A menagerie under the sea

A 10-year ‘census’ of the world’s oceans has brought over a thousand previously unknown species to light, with hints that there are many more.

sea creature 311 (photo credit: courtesy)
sea creature 311
(photo credit: courtesy)
God told Adam in the Garden of Eden to name all the fowl of the air and beasts of the field – but not the fishes, which he couldn’t see. That was left to the just-completed, decade-long first Census of Marine Life, in which 2,700 researchers from more than 80 countries – including Israel – participated.
The $650 million census spanned oceans from the North Pole to Antarctica and smaller seas such as our own Mediterranean, from the surfaces to the depths. It used divers, submersible vehicles, nets, sonar, electronic and acoustic tagging, genetic identification, listening posts and communications satellites to count some 250,000 species, including 1,200 newly discovered ones, from microscopic to large mammals. They also took 5,000 specimens in glass jars awaiting taxonomic description.
The researchers discovered cold-water corals extending off Mauritania in North Africa for over 400 kilometers and half a kilometer deep that comprised one of the world’s longest reefs. They tested a Caribbean clam species found to have thrived for at least 65 million years even though it had been thought extinct in the early 1800s. And off the coast of Chile are newly discovered microbial mats covering an area the size of Greece.
But it is only the beginning, as according to Jesse Ausubel – a co-founder of the global project who works for Rockefeller University and the Alfred P. Sloan Foundation that helped fund the census – an estimated one billion marine species actually exist.
BUT THE census not only counted the known species and discovered new ones; it also assessed the movements of species and – using historical databases – learned whether they have grown increased or are disappearing due to environmental factors.
A vast amount of information, videos and photos is available at its official Web site at www.coml.org.
Ausubel and Prof. Roberto Danovaro of the Polytechnic University of Marché (who focused on the Mediterranean) came to Israel recently to discuss the census and brief marine scientists at the Israel Academy of Sciences and Humanities in Jerusalem.
Among the local experts who took part in the census were Prof. Yossi Loya, a marine ecologist at Tel Aviv University’s zoology department and a member of the prestigious academy; Prof. Alex Keynan, an academy senior adviser who was the director of the Biological Institute in Nes Ziona in the 1950s and 1960s; Aahron Kaplan of the Eilat InterUniversity Marine Station; Ruthy Gertwagen of the University of Haifa; and Barak Herut, director-general of Haifa’s Oceanographic and Limnological Research Institute.
The all-day session discussing the findings and impact of the census was chaired by academy president Prof. Ruth Arnon.
KEYNAN TOLD the audience that Ausubel, with whom he has cooperated for 20 years, was the “first scientist to identify the phenomenon of global warming” and the man in charge of many ambitious marine study projects.
The New York expert noted that 70 percent of the Earth’s surface is covered by water; when continents are left black on a world map and the water given color, it is an unusual image indeed.
“The oceans are getting crowded and being used more, even though much remains unexplored. The number of large ships weighing over 100 gross tons has tripled since 1960,” he said.
“There are oil drillers, fishing trawlers, wind propellers to produce electric power and undersea wave machines. Ships travel such a large variety of routes that a depiction of them looks like a railroad map. Undersea telecommunications cables have been laid everywhere.
“There are offshore gas and oil fields in the Mediterranean, in the Gulf of Mexico, the North Sea, off Indonesia and in other locations.” Ausubel added that there has always been natural noise in the seas from underground earthquakes and the presence of whales and other creatures. But with shipping and other human interventions, the level of noise now doubles every decade and affects marine creatures. “Soon, there will be more human noise in the oceans than natural noise.”
COMPARING THE new data on marine species’ numbers, habitats and behaviors with those obtained from documents going back millennia – Greek philosopher Aristotle in the Fourth Century BCE identified crustaceans, echinoderms, mollusks and fish, and is often referred to as the father of marine biology – has now produced much information on changes, said Ausubel. During the project, participants have written many books, some of them put online. The census also produced a documentary film titled Oceans that has had $83 million in box office income so far, making it the fourth most successful documentary ever.
“The public took huge interest in the discoveries,” Ausubel said. Even sculptures were made based on the images, and songs were written about the creatures.
