers shifting up and down with the light tide, they were about six inches in diameter and looked like large floating paper cupcake wrappers stained in the center with red icing.
Splayed on a hard surface outside the water, they spread out into a gooey reddish-, orange-, olive- and cream-colored circle, some nearly a foot wide....
Jim Gilmore, director of marine resources for the State Department of Environmental Conservation, said that last Friday he started receiving calls about jellyfish. On Monday, he got a lot. Most years he doesn’t get jellyfish reports until August, he said.
John Lipscomb, a patrol boat operator for the Hudson Riverkeeper, an environmental group, said he saw a lion’s mane in the Harlem River for the first time last Monday. It was floating in a slew of garbage in the river.
“I looked over and in this massive soup of trash and debris was this beautiful pulsating jellyfish,” he said.
John Waldman, a professor of biology at Queens College, said that jellyfish may have moved upriver because of a lack of rain this year, which has pushed the salt water further upstream.
About a week ago, while boating with her mother on the Navesink River in New Jersey, 11-year-old Marissa Leli had her first encounter of the summer with a lion’s mane.
“It was all red, and the tentacles looked kind of scary,” said Marissa, who lives in Rumson, N.J., with her mother, Cindy Leli, 37. On Saturday, they were enjoying the ocean waves in Sea Bright, N.J., although they were on guard for jellyfish...
Mr. Grant, of the Sandy Hook Ocean Institute, said he first noticed them in April when young jellyfish the size of golf balls were turning up in fishing nets.
“This is a banner year if you like the look of jellyfish,” he said on Saturday afternoon after having netted a specimen, six inches in diameter, in the Atlantic Highlands Municipal Marina...
The lion’s mane, which can grow to eight feet in diameter and sport tentacles more than 100 feet long in arctic regions, usually does not exceed a foot in diameter in its southernmost range, Mr. Grant said. But the larger the jellyfish, the more painful the sting.
Bill Mack, 70, chief of beach operations and water safety in Sea Bright, said lifeguards were equipped with spray bottles of vinegar, which neutralizes the jellyfish’s venom.
“We spray it on people and they go away happy,” he said...
This has apparently been a good year for the jellies. The Lion's Mane are food for the Leviathan Leatherback sea turtles.
Here are some excerpts from a New York Times article from July 22:
...[J]ellyfish have always been a blobbish summer menace to swimmers, fishermen and little children’s curious fingers.
But this year they have been even more of an annoyance than usual, arriving early and perplexing fishermen and beachgoers from Toms River, N.J., to Long Island and beyond. Biologists have several theories about why the jellyfish, particularly one breed, the lion’s mane, have turned out about a month before they are usually seen here.
Kenneth W. Able, director of the Rutgers University Marine Field Station in Tuckerton, N.J., said the early arrival could have something to do with recent winds from the south that blew away the sea’s warmer surface water, allowing an upwelling of cold water, which the lion’s mane loves.
Edward Enos, the superintendent of the Aquatic Resources Division for the Marine Biological Laboratory in Woods Hole, Mass., said conditions may have been perfect for an unusual number of baby jellyfish, called polyps, to survive.
“It’s nature,” Mr. Enos said. “It’s like some years you have beautiful, big blooms of dandelions in your yard, and sometimes not.”
On Monday, a steady stream of jellyfish undulated in the olive-colored water of the Hudson River between 79th and 98th Streets, where the swimmers had encountered them the day before. Their centers shifting up and down with the light tide, they were about six inches in diameter and looked like large floating paper cupcake wrappers stained in the center with red icing.
Splayed on a hard surface outside the water, they spread out into a gooey reddish-, orange-, olive- and cream-colored circle, some nearly a foot wide....
Jim Gilmore, director of marine resources for the State Department of Environmental Conservation, said that last Friday he started receiving calls about jellyfish. On Monday, he got a lot. Most years he doesn’t get jellyfish reports until August, he said.
John Lipscomb, a patrol boat operator for the Hudson Riverkeeper, an environmental group, said he saw a lion’s mane in the Harlem River for the first time last Monday. It was floating in a slew of garbage in the river.
“I looked over and in this massive soup of trash and debris was this beautiful pulsating jellyfish,” he said.
