Jellyfish swarms: menacing or misunderstood?

New Scientist : unusually high concentrations of mauve stinger jelllyfish have been discovered near the Balearic Islands in Spain and in other parts of the Mediterranean (July 2007)

From LiveScience

They sting, even kill, swimmers. They block the cooling systems of power plants. They clog fishing nets and kill penned salmon.

In recent years, reports of havoc caused by swarms of jellyfish have inspired speculation that these simple, otherworldly creatures are capitalizing on changes we have brought to ocean ecosystems.

Scientists are finding we could be jellyfish's potential benefactors. Overfishing relieves them of competition and predators. Nutrient-rich pollution can cause phytoplankton blooms, providing feasts for some jellies and reducing the water's oxygen content, which could favor their high tolerance for low oxygen. The warmth of climate change could foster expansion among some species. We transport invasive species to new environments, where they thrive. And coastal development provides new shelter for the jellies' stationary life stage, called a polyp.

An article called "The Jellyfish Joyride" published in 2009 in the journal Trends in Ecology and Evolution, discusses the theory that, without a change on our part, these pressures could push ecosystems topped by fish and marine mammals to devolve into ones dominated by jellyfish, as they may have been 500 million years ago.

It is exactly the type of summary Steven Haddock dislikes.

Too easily villainized?

As Haddock, who studies gelatinous plankton at the Monterey Bay Aquarium Research Institute (MBARI) in California, sees it, reports on jellies' potential to overrun the seas resemble monster movies, inaccurately portraying and unfairly demonizing these creatures.

"So you end up with this kind of imaginary animal that has all these properties, which actually no one jellyfish has," Haddock said. "Basically, jellyfish need to eat, and jellyfish are eaten by things as well, so they are part of a healthy ecosystem."

The term "jellyfish" is a slippery one. In general use, it encompasses two groups: Cnidaria, a diverse group of animals armed with stinging cells, which include corals and true jellies — typically, the gelatinous creatures beachgoers encounter. The others are the Ctenophores or comb jellies, which use rows of tiny hairs, called cilia, to swim — and they don't sting. Fossil evidence of both dates back to the Cambrian Period, which lasted from 543 million to 490 million years ago.

Blooms occur when polyps, the early life stage, of some Cnidaria jellies bud off to form the free-floating, umbrella-shaped medusae, which we think of as jellyfish. The polyps bud simultaneously, and one can produce many medusae, creating – depending on one's perspective – blooms or swarms of jellies. Comb jellies, hermaphrodites that release eggs and sperm simultaneously, can also create blooms when they reproduce.

In Japan, conflicts with jellyfish have climbed in recent years, as populations of moon jellies and the giant Nomura's jellyfish, which grow up to 6.7 feet (2 meters) in diameter, have clogged fishing nets and power-plant intakes.

While there is no doubt that these jellies are showing up more frequently in Japanese waters, it's not clear whether the blooms are more intense than years prior, because scientists cannot determine the population sizes, according to Shin-ichi Uye, a professor at the Graduate School of Biosphere Science at Hiroshima University.

Based on the seeming increase in blooms around Japan and elsewhere in the East Asian seas, Uye suspects the increases are global in scale and attributable to human activities like overfishing, coastal construction and nutrient pollution, as well as warming waters.

"However, I admit that the data are not sufficient enough" to conclude that the phenomenon is global, he told LiveScience in an e-mail. "In fact, I paid no attention to jellyfish until they became increasingly problematic in fisheries in [the] 1990s."

No solid baseline

Scientific studies of jellyfish increased toward the end of the last century, but they were significantly outpaced by jellyfish stories in the popular press, indicating the hype may be media-driven, said Rob Condon, one of the lead investigators for the National Center for Ecological Analysis and Synthesis jellyfish working group. The group is examining the hypothesis that increases in jellyfish blooms are occurring worldwide.

A conclusion would be premature, according to Condon.

"The big thing here is an 'if,' and the jury is still out on this," he said. "I say, 'Show me the numbers.' Undoubtedly there are localized areas where blooms have increased. ... On a global scale, we don't know enough about jellyfish populations, their biology, their distribution, to make a judgment."

His group is trying to get to the bottom of this, looking at the limited data available both from government and scientific reports, and building a database that will outlive the two-year project. Public outreach is also part of the mission; anyone can submit a sighting on a website (jellywatch.org), and the group is holding an outreach event in Santa Barbara, Calif., on Nov. 20.

