Recreational gill nets - an environmental disaster
Jon Bryan 21 July 2008
Tasmanian Conservation Trust
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 proposed 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 will continue to lobby the State Government to stop the destruction caused by recreational gill netting. You can help too, by writing to local papers and/or the Government to support our position.
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.
This dolphin drowned in a recreational gill net in the D'Entrecasteaux Channel. Photo ã Jon Bryan 2000.
Trumpeter are very susceptible to gill netting. Once very common along Tasmania’s east coast this species has almost disappeared. Almost all trumpeter that are caugt are immature and below the legal size limit. If undersized fish are released, many will die due to injuries from the net. Photo ã Jon Bryan 2000.
According to Government figures, approximately 370 kilometres of gill net is used by recreational fishers on Tasmania's East Coast. The black line on the map indicates how this length of net compares to the length of coastline being targeted.