Wednesday, Sept. 5 - 2300 hrs
It's great to be back at sea. This is a beautiful and comfortable
vessel with about 40 people on board, half of whom are scientists.
We boarded the R/V Seward Johnson II (Fig. 1) at 2000 hrs in Ft.
Pierce, FL after a long and tiring van ride from Charleston. Drs.
George Sedberry and Jack McGovern of the SC DNR, Josh Loefer (DNR
research assistant) and Jill Jennings (grad student) accompany me.
We are taking part in a leg of the NOAA Islands in the Stream Expedition
(Fig. 2) which began in Belize this past summer and has made a circuitous
journey along the path of the surface currents that eventually lead
to and become the Gulf Stream. The last several legs of the expedition
focus on areas within the South Atlantic Bight (Fig. 3) - a coastal
margin region that stretches from Cape Hatteras, North Carolina
to Cape Canaveral, Florida. Here, the Gulf Stream transports its
warm, tropical waters northward, hugging the edge of the southeastern
U.S. continental shelf (Fig. 4).
On our mission we will explore the undersea "island" of
life that occurs along the edge of the continental shelf, 70 miles
east southeast of Savannah, Georgia. This location, known as the
Savannah Scarp (Fig. 5), is about 200 feet deep and is known by
fishermen as a location providing habitat to many commercially important
species of demersal (or, bottom-dwelling) fish, such as gag grouper
and scamp. These and other fish are found to inhabit areas often
referred to as either "hardground" or "live-bottom."
Hardground indicates that the seafloor is exposed, solid, rock instead
of being covered with loose sediment, or grains of sand and silt.
They are "live-bottom" because many invertebrate organisms
such as sponges, bryozoa and coral require a hard, immobile surface
on which to attach and grow. The result is that a small reef community
of sessile organisms can inhabit hardgrounds, attracting fish and
other mobile organisms. The purpose of our cruise is to see first-hand
these live-bottom communities and to compare and contrast them with
other hardground/live-bottom reefs along the South Atlantic Bight
coastal margin.
After stowing gear, and receiving a brief introduction to the science
party and overview of the mission, we settled into our berths. Thunder
shook the ship and the lightning flashed through our porthole, making
my new, temporary home somewhat surreal.
on to Thursday
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