Efficacy Tests of the Whale-Free Buoy

Clifford A. GoudeyCenter for Fisheries Engineering

ResearchMIT Sea Grant College Program,

Cambridge, MA

Results from a project funded by the Northeast Consortium

Buoyant force

Drag force

Whale’s motion

Whale’s finto Lobster traps

Conventional Buoy and Stick

Buoyant force

Drag force

Whale’s motion

Whale’s finto Lobster traps

Whale-free Buoy

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.

Initial prototype tests were done by Capt. Mathew Thomson of Monhegan Island

Operational Tests

“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.”

Tests aboard the F/V Striker, December 2002

“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.”

Detail of whale-free buoy in hauler

Efficacy Tests

Pivot plate

Submerged hook

Experimental Methods

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

5” x 11” Spongex with Plant stick

7” x 14” Spongex with Plant stick

5” x 11” Spongex with wooden stick

8” x 15” Spongex with Neptune stick

5” x 11” Spongex 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

Small Whale-Free Buoy (5” x 11” Spongex float)

Medium Whale-Free Buoy (7” x 14” Spongex float)

Large Whale-Free Buoy with 18” PVC stick)

Large Whale-Free Buoy with 48” PVC stick)

Medium Whale-Free Buoy with shortened stem

Summary Findings

Factors increasing entanglement risk:foul tide encounterlarger buoyabrupt line/stick connectionlong upper stickblunt buoy shape

Factors decreasing entanglement risk:fair tide encountersmaller buoysmooth line/stick transitionshort or no upper sticktapered 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