THE GREAT BARRIER REEF is one of the planet’s most famous natural wonders, stretching across 348,000sq.km and comprised of more than 2900 separate reefs. But disturbing new research reveals it has lost half its coral cover since 1985.
The study from the Australian Institute of Marine Science (AIMS), published today in the US journal theProceedings of the National Academy of Sciences, provides a dim view of the reef’s future.
“Coral cover on the GBR is consistently declining, and without intervention, it will likely fall to 5 to 10 per cent within the next 10 years,” say the authors of the report. “Without intervention, the GBR may lose the biodiversity and ecological integrity for which it was listed as a World Heritage Area.”
Whale Shark
Photograph by Brian Skerry
The sweeping color of sea and sky, blue is a common thread in nature, seen in the cerulean of a whale shark (pictured here), the indigo of a stormy night, and the cobalt of a peacock’s feathers. Over the centuries, the hue has come to represent calm, cold, mysticism, and sadness.
Between 700,000 and one million species live in the world’s oceans, according to a thorough new analysis, which also estimated that between one-third and two-thirds of those species have yet to be named and described.
The new numbers are far smaller than previous estimates, which had put the tally of marine species as high as 10 million or more. By coming up with a more accurate picture of what we know and what we don’t yet know about marine life, the study should help scientists better focus conservation efforts where they’re needed most.
“You can only love something if you know it,” says Ward Appeltans, a marine biologist at the Intergovernmental Oceanographic Commission of UNESCO in Oostende, Belgium. “We will not save the world with this result, but we may start understanding it better.”
The new findings also open up the possibility that we may eventually be able to identify just about every creature living in the sea.
“It may not be mission impossible to describe all the marine species in the ocean,” Appeltans says. “We are describing 2000 new marine species every year. If we can keep that momentum, we can start knowing exactly what’s living on our planet.”
Necklace Sea Star
Photograph by Wolcott Henry
A necklace sea star nestles among the C-shaped emerald tentacles of anchor coral in the western Pacific Ocean.
Bluebottle - Physalia physalis
Commonly known as the bluebottle because of the indigo balloon that carries them across the ocean, the Portuguese man-of-war are known for being some of the peskiest stingers in Australia. The individual ‘zooids’ are a part of a large colony that makes up one gigantic organism. Each individual has an allocated task for survival and collectively the full colony floats around the ocean, carried by the wind. Like ants, the venom is painful but not usually fatal, unless a severe allergic reaction occurs. Their stinging tails are roughly 15cm long and they cause approximately 10,000 stings every summer.
Photo Credit: Getty Images
Elephant Seal (Mirounga leonina), Right Whale Bay
Another common local: South Georgia hosts the largest subpopulation of southern elephant seals in the South Atlantic, with more than 400,000 individuals, including approximately 113,000 breeding females, from a total world-wide population that was estimated to be between 664,000 and 740,000 in the mid-90s. Colonies on South Georgia are thought to be stable or growing, while those in the Southern Indian and Pacific Oceans have decreased by up to 50%.
Photo Credit: Bernat Garrigos
A NEW METHOD for controlling outbreaks of crown-of-thorns starfish is providing new hope for the future of the Great Barrier Reef.
Marine scientists have discovered that injecting a protein mixture into the coral-feeding starfish (Acanthaster planci) induces disease, killing the pest within 24 hours. If deemed ecologically safe, the method could provide a fast, cost-effective means of controlling the invader, with significant benefits for the iconic reef.
Crown-of-thorns starfish (COTS) outbreaks are one of the leading causes of coral death on the Great Barrier Reef. Since 1985, the reef has lost more than half its coral cover and COTS are responsible for 42 per cent of that loss.
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A newfound ability of reef fish to adapt to shifting conditions over the course of two generations indicates they might be less vulnerable to climate change than previous research has suggested. In a new study, young anemonefish (Amphiprion melanopus) exposed to elevated carbon dioxide levels and warmer water grew slowly, needed extra energy to perform normal bodily functions and died at higher rates. But they showed no adverse impacts if their parents had lived under the same conditions prior to breeding. Recent research shows that young fish are particularly vulnerable to the decreases in water pH that are expected to occur over the next century as elevated CO2 levels change the chemistry of the oceans . Zoologist Gabrielle Miller and her colleagues at James Cook University in Townsend, Australia, wanted to know what might happen if parents as well as hatchlings were exposed to such conditions. Read More
Mark Gray’s photo of Hardy Reef, on the Great Barrier Reef, Queensland
