prevention of cetacean bycatch wwf runner up award nholy et al

Prevention of Cetacean whales, dolphins, and porpoises Bycatch

© World Wildlife Fund
21st April 2005

Runner Up and $5,000 Award:
Prevention of Cetacean (whales, dolphins, and porpoises) Bycatch
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

Brief Biography

Norm Holy, a chemist, and inventor and fisherman
Don King got together 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 harbour 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.

Dr. Norm Holy

Invention

Their entry is a clever 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 consist of 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.

Don King

Holy, Trippel and King's gillnets consist of a single wall of netting that is injected with barium sulphate, which makes the netting stiffer less likely to tightly tangle around a fin, flipper or tail. Barium sulphate 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.

With more testing and implementation the unusual ideas put forth by this team could help reduce whale, dolphin, and porpoise bycatch in gillnets, and inspire other inventive approaches.

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