The intricate symbiotic relationship between reef building corals and algae seem to rely on a delicate communication process between the algae and the coral, where the algae is constantly telling the coral that the algae belongs inside it, and that everything is fine. Without this communication, the algae would be treated as any other invader, e.g. a parasite, and be expelled by the coral’s immune system.

Researchers now fear that increased water temperature will impair this communication system, something which might prove to be the final blow for corals already threatened by pollution, acidification, overfishing, dynamite fishing, and sedimentation caused by deforestation.

According to a new report, a lack of communication is likely to be the underlying cause of coral bleaching and the collapse of coral reef ecosystems around the world.

Reef building corals can defend themselves and kill plankton for food, but despite this they can not survive without the tiny algae living inside them. Algae, which are a type of plants, can do what corals can’t – use sunlight to produce sugars and fix carbon through photosynthesis.

“Some of these algae that live within corals are amazingly productive, and in some cases give 95 percent of the sugars they produce to the coral to use for energy,” said Virginia Weis, a professor of zoology at Oregon State University. “In return the algae gain nitrogen, a limiting nutrient in the ocean, by feeding off the waste from the coral. It’s a finely developed symbiotic relationship.

If this relationship were to collapse, it would be death sentence for the reef building corals.

Even though the coral depends on the algae for much of its food, it may be largely unaware of its presence, said Weis. We now believe that this is what’s happening when the water warms or something else stresses the coral – the communication from the algae to the coral breaks down, the all-is-well message doesn’t get through, the algae essentially comes out of hiding and faces an immune response from the coral.”

This internal communication process, Weis said, is not unlike some of the biological processes found in humans and other animals.

Researchers now hope that some of the numerous species of reef building corals found globally and their algae will be more apt at handling change.

“With some of the new findings about coral symbiosis and calcification, and how it works, coral biologists are now starting to think more outside the box,” Weis said. “Maybe there’s something we could do to help identify and protect coral species that can survive in different conditions. Perhaps we won’t have to just stand by as the coral reefs of the world die and disappear.”

The new research has been published in the most recent issue of the journal Science and was funded in part by the U.S. National Science Foundation.

Genetic pattern analysis strongly suggests that California and British Columbia urchins are not connected via larval dispersal and comprise two distinct populations. Sea urchins have one of the longest larval periods of any known marine invertebrate and it has therefore been tempting to assume that ocean currents must be mixing urchin larvae all over the place, making it difficult for any distinct populations to form. But research results from the University of California now indicate that these two Pacific populations are two clearly separated ones.

Sea urchins –  Picture from the Red Sea

Together with former* graduate student Celeste Benham, marine biology professor Ron Burton of the University of California at San Diego have analyzed 500 adult sea urchins from Californian waters across five microsatellite markers and then compared the genetic patterns to an existing, similar database of 1,400 urchins from British Columbia. The Californian specimens were collected off the coast of San Diego, Los Angeles and Mendocino counties.

The genetic signatures found by Burton and Benham strongly suggest that the southern and northern populations are not connected via larval dispersal.

“From my evolutionary perspective, our results are important because they imply that, even on long time scales, there is no mixing, Burton explains. This means there is at least the potential for populations to adapt to different ocean conditions and gradually diverge. This is the first step in the two populations potentially becoming different species.”

This is the first time scientists have detected any population structure in the species. Similar studies carried out in the past have used fewer genetic markers and found no population genetics structure in the species despite having tested many different patches across its range.

“The take-home message of this study is that if you use more markers and newer techniques you will find some population differentiation that before nobody found,” says Burton.

* Benham is now a research assistant at the marine mammal laboratory at Hubbs-SeaWorld Research Institute in San Diego.

“Every single spot of the ocean along the West Coast is affected by 10 to 15 different human activities annually”, says Ben Halpern, a marine ecologist at the National Center for Ecological Analysis and Synthesis (NCEAS) at the University of California at Santa Barbara.

In a two-year long study, Halpern and his colleagues have documented the way humans are affecting the ocean off the West Coast of the United States. The research team has overlaid data on the location and intensity of 25 human derived sources of ecological stress, including commercial and recreational fishing, land-based sources of pollution, and climate change. The information has been used to construct a composite map of the status of West Coast marine ecosystems.

“We found two remarkable and unexpected results in this research,” says Halpern. “Ocean management needs to move beyond single-sector management and towards comprehensive

ecosystem-based management if it is to be effective at protecting and sustaining ocean health. Also, the global** results for this region were highly correlated with the regional results, suggesting that the global results can provide valuable guidance for regional efforts around the world.”

The study results show that hotspots of cumulative impact are located in coastal areas close to urban centres and heavily polluted watersheds.

“This important analysis of the geography and magnitude of land-based stressors should help focus attention on the hot-spots where coordinated management of land and ocean activities is needed,” said Phillip Taylor, section head in NSF’s* Division of Ocean Sciences.

You can find more information in the article from the research team published in the journal Conservation Letters on May 11. The project was conducted at NCEAS, which is primarily funded by NSF’s Division of Environmental Biology.

* National Science Foundation (NSF)

** The lead scientists on the U.S. study have already carried out a similar analysis on a global scale; the results were published last year in Science.

Thanks to the efforts of local resident Pak Dodent, coral destroyed around Sumatra by the 2004 tsunami is now making a remarkably recovery.

Dodent lives on the island of Pulau Wey off the north coast of Sumatra and the narrow channel between his small village Ibioh and a nearby island was particularly devastated by the enormous forces unleashed by the tsunami.