John Waldman, a professor of biology at Queens College, said that jellyfish may have moved upriver because of a lack of rain this year, which has pushed the salt water further upstream.
About a week ago, while boating with her mother on the Navesink River in New Jersey, 11-year-old Marissa Leli had her first encounter of the summer with a lion’s mane.
“It was all red, and the tentacles looked kind of scary,” said Marissa, who lives in Rumson, N.J., with her mother, Cindy Leli, 37. On Saturday, they were enjoying the ocean waves in Sea Bright, N.J., although they were on guard for jellyfish...
Mr. Grant, of the Sandy Hook Ocean Institute, said he first noticed them in April when young jellyfish the size of golf balls were turning up in fishing nets.
“This is a banner year if you like the look of jellyfish,” he said on Saturday afternoon after having netted a specimen, six inches in diameter, in the Atlantic Highlands Municipal Marina...
The lion’s mane, which can grow to eight feet in diameter and sport tentacles more than 100 feet long in arctic regions, usually does not exceed a foot in diameter in its southernmost range, Mr. Grant said. But the larger the jellyfish, the more painful the sting.
Bill Mack, 70, chief of beach operations and water safety in Sea Bright, said lifeguards were equipped with spray bottles of vinegar, which neutralizes the jellyfish’s venom.
“We spray it on people and they go away happy,” he said...
Mauve Jellyfish invasion closes beaches across Spain
From the Telegraph.co.uk:
Several beaches on the Costa Blanca north of Alicante were closed to bathers after swarms of the Mauve Stinger jellyfish plagued the beaches of the Mediterranean.
The tentacles of the bright purple creatures, which emit a yellow glow at night, deliver mild stings but can cause severe allergic reactions in some people even leading to heart failure.
The Red Cross treated 50 people for stings in just half an hour last Thursday on a beach in Denia, a resort on Spain's eastern Mediterranean coast and fear numbers may reach that of 2008, when a record 4,000 people were treated for stings in Denia alone.
It is one of the most popular resorts on the Costa Blanca, a region which attracts an estimated two million foreign tourists each year – 40 per cent of them from Britain.
Spain's Environment Ministry has sent boats out to patrol the coastline on the lookout for dangerous clusters of the invertebrates drifting to shore.
Once spotted, red flags will be raised to warn swimmers to stay out of the water.
Over the last several years there has been a huge rise in numbers due to the effects of global warming and overfishing of their natural predators and each summer tens of thousands of holidaymakers are forced to seek treatment for minor stings.
Marine experts have this year also detected a rise in the number of the Carybdea marsupialis, known as box jellyfish, to the Costa Blanca...
Spain's Ministry of Environment said in a statement: "The exact reasons to explain jellyfish blooms are currently under research. They seem to be increasing in recent years and the most likely causes suggested are the decline of natural predators such as turtle and tuna; changes in climatic factors such as rainfall or global temperature; hydrographic peculiarities of the area, as well as pollution from land based sources."
Monday, July 12, 2010
"Giant jelly fish seen in the Adriatic"
MLJET ISALND, Croatia - It may be pretty to look at, but you might be a little intimidated if you came face to face with it.
This giant jelly fish, all 11 and half feet of it, was found in the southern part of the Adriatic Sea.
It's a type of jellyfish rarely seen in the Adriatic and it was videotaped at a depth of more than 90-feet.
It's a carnivorous jellyfish that eats other sea creatures and other jellyfish too.
Some call it a compass jellyfish because the markings on its body radiate from the center like a compass.
Friday, May 14, 2010
Jellyfish and Oil Don't Mix
Photos by Carolyn Cole from the LATimes.com
Dead jellyfish float in the waters off the Chandeleur Islands.
Oil surrounds parts of Louisiana's Chandeleur Islands in the Gulf of Mexico.
A boat makes its way along the edge of the oil spill in the Gulf of Mexico near the Chandeleur Islands.
Jellyfish can survive and even thrive with a lot of crap that civilization throws their way. But not oil.
Dead jellyfish float in the waters off the Chandeleur Islands.
Oil surrounds parts of Louisiana's Chandeleur Islands in the Gulf of Mexico.
