Revealing bizarre deep-sea secrets

August 06, 2004

PANAMA CITY, Fla.--On Saturday, Aug. 7, Harbor Branch marine biologists and others will set out from Panama City, Fla. on an expedition called Operation Deep Scope to study the fantastic life forms of four alien landscapes in the deep reaches of the Gulf of Mexico. The team will be using the most advanced array of imaging tools ever deployed in the deep sea with the goal of revealing never before seen animals, behaviors, and phenomena.

The expedition is funded by the National Oceanic and Atmospheric Administration's (NOAA) Office of Ocean Exploration, which was created to investigate the oceans for the purpose of discovery and the advancement of knowledge. NOAA is an agency of the U.S. Department of Commerce.

Deep Scope will take place aboard Harbor Branch's Seward Johnson II research vessel and the Johnson-Sea-Link I submersible, which is capable of diving to 3,000 feet. Besides Harbor Branch scientists, the expedition will include researchers from Duke University; the University of Queensland, Australia; the Whitney Lab of the University of Florida; the University of Ulm, Germany; and Physical Science, Inc., in Andover, Mass.

"This is the first time we've ever been able to assemble a team like this, with such a range of tools," says Dr. Edith Widder, expedition co-leader and head of Harbor Branch's Biophotonics Center, "Some of these areas have never been explored before and for many of the scientists, this expedition is a dream come true."



The explorations will begin at Desoto Canyon where the team will study unexplored deepwater pinnacles about 120 miles south of Pensacola that support a diverse range of animals. Next they will visit a spectacular deepwater coral reef at a site known as Viosca Knoll. The third site is a community of chemosynthetic clams and worms that rely on methane-eating bacteria for nutrition. The worms are plentiful around the seeps and attract a number of predators such as fish and deep-sea sharks. Finally, the group will travel to a bizarre site 150 miles southeast of New Orleans known as the Brine Pool. There, salt deposits in the seafloor dissolve to create water so dense that it forms a shallow lake 2,100 feet below the ocean's surface.

The expedition's main mission will be to discover new animals and new behaviors at these locations. To do that, the team will focus on observing and understanding the myriad uses of light in the dark reaches of the deep sea. More specifically, they will study the chemical-based bioluminescent light most deep-sea animals produce as well as fluorescent light, also given off by many marine animals. Other tasks will include measuring the amount and types of light found in the deep sea, as well as how the eyes of deep-sea animals allow them to see the faint light found in their dark home.

Scientists are confident that the deep sea still holds numerous secrets, such as the identities of creatures that have so far eluded attempts to see and study them because of severe limitations with conventional techniques. Submersibles and remotely operated vehicles can scare away most mobile life with their bright lights, loud noises, and strong electrical fields, while nets allow countless animals to swim away unseen and shred slower, softer animals beyond recognition.

"We're absolutely certain that we're still missing a great deal," says Dr. Widder, though conventional tools are important and have revealed much.

For this mission, the team will be using tools that avoid some conventional pitfalls. One key instrument will be the Eye-in-the-Sea, which was designed by Dr. Widder. This unique camera system will be deployed on the seafloor using the submersible and left for 24-hour or longer intervals to film animals and activities using very low levels of infrared light that deep-sea animals cannot see. This will allow the camera to capture natural behaviors and quite possibly footage of animals that have evaded scientists using other tools.

The system can be triggered to begin recording at programmed intervals to record animals attracted to bait or to an artificial lure designed to mimic the light given off by a common deep-sea jellyfish. (For more information about Eye-in-the-Sea and the jellyfish lure, please see: http://www.hboi.edu/news/press/sept0203.html).



Dr. Tammy Frank, the expedition's other co-leader and head of Harbor Branch's Visual Ecology Department, will use the submersible to deploy light-tight traps of her own design in hopes of bringing animals to the surface without damaging their eyes, as has typically been the case with past research. Eyes adapted to low light in the deep sea can be destroyed even by the relatively dim lights of a ship at night.

The traps are baited then left open on the seafloor. After a period of time, the doors close automatically capturing inside the animals that have come to feed. Traps are then retrieved and unloaded in a darkroom where Dr. Frank and colleagues can study how their visual systems respond to light. The overall goal will be to learn what these animals are able to see under conditions where humans can see absolutely nothing. Answering such questions will not only help the team better understand the importance and functions of the small amounts of light found in the dark world of the deep sea, but may also lead to the discovery of new ways to increase the sensitivity of various man-made detectors.





