Tag Archives: Ocean


Barnacle glue works like human blood

barnaclesBarnacles are capable of attaching themselves to virtually any underwater surface; from whale skin and turtle shells to ship hulls and pier structures. Just how they manage to keep themselves anchored has remained a mystery; a multimillion mystery since barnacles increase fuel consumption by adding additional drag to the submerged parts of marine vessels. Scientists knew that the barnacles used a type of glue, but they didn’t understand how it worked and why it was so strong.

Traditionally, toxic paint has been used to keep the barnacles away but dry-docking huge cargo ships every so often to have them repainted is naturally expensive. Also, the toxic paint is not only affecting the barnacles; it is causing problems for entire ecosystems and many countries have therefore decided to ban or limit the use of some of the most harmful ones.

Using modern techniques such as force microscopy and mass spectrometry, a team of scientists from Duke University’s Marine Laboratory in Durham has now managed to find out how barnacles stick to surfaces; a discovery which they hope will lead to the development of more environmentally friendly anti-barnacle remedies.

The research team unveiled that barnacle glue from the species Amphibalanus amphitrite binds together much the same way as red blood cells bind together when our blood clots. When our blood clot, several different enzymes work together to form protein fibres that bind the cells together. In barnacle glue, similar enzymes – known as trypsin-like serine proteases – do the same thing. Interestingly enough, one of these enzymes are remarkably similar to Factor XIII, and essential blood clotting agent present in human blood.

We’ve found homologous enzymes in barnacles and humans, which serve the same function of clotting proteins underwater, despite roughly a billion years of evolutionary separation,” says research team member Dr Gary Dickinson.

Another team member, Professor Dan Rittschof, explains that this similarity does make evolutionary sense.

Virtually no biochemical pathway is brand new. Everything is related and really important pathways are used over and over,” says Rittschof. “Really key parts of those pathways can’t change because if they do, the pathway fails and the animal dies.”

According to Dickinson, it wouldn’t be surprising to find this glue in other organisms besides the barnacles.

The enzymes are highly conserved because they are very effective at what they do, ” says Dickinson. “There are bound to be a number of other organisms that use the same enzymes for the same purpose.”

For more information, read the article in The Journal of Experimental Biology.

http://jeb.biologists.org

Man made pollution a source of bio-available iron for oceanic organisms

Lack of iron is a limiting factor for plankton growth in many parts of the ocean, especially in the southern oceans and parts of the eastern Pacific. Scientists at the University of Leeds, UK, have now showed that acid in the atmosphere breaks down large particles of iron found in dust into small and highly soluble iron naonparticles; particles which can be easily absorbed and utilized by oceanic plankton.

Since plankton absorb carbon dioxide from the atmosphere, more available iron could trigger increased movement of carbon dioxide from the air to the ocean.

This could be a very important discovery because there’s only a very small amount of soluble iron in the ocean and if plankton use the iron nanoparticles formed in clouds then the whole flux of bioavailable iron to the oceans needs to be revised,” says Dr Zongbo Shi, lead author of the research from the School of Earth and Environment at the University of Leeds.

Polluting industries that causes a high degree of acidic particles to be present in clouds can therefore strangely enough simultaneously be combating global warming.

Man made pollution adds more acid to the atmosphere and therefore may encourage the formation of more iron nanoparticles,” says Dr Shi.

This process is happening in clouds all over the world, but there are particularly interesting
consequences for the oceans. What we have uncovered is a previously unknown source of
bioavailable iron that is being delivered to the Earth’s surface in precipitation,
” says Professor Michael Krom, the principal investigator of the research, also at the University of Leeds.

Miso soup kelp resists Californian eradication efforts

Undaria pinnatifida The invasive kelp Undaria pinnatifida is has now spread from Los Angeles to San Francisco Bay, despite eradication efforts.

Earlier, the northward spread of this sea weed – which can grow an inch a day and forms dense underwater forests – was believed to have been stopped at Monterey Bay, but this assumption turned out to be wrong when a biologist at the Smithsonian Environmental Research Center happened to notice a six-foot long piece of kelp attached to a boat in a yacht harbor in San Francisco Bay.

