The Census of Marine Life, a global, decade-long effort to survey the oceans and their inhabitants, will conclude this October. But scientists presenting yesterday at a meeting of the American Association for the Advancement of Science in San Diego offered a sneak peak of what has come of the Census so far.
Anywhere and Everywhere
The wide-ranging research effort has uncovered more than 5,300 previously unknown marine animals in many of the harshest, most remote areas of the oceans. Researchers have mapped massive, deep-water coral reefs and traced the paths of many of the oceans' largest predators using high-tech tags, identifying crucial feeding grounds on the high seas. This information will help policymakers identify boundaries for marine protected areas that governments have committed to establishing by 2012. The researchers' findings also reveal declines in biodiversity in more acid waters and show that climate change is already having an impact on the oceans. In this photo, researchers use a remotely operated vehicle to measure the highest marine temperature ever recorded -- 407 degrees Celsius (765 degrees Fahrenheit).
The New Class
Among the new species found were squid, octopuses and jellyfish living at intermediate depths, discovered as part of the first intensive survey of the entire water column, rather than just the surface or the ocean floor, said Ron O'Dor of Dalhousie University in Halifax, Nova Scotia and senior scientist for the Census. Researchers also surveyed seamounts. "We think there are about 50,000 huge, underwater mountains of volcanic origin over one kilometer (0.6 miles) high," said Jason Hall-Spencer of the University of Plymouth in the UK. "We've only surveyed 100 of them in detail. Everywhere we've been we've uncovered new species." This marine sea spider is one of the many possible new species discovered by researchers.
Hall-Spencer's work has also revealed huge deep-water coral reefs, which researchers did not know existed, including a giant, 8,000-year-old reef in the Arctic ocean, which was 450 meters deep (1,476 feet), 35 kilometers (21.7 miles) long, and hundreds of meters high. This antipatharian coral, seen here surrounded by squat lobsters, is a new species discovered on the reef.
Meanwhile, at the opposite pole, the Antarctic's hostile surface belies the abundant undersea wildlife below. "Antarctica looks like this cold, harsh environment," said Huw Griffiths of the British Antarctic Survey. "But if you go beneath the ice, especially on the sea floor, there are more than 8,000 species, the majority of which are only found in Antarctica. It's kind of an amazing isolated place where different animals have evolved differently." Various Antarctic and deep sea octopuses appear in this image.
Sea spiders in the Antarctic, for instance, grow to the size of dinner plates -- far larger than the thumbnail-sized ones that live near Europe. So many new isopods -- small, flattened crustaceans with seven pairs of legs -- have been uncovered as part of the Antarctic Census of Marine Life, Griffiths said, that at this rate it would take 100 years to classify and name them all. And one fish found in Antarctica, pictured here, carries antifreeze in its blood to cope with below-freezing water temperatures. The fish also has no red blood cells, which would burst below freezing. Extra-cold water is also especially oxygen-rich, so the fish draws all of its oxygen from the water without the need for red blood cells.
Vision of the Future
Beyond revealing new species, the Census has also provided practical clues about the oceans' future and how best to manage them. The seamounts have given Hall-Spencer a preview of our changing oceans. At one site, an undersea vent spewing carbon dioxide creates an acidic environment that offers a look into what the future may hold as global carbon dioxide emissions drive acidification throughout the oceans. In this photo, a school of bluestripe snapper are seen near Christmas Island.
"I've been able to swim through a timeline into the future," Hall-Spencer said. "You can see which species can thrive and tolerate acidification." Invasive algae from Japan are doing well, he said, as are sea grasses, which are fertilized by CO2. "There is a 30 percent reduction in biodiversity when you get to pH 7.8, which is predicted by the end of this century," he said. "All of the calcifiers (organisms with hard outer skeletons or shells) are either dissolving or dead. Their skeletons are exposed to corrosive water." This "yeti crab" is a new species discovered in the South Pacific Ocean.
Deep water coral reefs are also poised to fall apart from acidification, Hall-Spencer said. The massive reef his team found lies just above the depth below which calcified shells can't form. As the ocean acidifies, this boundary is becoming shallower. "We've already seen a 30 percent increase in acidity since before fossil fuels were burned," he said. "It's likely that the reef will start to dissolve just as we've started to study it." Things are changing in Antarctica, too. "Already in the surface waters, we've seen changes that are linked to global change," said Griffiths.
From Top to Bottom
When sea ice melts in the spring, the breaking chunks act as a nursery ground for whales and seals. As the sea ice recedes, this nursery shrinks. In areas where sea ice is reduced, krill populations, part of the base of the food chain, have dwindled. This may have many trickle-down effects, including on the sea floor, where organisms rely on what falls from above. Understanding the location of diversity hotspots, breeding and feeding grounds, and other key sites -- the type of information revealed by the Census -- can help identify smart boundaries for marine protected areas. In this photo, a whale shark appears off the coast of Ningaloo Reef near western Australia.
Hall-Spencer and colleagues have worked with local fishermen, for example, to create a series of marine protected areas that enclose deep-water reefs. These areas will shield reefs from trawling damage and preserve the breeding and feeding ground that will sustain the commercial fishery. "Governments are committed to establishing networks of marine protected areas by 2012," said Kristina Gjerde, a policy advisor for the International Union for Conservation of Nature, based in Konstancin-Chylice, Poland. "We are trying to answer the question of how do you identify these protected areas given how little we know about the open ocean and the high seas. We now know much more than we did 10 years ago."