A boat makes its way along the edge of the oil spill in the Gulf of Mexico near the Chandeleur Islands.
Jellyfish can survive and even thrive with a lot of crap that civilization throws their way. But not oil.
Monday, March 08, 2010
"Growing low-oxygen zones in oceans..."
Lower levels of oxygen in the Earth's oceans, particularly off the United States' Pacific Northwest coast, could be another sign of fundamental changes linked to global climate change, scientists say.
They warn that the oceans' complex undersea ecosystems and fragile food chains could be disrupted.
In some spots off Washington state and Oregon , the almost complete absence of oxygen has left piles of Dungeness crab carcasses littering the ocean floor, killed off 25-year-old sea stars, crippled colonies of sea anemones and produced mats of potentially noxious bacteria that thrive in such conditions.
Areas of hypoxia, or low oxygen, have long existed in the deep ocean. These areas — in the Pacific, Atlantic and Indian oceans — appear to be spreading, however, covering more square miles, creeping toward the surface and in some places, such as the Pacific Northwest , encroaching on the continental shelf within sight of the coastline.
"The depletion of oxygen levels in all three oceans is striking," said Gregory Johnson , an oceanographer with the National Oceanic and Atmospheric Administration in Seattle.
In some spots, such as off the Southern California coast, oxygen levels have dropped roughly 20 percent over the past 25 years. Elsewhere, scientists say, oxygen levels might have declined by one-third over 50 years.
"The real surprise is how this has become the new norm," said Jack Barth , an oceanography professor at Oregon State University . "We are seeing it year after year."
Barth and others say the changes are consistent with current climate-change models. Previous studies have found that the oceans are becoming more acidic as they absorb more carbon dioxide and other greenhouse gases.
"If the Earth continues to warm, the expectation is we will have lower and lower oxygen levels," said Francis Chan , a marine researcher at Oregon State .
As ocean temperatures rise, the warmer water on the surface acts as a cap, which interferes with the natural circulation that normally allows deeper waters that are already oxygen-depleted to reach the surface. It's on the surface where ocean waters are recharged with oxygen from the air.
Commonly, ocean "dead zones" have been linked to agricultural runoff and other pollution coming down major rivers such as the Mississippi or the Columbia . One of the largest of the 400 or so ocean dead zones is in the Gulf of Mexico , near the mouth of the Mississippi.
However, scientists now say that some of these areas, including those off the Northwest, apparently are linked to broader changes in ocean oxygen levels.
The Pacific waters off Washington and Oregon face a double whammy as a result of ocean circulation.
Scientists have long known of a natural low-oxygen zone perched in the deeper water off the Northwest's continental shelf.
During the summer, northerly winds aided by the Earth's rotation drive surface water away from the shore. This action sucks oxygen-poor water to the surface in a process called upwelling.
Though the water that's pulled up from the depths is poor in oxygen, it's rich in nutrients, which fertilize phytoplankton. These microscopic organisms form the bottom of one of the richest ocean food chains in the world. As they die, however, they sink and start to decay. The decaying process uses oxygen, which depletes the oxygen levels even more.
Southerly winds reverse the process in what's known as down-welling.
Changes in the wind and ocean circulation since 2002 have disrupted what had been a delicate balance between upwelling and down-welling. Scientists now are discovering expanding low-oxygen zones near shore.
"It is consistent with models of global warming, but the time frame is too short to know whether it is a trend or a weather phenomenon," Johnson said.
Others were slightly more definitive, quicker to link the lower oxygen levels to global warming rather than to such weather phenomena as El Nino or the Pacific Decadal Oscillation, a shift in the weather that occurs every 20 to 30 years in the northern oceans.
"It's a large disturbance in the ecosystem that could have huge biological changes," said Steve Bograd , an oceanographer at NOAA's Southwest Fisheries Science Center in Southern California.
Bograd has been studying oxygen levels in the California Current, which runs along the West Coast from the Canadian border to Baja California and, some scientists think, eventually could be affected by climate change.
So far, the worst hypoxic zone off the Northwest coast was found in 2006. It covered nearly 1,200 square miles off Newport, Ore. , and according to Barth it was so close to shore you could hit it with a baseball. The zone covered 80 percent of the water column and lasted for an abnormally long four months...
