The seafloor at Viosca Knoll
Credit: Harbor Branch/E. Widder
A Harbor Branch-led team of scientists has just returned from a wildly successful exploratory expedition to the Gulf of Mexico called Operation Deep Scope that was funded by the NOAA Office of Ocean Exploration. The group had to run 100 miles off its scheduled course to avoid Tropical Storm Bonnie, and dodged a misguided swordfish and a curious sixgill shark, but scored a number of important accomplishments.
The research team collected strong proof-of-concept for a new unobtrusive deep-sea camera system called Eye-in-the-Sea in the form of spectacular deep-sea predator footage, and data to support a new theory about how some animals may use polarized light to find prey. The scientists also discovered new phenomena such as the world's first known fluorescent shark and fluorescence from methane hydrates, which could lead to a new detection technique for this potential future energy source.
"This has been exploration in its purest form, something that is all too rare," says expedition co-leader Dr. Edie Widder, head of Harbor Branch's Biophotonics Center. "To say that this cruise was a success would be an understatement," she says, "We are returning with an embarrassment of riches"
For more information about the expedition and its goals, please see: www.eurekalert.org/pub_releases/2004-08/hboi-rbd080204.php
The expedition took place aboard Harbor Branch's Seward Johnson II research vessel and Johnson-Sea-Link I submersible. The research component ran from Aug. 7-18th, and the ship returns to port Aug. 21.
KEY EXPEDITION HIGHLIGHTS:
Images from the Eye-in-the-Sea of a large squid and sixgill shark
Credit: Harbor Branch/ E. Widder
1) The prototype Eye-in-the-Sea proved itself beyond all expectations collecting unprecedented video glimpses of deep-sea life. The system captured footage of a huge, as yet unidentified, squid, a massive sixgill shark, and other animals. A jellyfish lure designed to mimic bioluminescent displays made by deep-sea animals appears in some clips to have attracted animals to it, suggesting that the system could be an important tool for studying the various uses of bioluminescence in the deep sea, which is one of its main purposes. (For more information about the system please see: http://www.hboi.edu/news/press/sept0203.html)
Dr. Widder and her team have already applied for funding from the National Science Foundation to build a more elaborate version of the Eye-in-the-Sea that could be deployed by submersible or integrated into underwater observatories at places such as Monterey Canyon off California. If placed at an observatory he new system would be connected to shore via fiber optic cable allowing control of camera direction and other parameters, constant power supply, and a steady flow of deep-sea images for extended periods of time. This could enable scientists to finally begin to clearly understand what life is like in the deep sea.
2) Dr. Charles Mazel, of Physical Sciences, Inc., in Andover, Mass., discovered the world's first fluorescent shark using special blue filters on the submersible lights to trigger fluorescence, and yellow filters that block out non-fluorescent reflected light to observe and video tape it. The team also collected a number of fluorescent animals such as crabs, corals, anemones, and fish that they will study in coming weeks to determine if the samples contain fluorescent proteins that might offer benefits for genomic and other biotechnology research.
KEY EXPEDITION HIGHLIGHTS:
A deep-sea anemone under fluorescent and natural lighting
Credit: C. Mazel
3) While searching for new fluorescent animals, Dr. Mike Matz, from the University of Florida, unexpectedly discovered that methane hydrates are brilliantly fluorescent. Methane hydrates are ice crystals that form under a narrow range of temperature and pressure conditions trapping they fossil fuel methane inside them. Hydrates are widespread throughout many deep-sea areas and some permafrost land areas as well. They are already being explored as a future energy source, and the knowledge that they fluoresce could lead to new detection techniques.
4) Divers working in open water near the surface gathered data that strongly supports a new theory put forth by Dr. Justin Marshall that some animals use polarized light to detect and prey on animals such as jellyfish and fish larvae whose transparency would otherwise render them invisible. Dr. Marshall took video at various depths and angles with polarized filters, then analyzed the footage to determine how much light in a given area is polarized. He measured values as high as 40%, suggesting at least the possibility that polarized light plays an important role. Study on the ship of various transparent creatures showed that some animals appearing transparent to human eyes stick out prominently under polarized filters. This combined with the polarization measurements lends strong support to Dr. Marshall's theory.
larvae-unpolarized.jpg (to the left) and larvae-polarized.jpg (to the right)
Non-polarized (L) and polarized (R) views of an eel larvae (leptocephalus)
5) Dr. Edith Widder discovered the first known bioluminescent anemone. She found that Venus flytrap anemones produce a bioluminescent slime, though its use by the animals is not yet clear.
6) The team had several incredible run-ins with large predators during submersible dives. At two separate locations, massive sixgill sharks were present long enough for extended views, and on one occasion a disoriented swordfish attacked the submersible, though it did not cause any damage. Each event was captured on video.
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