The "Bushmaster", a collecting net designed to recover an entire bush of tube worms including all the species that live in association with the worms. Click image for larger view.
The "Bushmaster" and the "Chimneymaster"
Charles Fisher
Pennsylvania State University
The "Bushmaster" and "Chimneymaster" are original instruments created by Charles Fisher's team at Penn State to collect communities on and around hydrothermal vents. The Bushmaster and Chimneymaster are large collection nets that can be closed by the submarine using a system of hydraulic cylinders and cables. They collect intact communities of tube worms and all associated fauna, either on the seafloor (using the Bushmaster) or on a sulfide chimney (using the Chimneymaster). On board the ship, and back in the laboratory, every single animal collected with these nets is identified and counted, and a variety of other measurements made on most of them. Because these collection devices are so efficient (catching almost everything larger than about 64 micrometers or 0.0026 inches) discoveries of new species in the collections are often made.
This is the ìBushmaster Juniorî collection device in its "holster" on the front of the sub prior to launch. Click image for larger view.
During a tubeworm bush collection, the net is lowered over the top of a tubeworm bush with the mechanical arm of the submersible. A metal cable on the bottom is then cinched closed, collecting the tubeworm bush and all of the animals inside. The fine-meshed net of the Bushmaster is placed into a small container that is also lined with a net so we don’t lose anything on the way to the surface.
Once it reaches the deck of the ship, we place the collection into a large tub and carefully remove all of the organisms captured along with the tubeworms. Once these other animals are removed, the bush is taken out of the tub and wrapped in plastic. We preserve the aggregation and bring it back to Penn State where we measure and weigh each of the individual tubeworms in the bush. By collecting bushes from different sites, we can see how the communities associated with sulfide chimneys are different throughout the region.