This Mastigoteuthis squid is one of many animal species the team hopes to observe during the expedition
Credit: HARBOR BRANCH/E. Widder




Dr. Charles Mazel from Physical Sciences, Inc., will be exploring fluorescence given off by deep -sea animals. Fluorescence occurs when an animal or object absorbs light of one color and then reemits light of, or glows, another color. In the ocean, detecting fluorescence can allow scientists to spot animals that would otherwise be too effectively camouflaged to see. Fluorescence is also important because the proteins that allow animals to fluoresce are used in genetic research and new fluorescent animals may contain proteins that offer novel benefits in such work.

Dr. Mazel will use powerful lights mounted on the front of the submersible to illuminate animals whose fluorescence will then be captured on the sub's video camera using a filter that blocks non-fluorescent light reflected back. The filter can also be removed using the sub's robotic arm to allow filming of non-fluorescent views for comparison.

To gain yet another new view of the deep, Dr. Justin Marshall from the University of Queensland, and colleagues, will be using polarized filters on the submersible video camera. Just as polarized sunglasses offer boaters a clearer view into the water by blocking out glare, polarized filters in the deep will allow scientists to see animals that hide from their predators--and normal cameras--using camouflage that exploits the properties of light polarization.

"There's just no telling what we'll be able to find using these new techniques," says Dr. Widder, "and that's the best part of exploration - discovering something totally new and unexpected. It just doesn't get any better than that."

Regular dispatches from the ship about each day's discoveries will be posted at Harbor Branch's expedition web site, www.at-sea.org, and articles written by the scientists about their research and the tools they will be using, as well as lesson plans for students for grades 5-12, can be found at oceanexplorer.noaa.gov.
-end-


Harbor Branch Oceanographic Institution

Related Fluorescence Articles from Brightsurf:

Researchers combine photoacoustic and fluorescence imaging in tiny package
Researchers have demonstrated a new endoscope that uniquely combines photoacoustic and fluorescent imaging in a device about the thickness of a human hair.

Researchers propose strategy to evaluate tumor photothermal therapy in real-time
Researchers from USTC reported an ''intelligent'' strategy of using organic nanoparticles to evaluate photothermal therapy efficiency on tumor in real time.

Instantaneous color holography system for sensing fluorescence and white light
The National Institute of Information and Communications Technology (NICT), the Japan Science and Technology Agency (JST), Toin University of Yokohama, and Chiba University have succeeded in developing a color-multiplexed holography system by which 3D information of objects illuminated by a white-light lamp and self-luminous specimens are recorded as a single multicolor hologram by a specially designed and developed monochrome image sensor.

Faster processing makes cutting-edge fluorescence microscopy more accessible
Scientists at NIBIB have developed new image processing techniques for microscopes that can reduce post-processing time up to several thousand-fold.

Fluorescence bioimaging
Scientists can monitor biomolecular processes in live tissue by noninvasive optical methods, such as fluorescence imaging.

High-security identification that cannot be counterfeited
Researchers from University of Tsukuba have used the principles that underpin the whispering-gallery effect to create an unbeatable anti-counterfeiting system.

Cervical precancer identified by fluorescence, in a step toward bedside detection
Researchers developed a method using fluorescence to detect precancerous metabolic and physical changes in individual epithelial cells lining the cervix, and can visualize those changes at different depths of the epithelial tissue near the surface.

General descriptor sparks advancements in dye chemistry
SUTD collaborates with international researchers to move away from inefficient trial-and-error developments in dye chemistry and quantitatively design luminescent materials.

Novel 3D imaging technology makes fluorescence microscopy more efficient
A research team led by Dr Kevin Tsia from the University of Hong Kong (HKU), developed a new optical imaging technology -- Coded Light-sheet Array Microscopy (CLAM) -- which can perform 3D imaging at high speed, and is power efficient and gentle to preserve the living specimens during scanning at a level that is not achieved by existing technologies.

Light-sheet fluorescence imaging goes more parallelized
In pursuit of 3D visualization of cells and organisms with minimal invasiveness and high spatiotemporal resolution, researchers demonstrated a new form of light-sheet imaging, coined CLAM, which allows scan-free, parallelized 3D fluorescence imaging that results in an even slower rate of photobleaching than scanning light-sheet imaging, yet without sacrificing the image speed and resolution.

Read More: Fluorescence News and Fluorescence Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.