Dr. Edward Trippel, a research
scientist at the St. Andrews Biological Statlon, works with a gill net that
glows beneath the sea's surface, warning whales of Its presence.
Researcher modest about contribution
to new fishing net
A St. Andrews
scientist who was involved with a team that invented a fishing net that can
reduce the accidental death of whales and other sea creatures doesn't want to
take any credit for the invention.
On Wednesday, Dr.
Edward Trippel, a marine biologist at the St. Andrews Biological Station, first
estimated his role in the invention at 10 per cent and then called back later
to say that it should be only "zero. I am just a research scientist who was
involved in the field testing. The product was a done deal by that time."
This in spite of the fact that he quoted lead inventor
Norm Holy, a Pennsylvania chemist, as saying that if it weren't for Mr.
Trippel's persistence the net would probably have never gotten off the drawing
The team, which included a Massachusetts
commercial fisherman Don King, started testing the net in 1998. The team was
named as one of three winning entries in the International Smart Fishing
Competition sponsored by the Washington-based World Wildlife Fund, and received
$5,000 US. Fifty-three teams from 16 countries took part in the competition.
The contest seeks innovative fishing gear or methods that
reduce by-catch or accidental catch of non-target species in ways that still
allow fishermen to fish profitably.
separate the team's gill net from conventional fishing nets.
It glows in the dark. Its composition includes barium
sulphate, which he describes as a white chalky substance. The sun's UV rays
charge up the net in a few minutes and then it can glow for 48 hours.
Dr, Trippel, however, said the net's glow can be detected
ay depths of up to 30 metres. Beyond that it is too dark for the little light
it has to have any effect. Scientists, however, believe that it has enough
reflective properties to warn whales, dolphins and harbour porpoises. The net
emits yellowish-green light which whales are able to see.
The net is also stiffer than conventional nets, so sea
creatures can bounce off it and avoid getting entangled.
The net is made up of "weak" ropes - about half as strong
as those in conventional net - so stronger animals can break free. The floating
line of the net called the breakaway rope or "continuous weak rope" is weak and
once this breaks the net falls.
Dr. Trippel said that in
conventional nets guts of the birds that get entangled in them get stuck to the
mesh and this attracts other sea animals to the food. But because of the colour
and light they can see the net and don't go near it.
nets were tested with the aid , of the Grand Manan Fishermen's Association. The
research findings were extremely promising, significantly reducing the by-catch
of harbour porpoise and seabirds in gill nets in the area.
"We wanted to have something that was easy for the
fishermen to use that would be cost-effective," he said. "Prior to the nets, we
tried using acoustic alarms, but, while they were somewhat effective, they were
expensive, had to be maintained and we were a bit worried the harbour porpoise
would either get used to their noise or would be displaced because of their
Harbour porpoise use echolocation, the
identification of objects by reflected sound, to identify barriers. The use of
barium sulphate increases the reflectivity and stiffness of the net, which
appears to better alert the porpoises of a barrier.
research led to the development of "continuous weak rope" which also contains
barium sulphate and is dyed purple. The weak rope is being investigated in both
the gill net and lobster fisheries.
continue on the -reflective nets and weak rope in the Bay of Fundy this fishing