Nova: "Deep Sea Invasion"
Deep Sea Invasion
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PBS Airdate: April 1, 2003
[link|http://www.pbs.org/wgbh/nova/algae/| Go to the companion Web site]
NARRATOR: In the warm waters of San Diego, a team of marine biologists sets out on a routine dive. They're surveying the native eelgrass in this coastal lagoon.
In the beginning, everything seemed normal in this ocean paradise, where surfers ride the waves, and the lagoons are perfect for water sports. But below the surface trouble was brewing. The dive team moved slowly along the bottom. It was hard to see in the murky water. Then suddenly, they came face to face with an alien monster.
RACHEL WOODFIELD: You could just tell as you came up to it, there was trouble. It has a real insidious sort of creepy nature, as if it's some sort of blob that's taking over at the bottom.
GREIG PETERS (California Regional Water Quality Control): It's like out of a horror movie, but it's real.
NARRATOR: This is the alien, a seaweed called Caulerpa taxifolia. All seaweeds are algae, but this one is extraordinary. Caulerpa taxifolia is perhaps the largest single-celled organism in the world. One plant can grow nine feet long, and it spreads uncontrollably, turning lush marine landscapes like this into acres of green weed, an Astroturf\ufffd-like carpet and nothing more.
It was a scientific horror story. California had been invaded by a super algae that could overtake the Pacific Coast, and no one knew how to stop it.
But one man, 6,000 miles away, was all too familiar with this green monster. French seaweed expert, Alexandre Meinesz, had confronted Caulerpa taxifolia before. He found a patch of it a dozen years ago in the Mediterranean Sea and immediately sounded an alarm, but nobody listened.
ALEXANDRE MEINESZ (University of Nice, Sophia Antipolis): The authorities didn't want to know about the problem. We lost precious time when the algae could have been contained or maybe even eradicated.
NARRATOR: Today, about 40,000 acres of Mediterranean coastline is clogged with Caulerpa, and many scientists believe this beautiful sea is lost. Is America next? What can be done to stop this Deep Sea Invasion?
[...]
NARRATOR: This is Caulerpa taxifolia, a seaweed. And it's the most threatening underwater plant on earth. It can grow anywhere, at the astounding rate of one inch a day, pushing out everything in its path. Getting rid of it, if that's even possible, would require an all-out war, a biological battle between a weed and the scientists who understand the danger.
When Caulerpa taxifolia was discovered in San Diego, no one here had ever seen it before.
RACHEL WOODFIELD: We all knew when we saw it that it definitely wasn't something native. When I finally found a photo and the picture downloaded onto my computer, there was just a sinking feeling in my stomach.
NARRATOR: Within days, the infested lagoon was cordoned off like a crime scene, banned from human use and guarded by the police. Everyone now realized what could happen if they didn't act fast.
ROBERT HOFFMAN (National Marine Fisheries Service): We're assuming the worst case scenario: that if we don't control it, it's going to completely overtake this lagoon. And if we're wrong, I'd rather be wrong, over estimating the impact than underestimating it.
NARRATOR: The impact of alien species has been underestimated before. Africanized bees have killed more than a thousand people from Brazil to the United States, and now they threaten the American honey industry. With no natural predators, European gypsy moths have destroyed oak forests from Maine to the mid-west.
Today, thousands of alien plant, animal and insect species have invaded this country, costing hundreds of millions of dollars to control. But this seaweed may pose the worst threat of all.
Caulerpa taxifolia has already reshaped the Mediterranean Sea, mainly because no one listened to the one man who recognized the threat back in 1989. It all began here off the coast of Monaco.
[. . .]
One day, French marine biologist Alexandre Meinesz went diving in the Mediterranean. Meinesz is an expert on the marine life of the Mediterranean. He knew that among the dozens of plants that live here, one is fundamental to the sea's ecosystem. It normally covers large areas of the seabed. It's a dark, gray-green sea grass called "possidonia." Possidonia is a plant that provides food and shelter for a huge variety of fish and other sea creatures.
But that day, as Alexandre Meinesz dived, nothing was as he expected it to be.
ALEXANDRE MEINESZ: The water was very clear, the sun was shining, and visibility was good, and I saw straight away that the seabed was bright green. I said to myself, "This isn't possible. There shouldn't be any brilliant green seaweed here."
NARRATOR: Where Meinesz had expected to find the usual variety of Mediterranean sea life, all he could see for hundreds of yards was a dense, bright green mat of weed he'd never seen before. Everything was smothered in it.
ALEXANDRE MEINESZ: I went deeper, to the bottom. It was still there. Then I went to the west and to the east, and it was still there as well. I was really astonished at the size and extent of the algae. It struck me as being supernatural.
NARRATOR: As he studied the extraordinary new plant, he realized it was a giant variant of a tropical seaweed, or algae, called Caulerpa taxifolia. Yet how could a tropical plant survive in the colder waters of the Mediterranean?
ALEXANDRE MEINESZ: I didn't understand how such a vigorous tropical algae could withstand the cold and survive\ufffdand not just that, could spread. That was something extraordinary.
NARRATOR: He decided to find out what was going on. Back in the laboratory, he compared Caulerpa taxifolia with other specimens of the same family from around the world.
[Quite More ...]
In brief: and following the utterly-French, and Bush-like intransigence of the head of the marine biology HQ of Monaco, the apparent source of the first 'spot' discovered! - described above:
The alien traces back to a Special variety of Caulerpa taxifolia popular in home, other aquaria. Speculation is that this is a mutation of the species, perhaps brought about by the peculiar conditions in these tiny aquaria, the UV lights and chemicals often found associated. It seems that very few 'colorful' algae will grow in these aquaria - hencce the worldwide popularity of This one.
Simply: the dumping of any small strand of this Alien-IV? is sufficient to create a bloom. Its asexual reproduction is the clue; it's more akin to cloning (biologist's simile). The chain of evidence to this source is established via DNA analysis: this and Only this variety matches the Mediterranean (and then elsewhere) samples. [This was established - before the Nova prod. of '03.]
Doesn't Need 'tropical' waters because of the genetic mod. Food chain: read the transcript. Is this the Real-beginning of all those sci-fi flic plots?
Note the eradication methods attempted thus far, also - considering that Nova has yet to be accused of hysterical outbursts
[. . .]
They also considered something more drastic: pumping copper sulfate into the water. It would kill every living thing and close the lagoon for two years. While copper sulfate may well prevent the weed from moving into the open ocean and threatening the fishing industry, for many Australians, it's just too controversial. So no decision has been made. For now, they're trying to stem the spread by pulling the taxifolia out by hand.
Fifteen years after it was first discovered, Caulerpa taxifolia now grows in nine countries on four continents. The problem is entirely manmade. Today, millions of tropical fish hobbyists still decorate their aquariums with this brightly colored but dangerous plant. Improper disposal of even a tiny fragment of Caulerpa taxifolia can start the next infestation as this green monster continues to spread throughout the world's oceans.
It's not just this invasive plant that we need to worry about, other alien species are attacking habitats in waters and on land around the world.
{sheesh} as.. if.. a Loony-cabal with nukes, a $-rapacity unmatched by Croesus and a desire for Rapturin-Out.. weren't Enough ?!