Because long-term data on jellyfish populations are limited, Lucas Brotz, a graduate student at the University of British Columbia, also has been looking at anecdotal information — reports in newspapers or from those who work at sea. He said he is seeing evidence of population increases but is not yet prepared to say if they are significant.

"One of the problems with identifying changes in jellyfish populations is they fluctuate with so much variability. One year you see a million, and the next year there won't be any," Brotz said.

No simple answers

Although researchers have attempted to correlate environmental changes with jellyfish populations, it's often difficult to draw a straight line between them.

There is evidence that some species of jellyfish increase or expand as waters warm. However , a complex scenario played out 10 years ago in the Bering Sea, near Alaska, contradicts that.

Trawl data collected by the Alaska Fisheries Science Center revealed that numbers of jellyfish, primarily the sea nettle, grew rapidly throughout the 1990s in the Bering Sea, while temperatures were moderate. The catches peaked in the summer of 2000, at about 40 times larger than in 1982, and the jellyfish also expanded their range. Then they began to decline, while the sea warmed markedly.

The decline may have occurred when the jellyfish food supply — fish and tiny floating animals called zooplankton — could no longer support their growing appetites, according to a 2008 study in the journal Progress in Oceanography. When conditions for zooplankton blooms were optimal, the jellyfish populations grew.

A similarly complex relationship between jellyfish and certain fish — which eat each other's young — may give the jellyfish an advantage in overfished waters. This phenomenon may have suppressed the recovery of Namibia's sardine and anchovy fisheries after they collapsed, according to Mark Gibbons, a plankton biologist at the University of the Western Cape in South Africa.

There is also a large unknown factoring into the population changes seen in the Bering Sea, since scientists have little information about where jellyfish polyps bud off to form the familiar medusa and about the conditions needed for the life-stage change.

"Our understanding of the basic polyp life history is almost negligible," Gibbons said. It is known that polyps can stay attached for very long periods of time, and if the environment becomes hostile they can effectively shut down and then "come back to life." They can also bud off more polyps under certain conditions. However, the factors influencing their behavior are poorly understood in most species, he wrote in an e-mail to LiveScience.

Unfairly villainized?

Jellyfish blooms are nothing new; these sudden proliferations of medusa are recorded in the fossil record more than 500 million years ago. "So it is hard to know if that is any different than it was a long time ago," according to Haddock.

Haddock, also a member of the NCEAS working group, said he came across a 1925 study of jellyfish reproduction, which the author speculated would help explain the masses of jellyfish that had washed up onto the beach in Monterey Bay. "Even for him in 1925, it went without saying, yeah, we get these big jellyfish blooms all the time."

Links :

• The jellyfish joyride : causes, consequences and management responses to a more gelatinous future
• Ecojel : Understanding jellyfish in the Irish Sea
  

Her tale will go on: Titanic survivor's story sold at auction

From BBC

A woman's account of escaping the sinking Titanic in 1912 has sold for £20,000 at auction.

Laura Francatelli's story was published for the first time in early October.

It was bought by an Eastern European collector when it went under the hammer at Henry Aldrige and Son in Wiltshire at the weekend.

In it, Miss Francatelli described how she heard an "awful rumbling" as the liner went down and "screams and cries" from 1,500 drowning passengers.
“There was an awful rumbling when she went. Then came the screams and cries. I do not know how long they lasted”

Her account was recorded in a signed affidavit for the official British inquiry into the disaster.

The Titanic was built at Belfast's Harland & Wolff shipyard. She was billed as "unsinkable".

But, on her maiden voyage to New York on 15 April 1912, she hit an iceberg in the Atlantic Ocean and sank, killing 1,521 people.

Miss Francatelli, who was 31 at the time, was travelling with baronet Sir Cosmo Duff-Gordon and his wife Lady Lucy Christiana, as his secretary.

The account describes how they boarded one of the last lifeboats containing just five passengers and seven crew, admitting they did not consider going back for survivors.

Sir Cosmo later paid the crew members £5 each - now worth about £300 (342 euros) - which some have described as blood money for saving their lives.

Miss Francatelli said she woke her employers when water seeped into her cabin after the liner struck an iceberg on the night of 14 April.

She wrote: "A man came to me and put a life preserver on me assuring me it was only taking precautions and not to be alarmed.

