10/18/05
Dave, a teacher from Michigan, sent the following:
From your map it appears your sample sites are between
400 m and 800 m in depth. Does depth play a significant role in selecting your
sites and if so, why such a range of depths?
Depth does play a significant role in determining
our dive sites because the corals we are targeting (Lophelia) only occur in the
deeper depths (between 300–900 meters). Although we know the coral is out here,
there are not many maps identifying the location of these coral mounds. We use the
ship’s sonar to help select target submersible sites.
Where does the Gulf Stream generally travel relative to your
sampling sites?
Generally the Gulf Stream moves
from south to north over our sites. When we launch the sub we have to consider the force
of the Gulf Stream on the descent of the sub. It is a good geometry problem to determine
where to launch the sub so that its angle of descent will make it land at its target site.
Shay, a sixth grader from Alaska asks:
What is your boat like?
Our boat, the R/V Seward Johnson, is 210 feet long. It is a research vessel which means
most of its deck is used to hold science equipment. The four-person submersible (Johnson-Sea-Link)
sits on the deck and is our primary means of collecting specimens. We have both a dry lab (for the computers)
and a wet lab (for processing the specimens). There is an environmental room, which is kept
cold so that we can keep some specimens alive for observations. In addition to the submersible
we use otter trawls, Neuston nets, dip nets, and plankton nets to collect specimens.
Do you have any pictures of seagrapes?
Unfortunately we don’t have any pictures of seagrapes. They are found in shallow water and we are in deep water.