Some species, such as jellyfish, will like the lower-oxygen water. Jumbo squid, usually found off Mexico and Central America , can survive as oxygen levels decrease and now are found as far north as Alaska .
They warn that the oceans' complex undersea ecosystems and fragile food chains could be disrupted.
In some spots off Washington state and Oregon , the almost complete absence of oxygen has left piles of Dungeness crab carcasses littering the ocean floor, killed off 25-year-old sea stars, crippled colonies of sea anemones and produced mats of potentially noxious bacteria that thrive in such conditions.
Areas of hypoxia, or low oxygen, have long existed in the deep ocean. These areas — in the Pacific, Atlantic and Indian oceans — appear to be spreading, however, covering more square miles, creeping toward the surface and in some places, such as the Pacific Northwest , encroaching on the continental shelf within sight of the coastline.
"The depletion of oxygen levels in all three oceans is striking," said Gregory Johnson , an oceanographer with the National Oceanic and Atmospheric Administration in Seattle.
In some spots, such as off the Southern California coast, oxygen levels have dropped roughly 20 percent over the past 25 years. Elsewhere, scientists say, oxygen levels might have declined by one-third over 50 years.
"The real surprise is how this has become the new norm," said Jack Barth , an oceanography professor at Oregon State University . "We are seeing it year after year."
Barth and others say the changes are consistent with current climate-change models. Previous studies have found that the oceans are becoming more acidic as they absorb more carbon dioxide and other greenhouse gases.
"If the Earth continues to warm, the expectation is we will have lower and lower oxygen levels," said Francis Chan , a marine researcher at Oregon State .
As ocean temperatures rise, the warmer water on the surface acts as a cap, which interferes with the natural circulation that normally allows deeper waters that are already oxygen-depleted to reach the surface. It's on the surface where ocean waters are recharged with oxygen from the air.
Commonly, ocean "dead zones" have been linked to agricultural runoff and other pollution coming down major rivers such as the Mississippi or the Columbia . One of the largest of the 400 or so ocean dead zones is in the Gulf of Mexico , near the mouth of the Mississippi.
However, scientists now say that some of these areas, including those off the Northwest, apparently are linked to broader changes in ocean oxygen levels.
The Pacific waters off Washington and Oregon face a double whammy as a result of ocean circulation.
Scientists have long known of a natural low-oxygen zone perched in the deeper water off the Northwest's continental shelf.
During the summer, northerly winds aided by the Earth's rotation drive surface water away from the shore. This action sucks oxygen-poor water to the surface in a process called upwelling.
Though the water that's pulled up from the depths is poor in oxygen, it's rich in nutrients, which fertilize phytoplankton. These microscopic organisms form the bottom of one of the richest ocean food chains in the world. As they die, however, they sink and start to decay. The decaying process uses oxygen, which depletes the oxygen levels even more.
Southerly winds reverse the process in what's known as down-welling.
Changes in the wind and ocean circulation since 2002 have disrupted what had been a delicate balance between upwelling and down-welling. Scientists now are discovering expanding low-oxygen zones near shore.
"It is consistent with models of global warming, but the time frame is too short to know whether it is a trend or a weather phenomenon," Johnson said.
Others were slightly more definitive, quicker to link the lower oxygen levels to global warming rather than to such weather phenomena as El Nino or the Pacific Decadal Oscillation, a shift in the weather that occurs every 20 to 30 years in the northern oceans.
"It's a large disturbance in the ecosystem that could have huge biological changes," said Steve Bograd , an oceanographer at NOAA's Southwest Fisheries Science Center in Southern California.
Bograd has been studying oxygen levels in the California Current, which runs along the West Coast from the Canadian border to Baja California and, some scientists think, eventually could be affected by climate change.
So far, the worst hypoxic zone off the Northwest coast was found in 2006. It covered nearly 1,200 square miles off Newport, Ore. , and according to Barth it was so close to shore you could hit it with a baseball. The zone covered 80 percent of the water column and lasted for an abnormally long four months...
Some species, such as jellyfish, will like the lower-oxygen water. Jumbo squid, usually found off Mexico and Central America , can survive as oxygen levels decrease and now are found as far north as Alaska .
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