"When we got on the top deck, the lifeboats were being lowered on the starboard side.

"I then noticed that the sea was nearer to us than during the day, and I said to Sir Cosmo Duff Gordon 'We are sinking' and he said 'Nonsense, come away'."

The group refused to go into a lifeboat at first as Sir Cosmo was not allowed on, as they were designated for women and children only. But they were then offered places on a smaller rowing boat.

"There were no other women there by that time. The officer saw us and ordered us in, and we said we would go if Sir Cosmo could come also," Miss Francatelli said.

"Just as they were lowering the boat, two American gentlemen came along the deck and got in also. The officers gave orders to us to row away from ship."

She said they "were a long way off" when they saw the Titanic go right up at the back and plunge down.

"There was an awful rumbling when she went. Then came the screams and cries. I do not know how long they lasted.

"We had hardly any talk. The men spoke about God and prayers and wives. We were all in the darkness."

She wrote how the survivors huddled in the bottom of the boat to keep warm until they were rescued two hours after the sinking by the ship Carpathia.

Miss Francatelli died in 1967. The document remained in her family until after her death and has since been owned by two private collectors.

An intelligent system for maritime surveillance has been created

From Carlos III University of Madrid

Researchers at the Universidad Carlos III de Madrid (UC3M) have designed a real application for maritime surveillance that is able to integrate and unify the information from different types of sensors and data in context through artificial intelligence and data fusion techniques.

The system has been designed by scientists from this Madrid university for Núcleo CC, a company which develops surveillance systems for the maritime and aeronautic sectors.
The first prototype will be used in the near future in Cape Verde (Africa).
Two types of sensors have been deployed there: a set of radars and a series of AIS (Automatic Identification System), which allow ships to communicate their position and give other relevant data on their location and characteristics.
These two types of sensors offer complementary data which can be fused in order to obtain better information as to what is happening in the maritime and coastal space of the area of interest.
This has been achieved by the scientists from the Applied Artificial Intelligence Group (GIAA) of UC3M, who have carried out the project “Fusión de Información en Tráfico Marítimo” (Information Fusion in Marine Traffic).

The results of this research, presented last July at the International Conference on Information Fusion in Edinburgh, Scotland, has been the creation of data fusion software which allows improved maritime surveillance to be carried out, simultaneously integrating the capabilities of the radars and the AIS localization stations deployed.
The objective is to guarantee security in the area by monitoring the different ships that are in a given maritime route which, at the same time is the entrance and exit of a commercial port.
"For that”, Jesus Garcia, one of the heads of the study from the UC3M Department of Information Technology, pointed out, “it is necessary to have a complete, accurate, and up to date picture, similar to that which is provided to air traffic controllers, of all the ships that are in the area of coverage to be able to adequately manage maritime traffic and to detect anomalies as much in advance as possible”.

The scientists developed a prototype which has been integrated into the company’s system, after having undergone validation tests to be able to execute in real time with the data supplied by its sensors.
It able to monitor 2,000 identifiable objectives between large and small vessels, with a capacity to process the data of up to 10 sensors and provide the exit with one second refresh time.
"Ships have to be able to localized 24 hours a day, 7 days a week, 365 days a year, independent of failures in the sensors or in the different intermediate mechanisms, and in some way, what this system attempts to do is guarantee that this can be done”, explained José Luis Guerrero, another of the GIAA group researchers, who worked on this project from the UC3M Colmenarejo Campus.
"In this way”, he continued”, we are able to make it so these vessels never lose their position thus avoiding collisions or any type of problem in information management regarding the movement dynamics of these ships”.

This first prototype opens the way for posterior analysis and development, as more data and information regarding its functioning under real conditions are obtained, the scientists noted, who are now researching how to apply this information fusion technology to fields such as robotics, in unmanned vehicle navigation, artificial vision, or environmental intelligence systems.
“In all of these areas”, Professor Jesus Garcia pointed out, “information fusion technology and infrastructure are necessary to combine the data from available sensors and the contextual information in each scenario”.

Humpback whale swims a quarter of the world

Humpback whales typically travel up to 5,000km between breeding grounds

From BBCNews

In a record-breaking journey, a female humpback whale has travelled across a quarter of the globe, a distance of at least 10,000km.

The event, reported in the Royal Society journal Biology Letters, is the longest documented movement by a mammal.