“I was walking in San Francisco Marina, and that’s when I saw the kelp attached to a boat,” said Chela Zabin, biologist at the Smithsonian Environmental Research Center in Tiburon, California. “It was six-foot long, and there is nothing here in the bay that gets to that size. I didn’t want to believe what it was, it’s depressing.”

Further investigation showed U. pinnatifida clinging not only to boat hulls in the marina but to docks and pier pilings as well.

U. pinnatifida was discovered in Los Angeles Harbour in 2000 and within a year reports of its presence had arrived from Catalina Island and Monterey Bay. A federal eradication program was put in place, but the funding dried up last year. Since then, volunteer divers have been the only ones combating the kelp.

Five quick facts about Undaria pinnatifida

• Undaria pinnatifida is a fast growing kelp native to the waters of Japan, China and South and North Korea.

• Within its native range it is an appreciate source of food and if you’ve ever tasted miso soup, this is what you were eating. The Japanese name for this species is wakame.

• U. pinnatifida has managed to establish itself in many different regions outside its native range, such as the Atlantic coast of Europe, the Mediterranean Sea, and the Argentinean coast. By attaching itself to vessel hulls it can hitchhike across the globe in search of new suitable habitats. This kelp can also enter ecosystems via imported oysters, and some people deliberately or accidently introduce U. pinnatifida to local ecosystems by cultivating it for cooking purposes.

• When U. pinnatifida spread to ecosystems not used to its presence, it can grow uncontrolled and prevent native kelp species from getting any sunlight. This can disturb the entire ecosystem.

• U. pinnatifida has been nominated to the list “100 worst invasive species in the world”.

Canada soon to complete world’s largest ocean observatory

neptuneIf everything goes according to plan, the world’s largest ocean observatory will be ready for use by late September, except for the instruments at one node which won’t be installed until next year.

“Scientists and staff at NEPTUNE Canada are delighted to begin the final phase of installation following a decade of planning,” says Dr. Chris Barnes, director of NEPTUNE Canada.

NEPTUNE Canada, the world’s most advanced cabled ocean observatory, consists of five 13-tonne nodes and more than 400 instruments and sensors that will be placed on the seafloor off the coast of British Columbia with the aid of three ships, one Remotely Operated Vehicle (ROV), and a team of scientists and marine engineers. The observatory will be attached to a loop of powered fibre-optic cable which was put in place in 2007.

NEPTUNE Canada will use the Internet to transmit information to land-based scientists across the world, thus making it possible for researchers to experiment and investigate the deep sea without having to get their feet wet (or die from the immense pressure). NEPTUNE Canada will also carry out long-term monitoring of ocean processes and events.

“This is truly transformative science,” says Dr. David Turpin, president of the University of Victoria. “At a time when our understanding of the oceans is clearly becoming more essential than ever, NEPTUNE Canada will play a leadership role in advancing our knowledge of the oceans in ways not previously possible. We are launching a new era of ocean exploration.”

NEPTUNE Canada has been designed to withstand the intense pressure and cold of the deep sea as well as trawlers and corrosive saltwater.

“Working with industry partners, we’ve developed a host of novel science experiments, advanced engineering and sensor technologies and innovative data management systems”, says Dr. Barnes. “This is a very exciting time for ocean science.”

A lot of the technology fitted to the observatory is cutting-edge solutions that are now being deployed for the very first time.

Much of the infrastructure for NEPTUNE Canada is being designed, manufactured and installed by Alcatel-Lucent and its main subcontractors. Other main partners are the University of Victoria, the research ship Atlantis operated by the Woods Hole Oceanographic Institution and the research ship Thompson operated by the University of Washington. The project is funded chiefly by the Government of Canada, the Canada Foundation for Innovation, the Natural Sciences and Engineering Research Council of Canada, CANARIE, and the Government of British Columbia through the BC Knowledge Development Fund.

