UniTEd

        The Great Barrier Reef hosts 5,000 types of mollusks, 1,800 species of fish, 125 types of sharks, and innumerable miniature organisms(each organism plays an important role in the ecosystem). The status though is more focused on the vast expanse of coral, from staghorn stalks and wave-smoothed plates to mitt-shaped boulders. The reef may degrade below a crucial threshold from which it cannot bounce back, even after conquering previous wars. There are more than 10,000 square miles of coral ribbons and isles waxing and waning for some 1,400 winding miles. That’s over too much square footage to be worried about... though it’s mostly our fault, so it’s our duty to redeem ourselves.

Coral polyps, the reef’s building blocks, are tiny colonial animals that house symbiotic algae in their cells. As those algae photosynthesize(using light to create energy) each polyp is fueled to secrete a “house” of calcium carbonate, or limestone. As one house tops another, the colony expands like a city; other marine life quickly grab on and spread, helping to cement all the pieces together. The Great Barrier Reef was manifested with coral polyps and with the reef continuously eroding, worn down by waves, ocean chemistry and organisms that eat limestone, it’s hard to survive. The perfect temperature, however, and currents for the reef enable plate corals to increase in diameter up to a foot a year. The vanishing act is far slower than the the constant building up. Still, as much as 90 percent of the rock eventually dissipates into the waters, forming sand.

The relatively quick shift in the world’s climate, scientists say, appear to be devastating for reefs and their inhabiters. In corals, warming temperatures and increased exposure to the sun’s ultraviolet rays lead to a stress response called bleaching. When the colorful algae in coral cells become toxic and are expelled, it transforms the host animals skeletal white. Fleshy seaweeds may then choke out the remains. Heat is also implicated in a 60-year decline in ocean phytoplankton(microscopic organism that gobble greenhouse gases, plus also feed directly or indirectly on every other living thing in the sea). A more immediate concern is massive flooding in Australia that earlier this year sent huge plumes of sediment and toxin-laden waters onto the reef of Queensland. 

Fears that with unprecedented CO2, sulfur and nitrogen emissions by human industry, much of the reef, adding to the increasing escape of methane(as a result of the Earth’s melting ice) will be bereft of life within 50 years. The reef bears a two-mile-long scar from a collision with a Chinese coral carrier in April of last year. Other ship groundings and occasional oil spills have marred the habitat. Sediment plumes from flooding and nutrients from agriculture and development also do very real damage to the ecosystem. And as if that were not enough to add to the excitement, Hawksbills turtles are illegally harvested for their shells and are declining globally. Some 3,000 rest along the Barrier Reef.
By Jennifer S. Holland(N.G./May 2011)

Necklace Sea Star. 

Sea Stars.

Submerged plane.