Its voyage was also twice the distance that the whales typically migrate each season to new breeding grounds.

Scientists say the extreme behaviour shows how "flexible" these animals are.

Explore and adapt

The female whale was spotted and photographed twice - once at its regular breeding ground in Brazil, then later off the coast of Madagascar.

The shortest distance between these two locations is 9,800km.

The research team, led by Dr Peter Stevick from the College of the Atlantic in Maine, US, thinks the whale may have travelled this far in two distinct journeys.

"If I had to guess, I'd say this animal did a normal migration to the Antarctic [to feed] and went to Madagascar from there," Dr Stevick told BBC News.

"If I were to draw a track for it, it would be from Brazil to the Southern Ocean and from there into the Indian Ocean."

The scientists were able to identify the animal from photographs that were taken of its tail, or fluke.

Each humpback whale has unique markings on the pale underside of its fluke.

The team is involved in a long-term study, collecting and examining the pictures of the whale flukes in an effort to develop a "big picture" of humpback behaviour and their migration patterns.

Such a long-distance movement between different breeding grounds is very rare.

And the fact that this was a female whale made the event even more unusual, as males are more commonly known to explore in order to find mates.

"Some exploration helps them to remain adaptable," explained Dr Stevick.

"If animals always returned to exactly the same place to breed, if anything happened to change that environment, they might not be able to adapt, so very occasional exploration could be beneficial for them."

The journey would have taken the animal at least several weeks and so far the scientists only have records of these two sightings.

"But we gather these research photographs from all over the globe," said Dr Stevick.

"So we're hopeful we will see this animal again, or see other animals doing related things."

Links :

• Nature : Humpback whale breaks migration record : swim from Brazil to Madagascar is longest known
• HuffingtonPost : Humpback whale swims 6,200 Miles, longest mammal migration recorded
  

More progress in reopening of Gulf waters for fishing

Revenge of the squid

From CNN

Nearly 7,000 more square miles of fishing waters were reopened in the Gulf of Mexico on Friday, leaving only 7 percent of federal waters in the region still closed to fishing operations, authorities said.

The ninth reopening since July 22 reflects continued progress on the cleanup in the aftermath of the April BP oil spill. Officials, however, caution much work remains.
"We are guardedly optimistic," said Roy Crabtree, Southeast regional administrator for the National Oceanic and Atmospheric Administration's Fisheries Service.

The commercial and recreational waters reopened Friday are nearly 200 nautical miles south of the Florida Panhandle, between the Florida-Alabama state line and Cape San Blas, Florida, federal response officials said.

Federal testing of seafood from opened fishing areas has not shown any problems.
"Tourists and consumers should know most Gulf waters are open for fishing and seafood from these waters is safe to eat," said Jane Lubchenco, NOAA's administrator.

At its peak, the area covered by the fishing closure was 88,522 square miles, or 37 percent of Gulf waters, NOAA said. A little more than 16,000 square miles remain closed.

For the most part, NOAA first concentrated on testing waters farthest from the well, believing they would be the soonest to reopen for fishing, Crabtree said.
"We also took into account the economic importance," of fishing to a community, he said, indicating that was most vital on the western side of the Mississippi River in Louisiana and off the coasts of Mississippi and Pensacola, Florida.

The overriding concern, however, was the number of days an area was exposed to the oil, he said.
Four "blocks" of gulf waters remain closed, he said.
Their close proximity to the well may mean it will take longer for them to be deemed safe. Crabtree said he is confident all areas will be reopened to fishing, but some waters may not get the all-clear until 2011.

"It's too soon to draw conclusions about the long-term impact of this," he said, citing continued testing on fish eggs and larvae near the ocean surface, sub-surface oil and oil in Louisiana's marshes.
Christine Patrick, also of the NOAA Fisheries Service, told CNN that more than 2,700 seafood samples went through rigorous sensory and chemical testing, and none came up positive for the presence of oil or dispersants.
"No samples have been taken from opened fishing areas that haven't passed those tests," Patrick said earlier this week.

In September, NOAA reported that scientists found a decline in oxygen levels in the Gulf of Mexico following the BP oil spill, but did not find any "dead zones" connected to the spill.
A dead zone in Chandeleur Sound off Louisiana appears to be unrelated to the spill, federal officials said.

Links :

• NOAA reopens nearly 7,000 square miles in the Gulf of Mexico to fishing