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Efficacy Tests of the Whale-Free Buoy. Clifford A. Goudey Center for Fisheries Engineering Research MIT Sea Grant College Program, Cambridge, MA. Results from a project funded by the Northeast Consortium. Conventional Buoy and Stick. Buoyant force. Drag force. Whale’s motion.
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Efficacy Tests of the Whale-Free Buoy Clifford A. Goudey Center for Fisheries Engineering Research MIT Sea Grant College Program, Cambridge, MA Results from a project funded by the Northeast Consortium
Conventional Buoy and Stick Buoyant force Drag force Whale’s motion to Lobster traps Whale’s fin
Whale-free Buoy Buoyant force Drag force Whale’s motion Whale’s fin to Lobster traps
Prototype Production The need for a gradual reduction in stem stiffness vs. length that was met with 80 durometer urethane cast in a trombone bell.
Operational Tests Initial prototype tests were done by Capt. Mathew Thomson of Monhegan Island
Tests aboard the F/V Striker, December 2002 “The buoy stays upright in the water column. Paint stays on despite the cold. This picture was taken with a fair amount of tide running.”
“You have to use a dull gaff with the whale-free buoys so you don’t tear them up, but they hold in the gaff well.”
“The suppleness of the whale-free buoy stem is important. It doesn’t get stiff in the cold. The bonding between the buoy and the stem has stayed very secure, much to my amazement.”
“The rubberized end of the whale-free buoy goes around the hauler well and stays supple even though it is frigid cold.”
Efficacy Tests Pivot plate Submerged hook
Typical encounters with conventional buoys 5” x 11” with Plant stick 7” x 14” with Plant stick 5” x 11” with wooden stick 8” x 15” with Neptune stick 5” x 11” with 30” PVC stick 5” x 11” with 48” PVC stick
Typical encounters with Whale-free buoys 5” x 11” 7” x 14” 8” x 15” 8” x 15” with 18” stick 8” x 15” with 48” stick 7” x 14” short stem
Summary Findings Factors increasing entanglement risk: foul tide encounter larger buoy abrupt line/stick connection long upper stick blunt buoy shape Factors decreasing entanglement risk: fair tide encounter smaller buoy smooth line/stick transition short or no upper stick tapered buoy shape
Conclusions 1) The Whale-Free buoy is compatible with a significant sector of the fixed gear fishing industry. 2) The Whale-Free buoy significantly decreases the frequency of experimental snagging. 3) The adoption of the Whale-Free buoy by those sectors could reduce the risks of marine mammal entanglements. 4) The CFER buoy testing apparatus is effective in discerning the snagging potential of buoys.
Plans/Recommendations 1) The Whale-Free buoy U.S. patent application has been approved. 2) The Whale-Free buoy should be an alternative whale friendly gear modification in the TRT Plan. 3) MIT is seeking a manufacturer to produce the Whale-Free Buoy.
Acknowledgments Northeast Consortium Capt. Matthew Thomson, Monhegan Is., Maine Capt. Dave Marciano, Gloucester Matt Cadwallader, Seahorse Cinema, Boothbay Hbr. Andy Gallant, MIT Central Machining, Cambridge Gregory Rupert, Woods Hole, MA Rudy Pizzoferatto, Spongex, Inc., Shelton, CT