Coral

Corals depend on symbiotic algae to survive and build coral reefs. Increased ocean temperatures due to climate change can cause these symbiotic algae to be expelled from the coral, an event known as bleaching, which often leads to death.

Scientists from University of Miami placed corals in tanks and subjected them to increased water temperatures to gain insights into how they may react to global warming by replicating ocean conditions that would lead to both mild and severe coral bleaching.

PENRO chief Charlies Fabre has issued a warning to visiting scuba divers after at least two photos had been posted on Facebook by an environmentalist who frequented Apo Island showing a diver using a poker and touching corals. It turned out that this was a somewhat common practice among some scuba divers.

Fabre said he would ask the Protected Area Superintendent Efren Rombawa, who is also the chief of the Community Environment and Natural Resources Office on Apo Island, to look into the matter.

It was the first thorough exploration of the cold, oxygen-rich waters north of Bodega Head, a small promontory that lies along the California's Sonoma coast just 70 miles north of San Francisco. Submarine canyons, such as Bodega Canyon, extend from the continental shelf to the deep sea – making their exploration a difficult but worthwhile endeavour. The canyons are important because they act as a refuge for important species of fish and provide a habitat for sensitive species of deep-water corals and sponges.

Using the staghorn coral Acropora millepora as a model, scientists from the University of Southampton have found that the fluorescent pigments that are mostly responsible for coral colours act as sunscreens for the symbiotic algae that live in the coral tissue. These alga require light to produce sugars, which they can contribute to the nutrition of the corals in return for the shelter and the supply of nutrients that are provided by the coral host.

A scientist from Nova Southeastern University's Oceanographic Center found the coral while doing a survey for the environmental agency, which wanted a better map of shallow reef system.

The department of environmental protection wanted a better map of the coral's locations to improve the management of beach-widening, coastal development and other activities that could harm corals, as well as improve responses to incidents such as oil spills and illegal boat anchoring.

In a recent publication in the Proceedings of the National Academy of Sciences, or PNAS, Hellberg and his graduate student Carlos Prada investigate how corals specialize to particular environments in the ocean.

It is very well known that physical barriers and reproductive isolation can lead to the formation of new species on land, especially among plants and animals with short generation times such as insects and annual plants.

The coral Leptoseris is living 410 feet (125 meters) below the ocean's surface, a discovery that expedition leader Pim Bongaerts of the University of Queensland called "mind-blowing."

Bongaerts and his colleagues received funding from insurer the Catlin Group Limited to explore the Great Barrier Reef as part of an effort to understand how climate change is altering the oceans.

White syndrome' is a name given to a number of diseases exhibiting similar symptoms, such as such as white pox, white band and white plague disease. The causes of white syndrome are in many cases unknown. White syndrome has increased in abundance 20-fold in the last five years, with increases on inner, mid-shelf and outer-shelf reefs along the length of the Great Barrier Reef. It also had a major impact on Caribbean reefs. In areas of the Great Barrier Reef surveyed, white syndrome, along with skeletal eroding band, was the most common disease.

Scientists at the Max Planck Institute for Marine Microbiology from Bremen together with their colleagues from Australia, Sultanate of Oman and Italy have investigated how and why the corals die when exposed to sedimentation. According to their findings, oxygen depletion, together with an acidification of the environment, creates a chain reaction that leads to coral death.

However, at locations were there was excessive adverse impact (like pollution), the corals did not recover fully, even after eight years.
 
“You can imagine that when you are recovering from a sickness, it will take a lot longer if you don’t eat well or get enough rest,” said Jessica Carilli, a graduate student at Scripps Institution of Oceanography at UC San Diego.
 
“Similarly, a coral organism that must be constantly trying to clean itself from excess sediment particles will have a more difficult time recovering after a stressful condition like bleaching.”
 
Disease and overfishing also affected coral health. In places where there is overfishing, the population of bigger fishes like groupers are either significantly reduced or have vanished.
 
In the absence of these predatory fishes, other fish species thrive. One such species is the butterflyfish, which feed on coral and appear to be responsible for disease transmission amongst the corals.
 
In a study, scientists compared seven Marine Protected Areas [MPAs] where fishing had been banned for at least five years, and another seven neighbouring sites with similar diversity.
 
They discovered that the corals at the latter sites suffered more diseases; in some cases, the difference was twice as many. In addition, many butterflyfish were found at the sites where fishing was allowed, leading to a higher incidence of coral disease.