Caribbean reefs face severe summer threat

From an article by Andrew C. Revkin on The New York Times' Dot Earth:

Coral reefs in a broad swath of the Caribbean face a substantial risk of severe bleaching and die-offs through October, the National Oceanic and Atmospheric Administration said on Wednesday [July 22] in its latest Coral Reef Watch report.

Similar conditions may develop in the southern Gulf of Mexico and central Pacific, the agency said. But the report said the widest area of high risk was in the southern Caribbean, from Nicaragua’s east coast across the south coasts of Haiti and the Dominican Republic and from Puerto Rico south along the Lesser Antilles. Rising ocean temperatures are contributing to the risk, the report said, noting that the National Climatic Data Center reported that in June the world’s ocean surface temperature was the warmest on record.

From the report:
Scientists are concerned that bleaching may reach the same levels or exceed those recorded in 2005, the worst coral bleaching and disease year in Caribbean history. In parts of the eastern Caribbean, as much as 90 percent of corals bleached and over half of those died during that event.

See an ealier report here.

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Algae has eyes!

From an article by Christine Dell'Amore on National Geographic News:

The single-celled algae that set up house inside hard corals and give reefs their vibrant colors may be able to see, a new study says.

The algae—called zooxanthellae—have mysterious crystal-like deposits, which were found to be made of uric acid, a common element in light-reflecting structures in insect and animal eyes.

The substance in the algae had been previously misidentified as calcium oxalate, which is often found in plants, the researchers say.

The algae's crystal clusters strongly reflected light in lab experiments, suggesting that "this is really a functional eye," study co-author Kazuhiko Koike, of Japan's Hiroshima University, said in an email.

Each of the single-celled orgamisms also contains a photoreceptor molecule, which creates an "eyespot."

Eyespots are light-sensitive patches that allow simple organisms, such as jellyfish and some other algae, to sense their environments.

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Weekly Internet video broadcasts on ocean issues

From an e-mail sent by Ocean Champions:

. . . be sure to join us today [July 29, 2009] for Rob Moir's Environmental Dialogues as Ocean Champions' Mike Dunmyer will be discussing Toxic Tides and other priority ocean issues with Congressman Brian Baird (D-WA). Congressman Baird Chairs the Science and Technology Committee's Subcommittee on Energy and Environment, and is a knowledgeable leader on ocean issues in Congress.

Rob Moir's Environmental Dialogues air every Wednesday from noon to 1:00 PM EST (9:00 AM to 10:00 AM PST). These lively dialogues and revealing narratives inquire into how individuals are overcoming the obstacles of turning forlorn hope into effective actions for oceans, rivers, watersheds, wildlife and ecosystems. Today's show includes the Massachusetts Ocean Program and Seaweed Rebel David Helvarg (Blue Frontier).

In addition, at roughly 12:45 EST each week, Ocean Champions talks with Dr. Moir about breaking ocean news including happenings in Washington DC.

You can tune in via Internet radio at:
http://www.modavox.com/voiceamerica/vshow.aspx?sid=1570

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Smaller, more concentrated 'dead zone' in the Gulf of Mexico

From an article on Underwater Times News Service:

WASHINGTON, D.C. -- NOAA-supported scientists, led by Nancy Rabalais, Ph.D., from the Louisiana Universities Marine Consortium (LUMCON), found the size of this year's Gulf of Mexico dead zone to be smaller than forecasted, measuring 3,000 square miles. However the dead zone, which is usually limited to water just above the sea floor, was severe where it did occur, extending closer to the water surface then in most years.

Earlier this summer, NOAA-sponsored forecast models developed by R. Eugene Turner, Ph. D. of Louisiana State University and Donald Scavia, Ph.D. of the University of Michigan, predicted a larger than normal dead zone area of between 7,450 – 8,456 square miles. The forecast was driven primarily by the high nitrate loads and high freshwater flows from the Mississippi and Atchafalaya rivers in spring 2009 as measured by the U.S. Geological Survey.

Rabalais believes the smaller than expected dead zone is due to unusual weather patterns that re-oxygenated the waters, among other factors.

"The winds and waves were high in the area to the west of the Atchafalaya River delta and likely mixed oxygen into these shallower waters prior to the cruise, thus reducing the area of the zone in that region," said Rabalais. "The variability we see within each summer highlights the continuing need for multiple surveys to measure the size of the dead zone in a more systematic fashion."

"The results of the 2009 cruise at first glance are hopeful, but the smaller than expected area of hypoxia appears to be related to short-term weather patterns before measurements were taken, not a reduction in the underlying cause, excessive nutrient runoff." said Robert Magnien, PhD., director of NOAA's Center for Sponsored Coastal Ocean Research. "The smaller area measured by this one cruise, therefore, does not represent a trend and in no way diminishes the need for a harder look at efforts to reduce nutrient runoff."


