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MISSION BACKGROUND
Several spectacular deep-water reefs have been discovered off Florida in recent years, and all indicators suggest
these submerged wonderlands are nurseries for commercially important fish and vital habitat for numerous other
animals, including some that may produce chemicals capable of curing human diseases. Nonetheless, very little
is known about these reefs because exploration has been extremely limited, and long-term studies have been all
but non-existent. Harbor Branch Oceanographic Institution scientists are hoping to change that.
From May 31 to June 9, a Harbor Branch team will use the institution's
Johnson-Sea-Link II (JSLII) submersible,
sub-deployed time-lapse video and listening devices, and towed nets to perform the first comprehensive survey
of a Florida deep-water reef. In addition to Harbor Branch scientists, there will also be participants on the
expedition from the Ocean Research and Conservation Association; the University of Florida; the University of
Miami; the Florida Fish and Wildlife Conservation Commission;
Estuarine, Coastal, and Ocean Sciences, Inc.;
NOVA Southeastern University; and the
Florida Fish and Wildlife Research Institute. Goals for the project
will include a preliminary assessment of the diversity of fish, coral and other species; assessment of
factors responsible for surprising fluctuations seen during past expeditions in animal diversity and abundance
between seemingly similar locations; and identification of factors such as food type that are responsible for
the reefs' remarkable diversity.
Results of the research will be submitted to the Florida Oceans and Coastal Resources Council to aid in the
development of research goals and priorities for Florida deepwater reef studies. The information will also
help the South Atlantic Fishery Management Council and the National Oceanic and Atmospheric Administration
with ongoing efforts to formulate a management plan for these resources. The long-term goal will be to work
with state and federal agencies to secure funding for regular deep-reef surveys that will use results from
the upcoming expedition as a baseline to identify threats to the reefs and to contribute to the formulation
of the best management plans for their protection.
Deep reefs are common off the southeastern U.S., though most remain unseen because of a lack of exploration.
These reefs are characterized by mounds, slopes, and rock ridges, all of which can support a diversity of
life that rivals and at times surpasses shallow coral reefs. Deep-water reefs are found below the depth
that sunlight can penetrate, so corals there lack the algae that provide much of their shallow cousins'
food and have to rely instead on food carried to them by currents or sinking down from above. Harbor Branch
has discovered six new reefs since 2003 that are now under consideration for classification as marine
protected areas.
The survey expedition will focus on the Miami Terrace, a 65-km long platform that runs from South Miami
to Boca Raton about 15 miles offshore in depths from 650 to 2,000 feet (200 to 600 meters). Rock ridges
along the Miami Terrace provide habitat for a rich, deepwater reef ecosystem of corals, sea fans, sponges,
and fishes.
During the expedition, the team will locate and survey highly diverse areas and adjacent areas with lower
diversity in order to make comparisons. By analyzing video, photos, and collected samples, researchers will
assess and compare the abundance and distribution of fishes, sponges, and other animals found between sites
on the reefs.
Using information gathered with the submersible as well as a specialized trawl net that can be triggered to
open and close at certain depths, the group will also analyze the abundance and distribution of the small
animals and larvae known collectively as zooplankton at and above the sites. The zooplankton are of particular
interest as they are likely to be one of the key food sources that sustains the reefs. Organisms will also
be collected for tests to identify those that might produce chemicals with the potential to treat human
diseases, an ongoing area of research at Harbor Branch.
In addition to using the submersible to collect information about the reefs, the team will also be placing
video and acoustic monitoring equipment at study sites for longer-term monitoring. Time-lapse video
recordings will allow them to assess differences in the abundance and behavior of animals during the day
and at night.
Throughout the expedition, the scientists will work to carefully document signs of human activities related
to the reefs, such as the presence of lost fishing gear and trash.
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