Team ends 1st leg of ocean expedition
Second leg to probe hard, high ground of Continental Shelf
Tuesday, August 6, 2002
BY LYNNE LANGLEY
Of The Post and Courier
Staff
The first leg of a national ocean adventure ended Monday in Shem Creek
as a team of Charleston marine scientists came ashore after 10 days
of deep-sea dives.
The expedition represents a new era of ocean exploration, said Capt.
Craig McLean, director of the National Oceanic and Atmospheric Administration's
new Office of Ocean Exploration.
George Sedberry, principal investigator on the voyage, said the mission
is "particularly exciting because we started using new technology
to explore the oceans."
Sedberry, a senior marine scientist with the S.C. Department of Natural
Resources, deemed the mission an absolute success after he returned
to land Monday evening.
McLean added, "This is a new way of doing business." He said
an interdisciplinary group of experts is approaching ocean study from
many different angles to answer questions about the nature of our sea?
"We want to open new doors," McLean said.
This mission, called Islands in the Stream, is gathering information
that is more broad-based than studies in the past and will spur research
by other scientists, he said.
New technology such as a state-of-the-art, deep-sea submersible let
Sedberry explore and, for the first time, see ocean features that he
had crossed hundreds of times on the ocean surface, he said. A wealth
of navigation software will provide, store and assemble the newly discovered
information, he said.
People will be able to visit an Internet site to view the sea bottom
off Charleston, watch a video of the depths and read a list of fish
species found there last week, fish that spawn there, currents and temperatures,
Sedberry said.
The first leg of the mission, which Sedberry led, focused on searching
for spawning grounds of fish that are commercially and recreationally
valuable and whose numbers are declining. Scientists dove in the submersible
on reef sites from the St. Augustine (Fla.) Scarp to a feature closer
to Charleston known as the Georgetown Hole.
They saw signs of courtship among hog snapper, scamp grouper and an
aggregate of hundreds of red snapper, Sedberry said.
"There are many interesting scientific questions that still remain
and need to be answered about that part of the ocean," McLean said
of the South Atlantic Bight, the East Coast stretching from Florida
to North Carolina. "It is important to our national understanding
of the marine world, the marine environment and marine resources."
The mission this year focuses on the bight and continues what began
last summer with the first Islands in the Stream expeditions. They discovered
new species, found new ranges of known species and produced better maps,
he said. Last year's voyages mapped more than 3,200 square nautical
miles.
Last week, German Ojeda of Coastal Carolina University used side scan
sonar in the dark of night to see the sea floor, distinguish sand and
mud from rock. The scientists used this information to determine the
most important places to dive in the submersible the next day. Scientists
wanted to visit a hard sea floor with structure where fish and other
marine life gather.
Information on hard bottoms in this region is so limited that maps based
on the data collected during the 10-day mission will be extremely valuable,
Ojeda said.
Leg one of Islands in the Stream, Exploring Underwater Oases, ended
Monday when the Carolina Clipper, a charter boat from Shem Creek, took
17 scientists to the Seward Johnson to begin leg two and picked up 19
from greater Charleston.
Leg two will explore the high, hard ground of the outer Continental
Shelf and the vast reefs of deep-water corals thought to form the slope
off the Carolinas. Data is so scarce that scientists have little knowledge
of the habitats, how they function ecologically and what species live
there. They're thought to include a number of commercially important
and unique fish species.
The final leg, which ends Sept. 1, will search for new medicines. The
sea may contain 80 percent of the world's plant and animal species,
McLean's office estimates. So far, 12 natural marine products are in
advanced trials or are being tested on people.
Scientists hope to find new sources of future drugs that might be used
to study, diagnose or treat such ills as cancer and heart disease and
infectious diseases.
The last deep-sea dives will deploy a special low-light camera and light-tight
traps to catch big-eyed creatures that dwell on the ocean bottom, where
virtually no light penetrates. The animals are thought to see bioluminescence,
light produced by a chemical reaction within an organism.
"We really have a great group of scientists with diverse backgrounds,
and we are sharing a lot of knowledge and expertise among us,"
Sedberry said. "Those that don't know the fish are learning about
them from the fish people, and the fish people are learning about the
sponges and corals from the invertebrate people. The geologists are
teaching us all things. We are coming up with interesting ideas for
classroom students as well. It is a learning experience for all of us."
Inside the deep-sea submersible, scientists filmed images of places
that people had never seen and took samples of sediment, rock and marine
life expected to include species previously unknown to science. From
the deck of the Seward Johnson, scientists collected a variety of samples
and will study fish to learn whether they were spawning.
Among other things, scientists found six venomous lionfish, natives
of the Indo-pacific, in three places at the edge of the Continental
Shelf off South Carolina.
"It's a really important discovery. Every time you go to the bottom,
you see one," Sedberry said. Lionfish are predators and may pose
a problem to native species, he said.
|