Will the future bring us Japanese super tuna?

A Japanese team of scientists are now announcing that they are close to completing genome sequencing of the Bluefin tuna. Once they have reached this goal, their next project will be to use their knowledge to create a tuna breeding program for a new type of tuna specially designed for aquacultures.

BLuefin tuna

The wild tuna populations have become severely depleted due to overfishing and the WWF has warned that the Atlantic Bluefin tuna will be eradicated within three years unless radical measures are taken to safeguard remaining specimens.

“We have already completed two computer sequencing runs and have around 60 per cent of the tuna genome,” says Dr. Kazumasa Ikuta, director of research at the Yokohama-based Fisheries Research Agency. “We expect to have the entire sequence in the next couple of months. We plan to use the sequence to establish a breeding programme for bluefin tuna as most aquaculture farmers presently use wild juveniles. We want to establish a complete aquaculture system that will produce fish that have good strength, are resistant to disease, grow quickly and taste delicious.”

The genome sequencing is the result of the collaborative efforts of scientists from Japan’s Fisheries Research Agency, Kyushu University, and The University of Tokyo.

Plastic rubbish a problem says UN study

The United Nations Environment Program has now released the first study of the impact of marine debris throughout the world’s oceans. The report found that plastic, especially bags and polyethylene terephthalate (PET) bottles, makes up more than 80 per cent of all rubbish found in the oceans. The UN report, titled “Marine Litter: a Global Challenge”, also found that plastic bags alone constitute almost 10 percent of the rubbish.

Some of the litter, like thin-film, single-use plastic bags, which choke marine life, should be banned or phased out rapidly everywhere because there is simply zero justification for manufacturing them any more, anywhere,” says UN environment program executive director Achim Steiner.

The United Nations are not the only ones worried about the enormous amounts of plastic entering our marine ecosystems each year. In Australia, plastic bags and other marine debris are a direct threat to 20 marine species according to the Federal Government’s Threatened Species Scientific Committee who has listed plastic bags as a “key threatening process” under the Environment Protection and Biodiversity Conservation Act 1999. Marine animals threatened by our reckless use of plastics include iconic creatures like the Blue whale, Loggerhead turtle, and Tristan albatross.

Dubai’s largest reef moved 15 km

Dubai‘s largest reef, consisting of over 1,100 coral-encrusted rocks, has been moved to a new location to protect it from future development. Details of the relocation have been kept secret for more than a year to ensure its success, and the transfer was therefore not announced until today, on World Environment Day.


not the reef in the article!


Oddly enough, no one seems to have known about the existence of the reef until Dubai real estate development company Nakheel conducted an environmental assessment of Dubai Dry Docks’ breakwater.

What we found [in the initial assessment] was the biggest coral reef in Dubai and an area of extreme importance, said marine biologist John Burt, Assistant Professor at Zayed University, who was brought on board as an independent expert. Because of the conditions in the Gulf – where the water temperature can reach 35C and drop to 15C – coral has difficulty establishing itself. However, it has learned to adapt and we believed it was important to do everything we could to protect this reef.”

Moving 1,129 rocks

Traditional methods of moving corals were quickly dismissed, since they typically result in the death of up to 30 percent of the corals. Instead, Nakheel and their team of engineers and scientists decided to remove, lift and transport the corals by barge without ever taking them out of the water.

Traditionally, when coral is moved it is chiselled or drilled from rocks, placed in baskets and shipped to a new location,” said Brendan Jack, Head of Sustainability and Environment for Nakheel Northern Projects. “That wasn’t open to us because each of the rocks was encased in coral, so we went back to the drawing board to find an engineering solution. Nothing like this has ever been attempted before and we are very pleased with the outcome.”

The project took five weeks to complete and involved engineers and divers drilling an iron bolt into each and every one of the rocks and attaching it to a sling. After being hoisted from its resting place, each rock had its sling fastened to one of several mountings welded to the deck of a 90-metre barge. Thanks to this new method, the coral rocks could be moved to their new home at The World’s breakwater without ever leaving the water.

