(La dégradation environnementale affecte les pêches en Australie)
12 / 1997
A sustainable fishing industry depends as much, if not more, on a clean and healthy environment as it does on controls on harvesting pressure. In New South Wales (NSW), nearly two-thirds of the fish and shellfish spend some part of their life cycle in estuaries and the bulk of fishing effort is concentrated in the nearshore zone-areas most susceptible to environmental degradation.
Fishermen are affected by environmental damage and modification to the local ecology in a number of ways. For one, the loss and degradation of vital fish habitats reduce the numbers of fish being recruited into the fishery. There are well-documented cases of reductions in both the number of species and individual animals caused by industrial pollution and urban/agricultural run-off.
In terms of fish habitats, there is little doubt in the minds of fishermen that these have been heavily affected over the past 100 years. For instance, sea grass loss in NSW is phenomenal (a 50 per cent loss in the past 40 years) and this has reduced the nursery area available for juvenile fish and prawns. The loss of fish habitats has been attributed to many things, such as, too much water being removed from the rivers; obstacles to fish passage created by dams, weirs and river regulators (preventing fish access to spawning grounds and reducing stock availability); disruption due to introduced species like carp, trout and redfin; wetland drainage; pollution by nutrients and pesticides; and prevention of water from floods and small rises in the river from reaching spawning areas.
Some types of habitat losses are common in all areas of NSW. These include those arising from the impact of urban development and the construction of roads and railways. The latter facilities often have culverts, which block fish passage. Apart from this, with increase in pollution loads there is greater incidence of fish contamination and disease. Fish, which are contaminated or diseased, are unmarketable and the industry, at times, loses thousands of dollars due to disease.
The most common disease is the fungal infection called red spot, which is related to the input of acid water from overdrained wetlands. Public concern about contamination (even though this is relatively uncommon) has cost the industry millions of dollars in lost sales. The costs resulting from these problems are difficult to ascertain but it is not unreasonable to estimate them in the order of millions of dollars. The trickle-down effects into the community of the loss of commercial fishing activity are also difficult to quantify, but we do know that each dollar earned by a fisherman generates at least another dollar in the community. What is being experienced in NSW is unique to neither Australia nor many other countries of the world. From experiences elsewhere it is clear that the costs of repairing the damage are phenomenal, and that a case for preventing further damage by protecting fish habitats and managing them with a long-term view in mind is easier and cheaper to implement. It also makes common sense.
The NSW commercial fishing industry has made a major commitment to protect fish habitats and the broader aquatic environment throughout the state. Fishermen have done this principally through the Commercial Fishing Advisory Council and Ocean Watch, but many have become greatly involved in environmental issues personally at a local level. The common goal is to protect and enhance the natural environment and ensure that healthy fish stocks are available for future generations of fishermen (commercial and recreational) as well as seafood consumers. Unfortunately, their efforts have not received adequate support from the government. It appears that the commercial fishery is to be treated as the sacrificial lamb due to the incapacity of the government to tackle big problems: better to shoot the messenger than make the hard decisions.
It is evident that it is not enough merely to control fishing activity to support a sustainable fishery. As understanding about human-nature interactions increase, the need to be sensitive to the local ecology and to minimise interference in natural processes, becomes clear. Environmental degradation, depletion of vital natural habitats and interference with natural processes affect the viability of the fishery sector. As is happening in NSW, the fishery sector must organise to protect its interests and to lobby for a healthy environment. They must ensure that `developmental activities’, such as the construction of dams, roads and industries, interfere minimally with natural processes and with the ecology.
Articles et dossiers
LEADBITTER, Duncan, Don’t shoot the messenger in. Samudra Report, 1996/07, 15