“It was like a washing machine out there and all of the coral was broken,” Dodent explained to a reporter from the Telegraph. Afterwards I thought to myself what can I do to make the coral grow again and I started to experiment.“

After some experimentation, Dodent decided to aid the corals by dropping concrete mounds over the sandy bottom, since reef building corals need a suitable surface to attach them selves to. He creates the concrete mounds by pouring concrete into a bucket, and he also embeds a plastic bottle or tube into the concrete so that a part of the plastic sticks up.

When the concrete is set, the devoted reef gardener drops his mounds by boat in the shallow waters near the beach and leaves them there for a month to allow any potentially harmful chemicals present in the concrete to dissipate. After that, he carefully begins to transplant corals to the mounds by harvesting small patches of corals from the healthy reef on the far side of the island. “I am careful to only take a little from here and there so that I don’t affect the healthy eco system”, says Dodent.

Dodent uses cable ties to attach the transplants to the plastic bottles and tubes to prevent the corals from being dislocated by water movements.

Almost four years after the tsunami, Dodent’s coral garden is now covered with coral and has attracted an abundance of fishes and other animals. The coral is thriving and there is virtually impossible to the underlying concrete mounds. The garden currently comprises over 200 square metres and is home to over 25 different species of coral.

To prevent algae from overgrowing the new coral and killing it, Dodent regularly cleans infested coral patches with a toothbrush, but fishes and other coral eating organisms will soon alleviate him of this task. “I monitor and clean it for one year, after that it is up to the fishes,” he says.

Dodent has now recently received a small grant from Fauna and Flora International to develop his project.

According to a new report from the World Bank, inefficiency, wastefulness and poor management of fishing fleets are causing immense economic losses world wide. The report The Sunken Billions: The Economic Justification for Fisheries Reform, which was launched at the World Bank headquarters in New York and discussed at the International Union for Conservation of Nature (IUCN) Congress in Barcelona, says it would be possible to save 50 billion USD a year through wide-ranging reforms.

According to the World Bank study, the two main reasons behind the massive losses are depleted fish stocks and fleet overcapacity. Depleted fish stocks make it more expensive to locate and catch fish, turning commercial fishing into a less efficient business. The fleet overcapacity adds to the problem through redundant investment and operating costs.

While calling for wide-ranging reforms – including a comprehensive restructuring of fishing methods, removal of subsidies, and a more responsible and impartial stewardship of the seas – the report also acknowledges that such an endeavour won’t be without political, social, and economic costs. The current ‘business as usual’ attitude would however be even more costly in the long run, since it would lead to a scenario where commercial fishing becomes a drain on society through extensive subsidies.

According to the report, the recent steep increase in fuel prices can not be blamed for the loss-making since the marine fishing industry has been in decline for a much longer period of time. Despite increased fishing efforts and increasingly high-tech fishing fleets, depleted fish populations have caused the global marine catch to stay at the same level for over a decade.

In addition to the recently proposed areas in the Pacific Ocean, (See this and this) president Bush now says he wants to find even more regions of the Pacific Ocean to protect.

This Friday, Bush made public that he has asked the secretaries of the Interior, Commerce and Defense to identify additional areas of the Pacific Ocean that could be eligible for conservation. He also revealed that the Monterey Bay National Marine Sanctuary will be expanded by 585 square nautical miles and come to include the Davidson Seamount. Davidson Seamount is a 42 km long underwater mountain located roughly 120 km southwest of Monterey, California. The seamount rises 2400 meters off the ocean floor, but its highest point is still more than a kilometre below the surface.

The lionfish is native to the tropical Indo-Pacific region, but this fish – also known as Dragon fish or Turkey fish – has now invaded the warmer coral regions of the Eastern Atlantic Ocean and Caribbean Sea.

To combat the problem around Bermuda, 31 volunteers have been issued special licenses by the Ministry of the Environment and Sports to engage in spear fishing of lionfish within the one mile limit that is legislated for spear fishing activities, The Royal Gazette reports.

“The Lionfish constitutes a real threat to Bermuda’s reef ecosystem and commercial fishery. It is incumbent on us in Bermuda to do all we can to protect our marine ecosystem. In fact, even though this problem is relatively new to Bermuda, we are already being hailed by other countries and international organisations as an example of proactive management of Lionfish.” minister of the Environment Elvin James said to The Royal Gazette.

Several species of fish the family Scorpaenidae are known as lionfish, but the species causing trouble around Bermuda is Pterois volitans. It is believed to have been introduced to the ecosystem by saltwater aquarists in Florida. In order to better understand Pterois volitans and the effect it might have as an invasive species, the Department of Conservation Services will be collecting Lionfish from local waters and study them.

If you see a lionfish in the waters around Bermuda, contact the Marine Conservation Officer at 293 4464 extension 146 or email lionfish@gov.bm. The Marine Conservation Officer wish to know date, location and depth, and the approximate length of the fish (from snout to tail tip). The Marine Conservation Officer might need to contact you for further questions, so leave a phone number or email address.

Don’t try to catch the fish, because lionfish can give you a venomous sting with its fins. If you’re stung by a lionfish, seek medical attention right away. The sting is really painful.

You can read the full article in The Royal Gazette, Bermuda’s only daily newspaper.

http://www.royalgazette.com/siftology.royalgazette/Article/article.jsp?articleId=7d85e3330030009&sectionId=60