October 8, 2009—Giant, jelly-like sheets of dead and living organic matter, known as marine mucilages, are spreading throughout the Mediterranean. The blobs may smother marine life and carry diseases dangerous to humans. (Read the full story, and see pictures.)
© 2009 National Geographic; Video Courtesy Piero Mescalchin
It resembles the blob from science fiction stories.
But its very real.
These jello-like sheets of disease-carrying mucus are spreading across portions of the Mediterranean and Adriatic Sea, where this video was taken.
This stringy mess is known as marine mucilage.
Theyre visible on the surface of the water, as wellcreating a sudsy look in the sea.
Its not one organism, but a congregation of organic matter joined together. The mucilage begins as a cluster of mostly microscopic dead and living matter, and over time, picks up others looking for food or safety.
Only some of the animals are visible to the human eye, such as small shrimp and crustaceans.
These blobs have been known to exist at least since 1729, but a recent study found a link between mucilage outbreaks and warmer sea temperatures.
Study leader Roberto Danovaro, from the Polytechnic University of Marche in Italy, says theres concern because the blobs attract bacteria and viruses, including e-coli.
That would make the blobs harmful to swimmers, and an e-coli presence can force closure of beaches.
Danovaro says the mucilages are largest in the summer months.
His study found that the number of mucilage outbreaks increased almost exponentially in the last 20 years in the Mediterranean. He cautions that its a good example of what can happen if climate warming continues.
The bacteria can be deadly to fish and other living organisms in the water. And the noxious mass also traps animals, coating their gills and suffocating them.
The biggest blobs can sink to the sea floor, acting like a blanket, and smothering life at the bottom.