2005 Runner-Up Prize Winners

Altering the Chemical Properties of Nets to Prevent Bycatch of Cetaceans (whales, dolphins, and porpoises)

Dr. Norm Holy (chemist), Better Gear, LLC, USA
Dr. Ed Trippel, research scientist, Fisheries and Oceans Canada, Canada
Don King (fisherman), Homeward Bound, Inc., USA

Norm Holy, a chemist and inventor met fisherman Don King in 1988 when Dr. Holy came up with a degradable nylon that could be used in the ocean on gillnets. He sought the expertise of Don King and together the two tested the ropes in Gloucester, Massachusetts.

They continued to collaborate on projects and their next effort produced a gillnet that reduces bycatch of harbor porpoises. Dr. Holy and Mr. King brought their idea to research scientist Ed Trippel, who has researched bycatch of harbour porpoise in Atlantic Canada for more than a decade and who was able to manage the testing of the ropes in the Bay of Fundy. This group proved to be a winning combination of chemistry, biology and fishing expertise.

Winning idea
The team's winning entry was a combination of different ideas that could help marine mammals detect and avoid gillnets before coming into contact with them as well as allow them to escape unharmed if they still end up tangled in the net. To create avoidable, detectable, safer gear, the team tinkered with the chemical properties of ropes.

Normal gillnets form a single wall of netting that is kept vertical by a line on top called a "floatline" and a weighted rope on the bottom called a "groundline." The net is designed in such a way that when a fish enters the net it gets caught by the gills. Gillnets allow smaller fish to swim through unharmed but they are a huge threat to whales and dolphins, causing hundreds of thousands to die each year. These marine mammals can get tangled in the net itself, the groundline at the bottom of the net or the floatline at the top of the net.

Holy, Trippel and King's gillnets consist of a single wall of netting that is injected with barium sulfate, which makes the netting stiffer less likely to tightly tangle around a fin, flipper or tail. Barium sulfate also makes the nets more acoustically detectable for whales, dolphins and porpoises that are using echolocation to find objects.

The ropes they use for float lines are specially designed to be easily broken (under a force of 1,100 lbs) so large cetaceans can wrestle their way free. In order to keep cetaceans away from the floatlines in the first place, the team designed a glowing rope that may visually deter the animals.

The Barium Sulfate Nets are currently being trialed as part of a 2 year experiment to find a solution to the bycatch of Franciscana dolphins off the coast of Argentina. WWF-US and FVS have provided funding for these trials and the first trials conducted in Jan 2008 proved very successful. The nets may also have potential to address the issue of vaquita bycatch in the Gulf of California.

Modifying Shrimp Trawls to Prevent Bycatch of Non-Target Species in the Indian Ocean

Dr. Boopendranath, principal scientist, Central Institute of Fisheries Technology, India
Dr. Pravin, scientist, Central Institute of Fisheries Technology, India
Mr. Gibin Kumar, senior research fellow, Central Institute of Fisheries Technology, India
Mr. Sabu, senior research fellow, Central Institute of Fisheries Technology, India

This device was recently featured in a demonstration and training workshop, cosponsored by industry and the Central Institute of Fisheries Technology . Regional optimization trials with fishermen are also being undertaken in a number of regions around India. An important issue retarding the uptake of this and other bycatch devices in this country is the loss of potential bycatch as a payment for the crew. A political or legislative solution is being investigated.

Winning idea
This team's entry specifically addresses the bycatch problems faced by shrimp trawlers in the Indian Ocean. They developed a system of angled metal grids and net meshes that work to reduce bycatch of undersized shrimp and fish in trawls.

Trawl fishermen in India and other tropical fisheries depend on both finfish catches and shrimp catches to keep the commercial operations economically viable. Christened the Juvenile Fish Excluder cum Shrimp Sorting Device (JFE-SSD) by its inventors, this solution traps mature shrimp in the bottom portion of the net while allowing juvenile shrimp to swim out of the mesh net unharmed. The device also retains mature finfish in the upper portion of the net while allowing small fish of low commercial value to safely exit the shrimp trawl.

The sorting of the shrimp and the finfish between the lower and upper parts of the net enhances profitability because it reduces sorting time on the deck which increases the useful fishing time of the trawler fishermen, and it prevents shrimp from becoming crushed under the weight of fish and bycatch hauled on deck which increases the shrimp's market value.

The Barium Sulfate Nets are currently being trialed as part of a 2 year experiment to find a solution to the bycatch of Franciscana dolphins off the coast of Argentina. WWF-US and FVS have provided funding for these trials and the first trials conducted in Jan 2008 proved very successful. The nets may also have potential to address the issue of vaquita bycatch in the Gulf of California.

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