With no more than 20 rocks being transported to The World at a time; it took 50 days to move the 1,129 rocks – each of them weighing about five tonnes. Sadly enough, some rocks had to be left behind since they could not be reached by the marine crane.

We could not take all of the coral,” said Burt. In some places the water was too shallow for the crane so the rocks had to be left. I believe once development around the Dry Docks breakwater begins the remaining coral has no chance of survival.”

The result

Initial studies of the relocated coral have been very promising and so far the project seems to have been successful. As mentioned above, up to 30 percent of the coral usually give up the ghost when traditional relocation methods are used but in the case of the Dubai reef only 7 percent of the corals have died. Independent scientific study of the coral is continuing and a scientific peer-reviewed research paper will be published once the study is complete in the coming months.

The future

The World, where the coral reef is now residing, is a man made archipelago of 300 islands constructed in the shape of a world map and located 4 km off the coast of Dubai. The total area now covered by coral at The World is 6,560 square metres and this number may increase as corals begin to colonize nearby surfaces.

A number of the dominant corals, now at The World, are ‘broadcast spawners’ and their reproductive activities could result in the development of coral on nearby rocks”, said a Nakheel spokesman.

The exact location of the relocated reef is still being kept secrete to avoid attracting commercial and recreational fishermen. However, once the new coral colony is firmly established it may be opened up for scuba diving and similar activities.

Little time left to save the worlds remaining oyster reefs; 85 percent have already been lost

oysterThe first-ever comprehensive global report on the state of shellfish has been released by The Nature Conservancy at the International Marine Conservation Congress in Washington, DC.

This one of its kind report is a collaborative work carried out by scientists from five different continents employed by academic and research institutions as well as by conservation organizations.

The report, which focuses primarily on the distribution and condition of native oyster reefs, show that 85 percent of oyster reefs have been completely destroyed worldwide and that this type of environment is the most severely impacted of all marine habitats.

In a majority of individual bays around the globe, the loss exceeds 90 percent and in some areas the loss of oyster reef habitat is over 99 percent. The situation is especially dire in Europe, North America and Australia where oyster reefs are functionally extinct in many areas.

We’re seeing an unprecedented and alarming

decline in the condition of oyster reefs, a critically

important habitat in the world’s bays and estuaries,”

says Mike Beck, senior marine scientist at The Nature

Conservancy and lead author of the report.

Many of us see oysters as a culinary delight only, but oyster reefs provide us humans with a long row of valuable favours that we rarely think about. Did you for instance known that oyster reefs function as buffers that protect shorelines and prevent coastal marshes from disappearing, which in turn guard people from the consequences of hurricanes and other severe storm surges? Being filter feeders, oysters also help keep the water quality up in the ocean and they also provide food and habitat for many different types of birds, fish and shellfish.

Even though the situation is dismal, there is still time to save the remaining populations and aid the recuperation of damaged oyster reefs. In the United States, millions of young Olympia oysters have been reintroduced to the mudflats surrounding Netarts Bay in Oregon, in an effort to re-create a self-sustaining population of this native species. The project is a joint effort by government and university scientists, conservation groups, industry representatives, and local volunteers.

With support from the local community and other partners, we’re demonstrating that shellfish restoration really works”, says Dick Vander Schaaf, Oregon director of coast and marine conservation for the Conservancy. “Expanding the effort to other bays and estuaries will help to ensure that the ecological benefits of oyster reefs are there for future generations.”

If wish to learn more about the global oyster reef situation, you can find the report here.

World’s first Bigeye tuna farm may be placed off the coast of Hawaii

A Hawaiian company wants to build the world’s first commercial Bigeye tuna farm, in hope of creating a sustainable alternative to wild-caught big eye.

Bigeye tuna, Thunnus obesus, is the second most coveted tuna after the famous Bluefin tuna and the wild populations have been seriously depleted by commercial fishing fleets. As Bluefin is becoming increasingly rare due to over-fishing, consumers are turning their eyes towards Thunnus obesus – which naturally puts even more stress on this species that before.

