The Wildlife Conservation Society (WCS) and the International Institute for Geo-Information Science and Earth have developed a new scientific model that accurately maps where coral reefs are in the most trouble and identifies regions where reefs can be protected best. The model, which is being applied in areas throughout the Indian Ocean, is described in a recent issue of the UK-based journal Ecological Modelling.
The model synthesizes several ocean conditions, such as seawater temperatures, photosynthetic and ultraviolet light, winds and currents, and the concentration of microscopic plankton on the ocean’s surface. These data were factored into previous reports of coral stress or bleaching and were then used to map the distribution of these inhospitable conditions.
The researchers found that much of the northern Indian Ocean contains very stressful environments for corals and that half of its marine parks with the strictest regulations are found within these harsh areas. Areas of the Maldives and the Seychelles fall in the middle of the most severe conditions; these include some of the best coral reef parks and diving spots. In an area east and just north of Madagascar lie the least-stressed reefs, which include those off the islands of Mauritius, Rodriques, and Reunion. These are now among the reefs the model identifies as the highest priority for conservation.
Corals have been devastated in large areas across the world. Disappearing at rates up to 5.4 percent per year over the past 30 years, they are among the earliest victims of climate change. Bleaching, which climate change exacerbates, occurs when corals become so stressed that they eject the beneficial algae that give them their color. This eventually causes large sections of the reefs to lose much of their biodiversity.
“Despite the large areas in high and severe stress, the model suggests that there are some reefs with less stressful conditions and more reasons for hope,” said WCS researcher Dr. Timothy McClanahan, one of the study’s authors.
Source: Wildlife Conservation Society
Related stories:
Acidifying oceans add urgency to CO2 cuts
It's not just about climate change anymore. Besides loading the atmosphere with heat-trapping greenhouse gases, human emissions of carbon dioxide have also begun to alter the chemistry of the ocean—often called the cradle of life on Earth. The ecological and economic consequences are difficult to predict but possibly calamitous, warn a team of chemical oceanographers in the July 4 issue of
Science, and halting the changes already underway will likely require even steeper cuts in carbon emissions than those currently proposed to curb climate change.
Coral reefs may be protected by natural ocean thermostat
Natural processes may prevent oceans from warming beyond a certain point, helping protect some coral reefs from the impacts of climate change, new research finds. The study, by scientists at the National Center for Atmospheric Research (NCAR) and Australian Institute of Marine Science (AIMS), finds evidence that an ocean "thermostat" appears to be helping to regulate sea-surface temperatures in a biologically diverse region of the western Pacific.
Coral reefs will be permanently damaged without urgent action
Coral reefs could be damaged beyond repair, unless we change the way we manage the marine environment. New research by the Universities of Exeter and California Davis, published today in
Nature, shows how damaged Caribbean reefs will continue to decline over the next 50 years.
Why do so many species live in tropical forests and coral reefs?
The latest development in a major debate over a controversial hypothesis of biodiversity and species abundance is the subject of a paper to be published in the 1 November 2007 issue of the journal
Nature.
Regardless of global warming, rising CO2 levels threaten marine life
Like a piece of chalk dissolving in vinegar, marine life with hard shells is in danger of being dissolved by increasing acidity in the oceans.
Stormy days ahead for coral reefs
The increasing violence of storms under global climate change will have major effects on coral reefs – and has important implications for their future management.
Coral reefs are increasingly vulnerable to angry oceans
Size and shape may predict the survival of corals around the world when the weather churns the oceans in the years to come, according to a new model that relies on engineering principles.
Ocean acidification threatens cold-water coral ecosystems
Corals don't only occur in warm, sun-drenched, tropical seas; some species are found at depths of three miles or more in cold, dark waters throughout the world's oceans. Some cold-water coral reefs are home to more than 1,300 species of animals, a diversity rivaling some better known tropical coral reefs. Until now, scientists believed bottom trawling – a commercial fishing method in which vessels drag large, heavily weighted nets across the bottom – to be the greatest threat to cold-water corals. Now, however, a new study published in
Frontiers in Ecology and the Environment suggests that human activities could be threatening cold water reefs in another way.