The
Tasmanian recreational gill net fishery is the most destructive and unsustainable
fishery in our State Waters.
Tasmania
probably has the most permissive recreational net fishing regulations of any state
in the developed world. In Australia, recreational net fishing is not permitted
in any other State waters on the eastern seaboard.
Using
Government figures, approximately 80% of Tasmanian recreational net fishers target
the east coast (Lyle & Smith, 1998) and 6685 graball net licences were issued
during the 1997/98 season, and 2683 of these licence holders were licensed to
hold a second net (Lyle & Jordan, 1999).
Simple
arithmetic [(6685 + 2683) X 0.80 X 50m / 1000m] indicates that more than 370 kilometres
of graball net were being used on Tasmania's East Coast when the data was collected.
This is approximately the same as the straight line distance from Banks Strait
in the north east to South East Cape. It is hard to see how this level of fishing
pressure can be sustainable.
It
should also be remembered that there is currently no absolute limit on the numbers
of nets used by recreational fishers. It would be possible for thousands of new
fishers to take up net fishing next year. The potential latent fishing effort
in the recreational fishery very large.
Fishing
is almost certainly having major impacts on Tasmania’s coastal ecology. The best
evidence for this has come from research that has been carried out to assess the
effectiveness of the marine reserve at Maria Island. After just a few years of
protection, numbers of fish longer than 33 centimetres have increased markedly
(a rise of over 240% in six years ). In addition, bastard trumpet, a species which
is particularly vulnerable to net fishing, are relatively common inside the reserve
but practically absent outside (Edgar & Barrett, 1999).
In
my experience, recreational gill nets are the most commonly seen form of fishing
used to target reef fish on Tasmania's east coast and are therefore likely to
be a major cause of this impact.
There
do not appear to be any practical mechanisms to manage this fishery on a ecologically
sustainable basis. Collecting adequate information from the fishery is a major
practical problem, given the number of fishers and the likely accuracy of reporting.
Lack of basic scientific knowledge about target species simply adds to the difficulty
of ensuring that ecological impacts of this fishery are sustainable.
As
a diver, I have actually seen the larger fish disappear from a small reef, presumably
due to recreational nets, as it was intensively fished by recreational net fishers
during one Easter holiday.
Smaller
fish also suffered, and many of these died in the net and were simply wasted and
discarded as being too small to eat or not being worth the trouble of cleaning.
And
of course fish are not the only victims. Dolphins, penguins and other animals
can easily become entangled and killed in nets. A ranger at Rocky Cape told me
of one instance where more than 20 fairy penguins were killed by one gill net
in just one night of fishing.
Bycatch
of undersized fish, and protected species such as marine mammals and sea birds,
will always be a major problem for this fishery, whatever management regime is
adopted. Concerns about bycatch alone are enough for the Tasmanian Conservation
Trust position that recreational graball nets should be phased out as soon as
possible. Tasmania should follow the lead of the other eastern States and ban
recreational graball nets from State waters.
Most
of the recreational nets I have come across while diving over the last 25 years
have contained fish that were undersized or dead and inedible. I find this waste
of animal life very disturbing.
Less
than 7% of the 100 000 or so sea fishers in Tasmania use gill nets. It would appear
that as well as the environment, the majority of other sea fishers are also losing
out, as most reef-dwelling scalefish caught by recreational fishers seem to be
caught by nets and this is clearly having an impact on the numbers of fish available
to other recreational fishers.
The
State Government's changes to soak times and the associated buoy marker system
will do little prevent the major environmental impacts of recreational graball
nets. There are simply too many nets in the water, and both the environment and
line fishers are paying the price.
The
TCT believes that the use of recreational gill nets under the current management
system is inappropriate. Perhaps attended nets and two hour soak times will make
this form of fishing more sustainable. It is certainly a major issue that requires
basic fisheries research, public education, and consideration of new management
strategies. It is one of the most important issues relating to natural resource
management in Tasmania's coastal marine environment.
Jon
Bryan
jonbryan@southcom.com.au
References
Edgar,
G. J. & N. S. Barrett. 1999. Effects of the declaration of marine reserves
on Tasmanian reef fishes, invertebrates and plants. Journal of Experimental Marine
Biology and Ecology 242: 107-144.
Lyle
J.M. & Jordan A.R. 1999 Tasmanian Scalefish Fishery Assessment - 1998. Tasmanian
Aquaculture & Fisheries Institute, University of Tasmania, Hobart.
Lyle
J.M. & Smith J.T. 1998 Pilot survey of licensed recreational sea fishing in
Tasmania. Marine Resources Division, Marine Research Laboratories - Taroona, Department
of Primary Industry and Fisheries, Hobart.