In 2007, fishermen caught nearly 225,000 tons of wild Bigeye in the Pacific. Juvenile bigeye tuna like to stay close to floating objects in the ocean, such as logs and buoys, which make them highly susceptible to purse seine fishing in conjunction with man-made FADs (Fish Aggregation Devices). The removal of juvenile specimens from the sea before they have a chance to reach sexual maturity and reproduce is seriously threatening the survival of this tuna species.

All indications are we’re on a rapid race to deplete the ocean of our food resources,” said Bill Spencer, chief executive of Hawaii Oceanic Technology Inc. “It’s sort of obvious _ well, jeez we’ve got to do something about this.”

Techniques to spawn and raise tuna fry are still being tentatively explored by scientists in several different countries, including Australia and Japan. As of today, most tuna farms rely on fishermen catching juvenile fish for them, but Hawaii Oceanic Technology plans to artificially hatch Bigeye tuna at a University of Hawaii lab in Hilo.

Once the young tunas from the lab have grown large enough, they will be placed in the 12-pen tuna farm that Hawaii Oceanic is planning to build roughly 3 miles off Big Island’s west coast. Each pen will have a diameter of 50 metres (168 feet) and the entire farm will be spread out over one square kilometre (250 acres). If everything goes according to plan, this project will yield 6,000 tons of Bigeye per annum. The fish will not be harvested until it reaches a weight of at least 45 kg (100 lbs).

In an effort to avoid many of the common problems associated with large scale commerical fish farmning, Hawaii Oceanic Technology will place their pens at a depth of 1,300 feet (400 metres) where currents are strong. The company also plans to keep their pens lightly stocked, since dense living conditions are known to increase the risk of disease in fish farms.

Farming pens can cause problems for the environment if fish waste and left-over food is allowed to collect under the pens, suffocating marine life living beneath. Other problems associated with fish farming are the release of antibiotics into the water and the escape of invasive species.

Fish farms can also put pressure on fish further down in the food chain since vast amounts of food is necessary to feed densely packed fish pens, and Peter Bridson, aquaculture manager at the Monterey Bay Aquarium in California, is concerned about how much fish meal the Hawaiian farm will use need to feed its tuna.

You kind of have to come back to the whole debate on whether these fish are the right thing for us humans to be eating,” said Bridson. “There are lots of other things which have a lower impact in terms of how they are farmed.”

Spencer shares this concern and says Hawaii Oceanic wish to eventually develop other ways of feeding their fish, e.g. by creating food from soybeans or algae. It might also be possible to decrease the need for fish meal by recycling fish oil from the farm itself.

We’re concerned about the environmental impact of what we’re doing,” Spencer said. “Our whole goal is to do this in an environmentally responsible manner.”

Will captive bred tuna save depleted wild populations?

An important step in the ground-breaking Clean Seas Tuna breeding program was taken today when millions of dollars worth of Southern Bluefin Tuna was airlifted from sea pens off South Australia’s Eyre Peninsula to an on-shore breeding facility at Arno Bay.

The Southern Bluefin Tuna is a highly appreciated food fish and the remaining wild populations are continuously being ravished by commercial fishing fleets, despite the species status as “critically endangered” on the IUCN Red List of Threatened Species.

The Australian tuna breeding program is the first of its kind and will hopefully help ease the strain on wild populations. The air transfer was made to provide the breeding program with an egg supply ahead of the spawning period.

bluefin tuna

As reported earlier, the Australian company Clean Seas Tuna managed to successfully produce Southern Bluefin Tuna fingerlings in March this year and they are now hoping to commence commercial production of the species no later than October.

WWF Australia’s fisheries program manager Peter Trott says any advancement that would reduce pressure on wild tuna stocks is welcome, but he also cautions against the environmental problems associated with large-scale aquacultures. It is for instance common to use other fish to feed farmed fish, which can put pressure on wild fish populations.