“There are also thousands of new technical papers. We looked at the diversity, kinds, distribution and abundance of marine creatures and where they travel, and we found that life in the oceans is richer than we imagined. The species are more connected and more scattered since earlier in human history,” he said. But many of the larger species are endangered compared to the smaller and microscopic species. Certain kinds of fish have declined in number by 90%. There is clearly a decline in the abundance of many species; it is very worrisome and saddening. But at the same time, seals and some whales, as well as sea birds, have recovered a lot. Chinese researchers found a lot of jellyfish species.”
According to Ausubel, new habitats are created even when a whale dies and sinks to the sea floor.
“A whole community can form around it. Even an empty dollhouse suspended under the surface can, over time, develop into a home for a variety of marine species,” he noted.
“Mud volcanoes near Spain and Portugal have produced new varieties of creatures.” One creature with rasta-like hair was named for the late reggae singer Bob Marley, while a new deepwater lobster discovered by Ausubel himself in 2007 in the Philippine Sea was called Dinochelus ausubeli; “my mother had a T-shirt with its image on it.”
The scientists discovered sea worms in the Gulf of Mexico with a lifespan of 500 to 600 years.
“Israelis have discovered plenty of worms that can actually find oil,” Ausubel said in his lecture.
“We prepared maps and found that many creatures lived where the Gulf of Mexico oil spill took place. Comparisons can be made of before and after.”
There are also “alien species” that, when geographical changes occurred, arrived in oceans and seas where they were not native. “The digging of the Suez Canal made the Mediterranean Sea the capital of 800 alien species. Some animals such as southern elephant seals and bluefin tuna swim great distances and are very cosmopolitan,” said Ausubel.
“Some are making incredible journeys – both vertical and horizontal. There are shrimp that can climb 400 meters up and down, as if they were on the Eiffel Tower.”
Census scientists developed ways to use graphic images to depict characteristics of species. For example, “hot spots” containing a large number of a certain certain type of creature; on a map, they appear as squares of a certain color.
Many creatures underwent analysis of their mitochondrial DNA, with each getting a barcode.
Ausubel noted that high school pupils in New York “bought a lot of sushi, extracted DNA and then persuaded scientists to identify the types of fish. It turned out that half of the sushi sold in NY is mislabelled. Cheap tilapia was presented as pricey albacore tuna.”
The Italian researcher Danovaro said that the Mediterranean Sea will not become more salty due to the proliferation of desalination plants that leave salt residue behind.
Instead, the melting of Arctic glaciers due to global warming will make the Mediterranean and oceans less saline, he suggested.
Danovaro, on his first visit to Israel, said the Israeli scientists had been very valuable to the project. Although the body of water on Israel’s west coast comprises only 0.8%of the world’s seas, it contains 6% of its marine life, said Danovaro.
But larger species such as sharks have been nearly wiped out by pollution, fishing and other causes, allowing smaller creatures, such as nematode worms, to thrive.
At the beginning of the census, Danovaro discovered a multi-celled sea creature near Crete that was the first known to live in an environment totally lacking oxygen. It is found in salt pockets at a depth of 3.5 kilometers – a very hostile environment, and as salty as the Dead Sea. It receives its energy, he said, by bonding with sulfates and sulfides in the water.
He worked with a team of researchers to retreive sediment samples from a deep salty basin that lacked oxygen bubbles in the water.
He studied them for signs of life.
“These extreme envirionments have been thought to be exclusively inhabited by viruses, bacteria and archaea.
The bodies of multicellular animals were previously discovered, but were thought to have sunk there from upper – oxygenated – waters. Our results indicate that the animals we recovered were alive. Some, in fact, also contained eggs.”
The creatures his team found were new members of the group Loricifera that were active and apparently reproducing despite a complete absense of oxygen. After Danovaro’s discovery, it is believed that more like it will be found.
The eastern Mediterranean is considerably warmer than the waters at the other end, near Spain and Portugal, said Danovaro, thus very different species live in each spot.
“But some important species have decreased so much that they don’t have an ecological role anymore. This is a threat to biodiversity, with more pollution, acidification and temperature changes affecting species.
“But at least the marine life maps of the Mediterranean are much better now than they were before.”