Earthwatch Radio through Seagrant Institute-University of Wisconsin, Madison, August 28th, 2006
Drama of the Deep (radio script based on interview with Marsh Youngbluth)
Some of the biggest predators in the deep ocean are large colonies of jellyfish. They sweep the water with "a curtain of death" and disintegrate when anyone tries to take their picture.
By Emily Laughnan
Some jellyfish that live in the deep ocean sweep the water with networks of stinging tentacles to capture food. These gelatinous critters can be as long as a whale but they break into pieces when they're exposed to bright lights. Scientists say these animals are an important part of deep-sea ecosystems but they're hard to study because they're so fragile.
Marsh Youngbluth is a biologist with the Harbor Branch Oceanographic Institution in Fort Pierce, Florida. He's been studying marine life for almost 40 years, and one of his subjects is a jellyfish known as Apolemia uvaria. Youngbluth says a single colony of these creatures can be 50 feet long, and its tentacles reach out as far as 15 feet.
"These animals operate by dangling tentacles in the water column. Actually, it's like a curtain of death out there."
Cells at the end of these tentacles fire little darts into fish and other marine creatures. Once a creature is impaled, the jellyfish colony reels it in and consumes it. Youngbluth says these creatures have a major impact on marine communities by eating the eggs and larvae of fish. But deep-water jellyfish can be tough to monitor. Some of them shrink or even self destruct under bright lights so it's hard to get pictures of them.
Youngbluth says individual colonies of these jellyfish might be fragile, but the species themselves have been around for a very long time.
"The jellyfish -- or the soft bodied zooplankton -- have been around for millions and millions of years, before the fishes came."
Youngbluth is currently leading an investigation of jellies in the Gulf of Maine and in deepwater canyons along the southern edge of Georges Bank.
Script for Monday, August 28, 2006
Originally aired March 2005
Marsh Youngbluth portrait on Science of the Deep section of The Science Channel
Siphonophore Image Catalogue at site of Image Quest Marine