Runoff also presents a problem along the Mexican coastline.

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Oceans hold the solution to Earth's woes

From a commentary in the Miami Herald by Sam Waterston, actor and board member for global ocean conservation group Oceana:

They've been a highway for goods and people, connecting us to the world, and a barrier against foreign invasion, protecting us from the world; a source of food and wealth, going back to our earliest beginnings, when whale oil lit our houses and when cod were so plentiful in New England that huge specimens were commonly stacked like cordwood on New England docks and wharves and still there were so many that you could walk on their backs across some harbors.

Until the recent unrelenting hammering by our technologically impressive, very efficient, very destructive fishing fleets, the seas have been an inexhaustible cornucopia of sea life for our sustenance, delight and wonder. For just as long, they've been an uncomplaining dump. They've absorbed our waste -- trash, sewage and, from manufacturing and power generation, nuclear waste and oil spills.

For the last 250 years, oceans have also been a great sink, absorbing 30 percent of the carbon dioxide we put into the atmosphere through the burning of fossil fuels and deforestation, moderating and masking its global impact. They take in 11 billion metric tons of carbon dioxide per year. Each year, the amount we release grows another 3 percent.

Early-warning system
And still the oceans serve us. In fact, they're performing double service. First, they are giving us early warning, telling us in plain language, the certain consequences of continuing to consume as we are. Second, they're offering us a solution to the problem that has brought us to this dangerous moment, namely humanity's vast appetite for energy. So what happens to the carbon dioxide absorbed by the seas? It combines with seawater to create carbonic acid, changing the acidity of that vast solution and reducing the amount of available carbonate. And that is serious mischief for all kinds of sea life, from corals and pteropods, continuing on through shellfish, clams, oysters, lobsters, mussels and so on, that need carbonate to make the structures that support them.

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Study shows ocean health plays vital role in coral reef recovery

Jessica Carilli (left) collects a core sample using an air-powered drill system. Photo: Scripps Institution of Oceanography, UC San Diego

From a news release issued by Scripps Institution of Oceanography:

The new research study led by scientists at Scripps Institution of Oceanography at UC San Diego suggests that by improving overall ocean health, corals are better able to recover from bleaching events, which occur when rising sea temperatures force corals to expel their symbiotic algae, known as zooxanthellae. Coral bleaching is a phenomenon that is expected to increase in frequency as global climate change increases ocean temperatures worldwide.

The new findings, published in the July 22 issue of the journal PLoS ONE, show that following a major bleaching event Mountainous star coral (Montastraea faveolata) on various reefs in Honduras and Belize was able to recover and grow normally within two to three years when the surrounding waters and reef were relatively healthy. In comparison, those corals living with excessive local impacts, such as pollution, were not able to fully recover 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, Scripps graduate student and lead author on the study. "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."

Carilli and colleagues analyzed 92 coral cores collected from four reef sites off the coast of Honduras and Belize. The cores were collected from reefs with different degrees of local stress from pollution, overfishing and sediment and nutrient run off from land. By using x-rays, the researchers were able to examine the coral's annual growth rate records since 1950, including the time before and after a major bleaching event in 1998.

"It is clear that Mesoamerican corals really fell off a cliff in 1998 -- nearly everybody suffered mass bleaching," said Dick Norris, Scripps professor of paleooceanography and co-author of the study. "There are no pristine reefs in the region, but the ones in the best shape clearly are more resilient than those that are long-suffering. It shows that a little improvement in growing conditions goes a long way in recovering coral health."

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Turtle rescued after swallowing balloon; 'It's extremely common'

From an article on Underwater Times News Service:

SARASOTA, Florida -- An endangered Kemp's ridley sea turtle (Lepidochelys kempii) has been brought to Mote Marine Laboratory's Sea Turtle Hospital after it swallowed a balloon - an episode that we hope will remind residents and visitors to stow their trash carefully.

The 3.3-pound young turtle with a carapace 8.7 inches long washed up on a sandbar near the south end of Lido Key on Tuesday, July 14, with what appeared to be fishing line hanging from its mouth. Concerned swimmers called Mote biologists, who brought the Kemp's ridley to Mote's Sea Turtle Hospital.

Before removing the pink line, which had scraped skin from the turtle's face, Mote staff used radiographs to verify that the turtle had not swallowed a fishing hook. Instead, they found remnants of a black balloon.

"Balloons can look like jellyfish or squid - things sea turtles like to eat," said Senior Biologist Kristen Mazzarella of Mote's Sea Turtle Conservation and Research Program. "It's extremely common to find sea turtles that have swallowed balloons, fishing hooks, monofilament lines and other dangerous objects."

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