You are here: Home » Biogeography » Nancy Foster Mission
Seafloor Characterization of the U.S. Caribbean |
|||||
 |
« Cruise Intro
Day 10: 2.10.2005
Nancy Foster Mission Cruise Update #11
Figure 1 shows the completed acquisition of NPS Inshore survey area. All have been quite pleased with the result and efficiency of data collection. We hope that it will serve NOAA Office of Coastal Services purposes for charting as greatly as it will the National Park Service and NOS for fulfilling the objective of seafloor characterization. The area represents a full range of habitats- flat and monotonous depositional areas with scattered macroalgae, areas of relatively high relief patch reefs with a complement of diverse soft and hard corals, a plethora of rhodolith field, and exceptional spur and groove in inshore areas. Well ahead of expectations, the team moves on to areas to the west in hopes of creating continuous multibeam coverage along the South shore of St. John and St. Thomas.
South of St. Thomas - The day ended with the science crew covering over 6 kilometers of habitat with three transects. Two transects east of Frenchcap Cay and one transect east of Capella Island investigated elevated mid-shelf ridges.
As was the surprise yesterday, much of the video along the ridges revealed a moon-like flat seascape. Infrequently sponges and corals seemed to gasp for breath amid a sea of rhodoliths and macroalgae. In some spots, it appeared as though the rhodoliths were a foot deep. None of the scientists had ever seen so many.
We occasionally glimpsed islands of high diversity. In these exceptional locations encrusting sponges and coral were shaded by dense forests of lush gorgonians. Fish darted among the vertical corals and some stopped to timidly peer from semi-concealed positions at the curious ROV gliding above.
The science team is working like a tuned, well-oiled machine. The ROV now slides into and out of the water and glides along predetermined transects effortlessly. We have now completed 90% of this year's objectives. In the next few days we believe there will be time to collect additional data.
Figure 2 – Coral debris covers a sandy depression south of St John. The unseen elevated ridges surrounding this depression were once rich with coral life, but now are cluttered with macroalgae.
Figure 3 – A diverse assortment of corals and sponges covers a small patch reef. This slightly elevated site appeared as an oasis within a sea of rhodoliths, serving as an ephemeral respite from a flat unadorned monotony.