NOAA Ship Ron Brown-Teacher Logbook July 20, 2001

Teacher Logbook - NOAA Ship Ron Brown

image of bacterial traps, click for full size

Bacterial traps are pictured here at Marker-33, amidst several experiments. There are 2 bacterial trap packages in this image (3 round cylinders/package - front center). Other experiments shown are an iron-osmoanalyzer (large white-yellow object to the left of the traps) and a moored temperature recorder (lower right).

image of limpets collected by suction sampler click for full size

The suction sampler is used to collect macro and micro biological samples, as well as sediment and small rock chips. Limpets from the area of the '98 lava flow are being sucked up through the hose and deposited in bottles on the ROV.

Jeff Goodrich's Sealog:
Axial Volcano: 1998 lava flow
July 20, 2001

Plop. Another bac-trap in the bio-box. Nice shot Big Keith! (photo right) Microbial communities abound and form the base of the food chain at hydrothermal vents. Microbiologists Craig Moyer and Jeff Engebretson capture these critters in special plexi-glass containers with 200-micron nitex screens. They are designed to be placed over relatively cool diffuse vents and transmit hydrothermal fluid through them. Inside the traps are fiberglass strings to provide substrate for optimal bacterial growth. There is no grazing pressure from the various types of worms that inhabit these areas. The traps pick up very different microbial communities than the ROPOS's slurp sampler, a vacuum system that sucks up bottom substrate and deposits it in bottles. According to Jeff the bac-traps are a "bacterial utopia."

Once the slimy traps are brought up to the ship they are immediately frozen in dry ice. Back at their Western Washington University lab they will extract, then identify DNA patterns at different vent sites to compile community fingerprints. Very little is understood about how these organisms exist as a community. Ultimately they will cluster each venting area based on its bacterial community.
Craig and Jeff are attempting to determine the influence of macrofauna (larger animals) and vent chemistry on supporting a particular microbial community. Also, they are trying to figure out how much bacterial communities alter the chemistry of the vent fluids and how they aid in the weathering of ocean floor rocks. Since microbial communities are extremely old they may provide some insight into the field of astro-biology.