Ecological decline

The Australian Terrestrial Biodiversity Assessment found that riparian zones are declining over 73 per cent of Australia.

There has been a massive decline in the ranges of indigenous mammals over more than 100 years; in the past 200 years, 22 Australian mammals have become extinct - a third of the world’s recent extinctions. Further decline in ranges is still occurring and is likely to result in more extinctions.

Mammals are declining in 174 of 384 subregions in Australia and rapidly declining in 20. The threats to vascular plants are increasing over much of Australia; threatened birds are declining across 45 per cent of the country with extinctions in arid parts of Western Australia; reptiles are declining across 30 per cent of the country; threatened amphibians are in decline in southeastern Australia and are rapidly declining in the South East Queensland, Brigalow Belt South and Wet Tropics bioregions.

Our rivers are still carrying huge excesses of sand, mud and silt. Mud and silt washes out onto coastlines destroying seagrass and corals. The sand chokes up pools and riffles and fills billabongs putting intense pressure on inland, aquatic ecologies.

In 1992, the Mary River in southeast Queensland flooded carrying millions of tonnes of mud into Hervey Bay. A thousand square kilometres of seagrass died off decimating dugongs, turtles and fisheries. The seagrass has grown back but the problems of the Mary River have not been fixed. The banks have not been stabilised and the seagrass could be lost again at any time. A huge excess of sand working its way down the river is driving to extinction the Mary River cod and the Mary River turtle.

The situation in the Mary River is mirrored in catchments right across the country. Nationally, 50 per cent of our seagrasses have been lost and it has been this way for at least 20 years.

It is well known what the problems are. The causes of the declines in biodiversity are land clearing, land salinisation, land degradation, habitat fragmentation, overgrazing, exotic weeds, feral animals, rivers that have been pushed past their points of equilibrium and changed fire regimes. The individual solutions are often fairly simple: only when combined do they become daunting.

One of the problems is that the issues are reviewed at a distance. Looking at issues from a national or state perspective is just too complex: even if problems are identified broadly, it is difficult to establish local priorities. Looking at issues from a distance means that a focus on the immediate and fundamental causes of problems is lost.

There are rafts of administration, reports, computer models, guidelines and plans but the only on ground restoration and conservation is done by volunteers and farmers. Volunteers are valiantly struggling but it is too little too late. Farmers tend to look at their own properties, understandably, and not at the whole landscape.

Our existing environmental legislation deals exclusively with development and farming. In Australia, the entire urban footprint is 0.3 per cent of the continent. Land clearing in Queensland was 0.15 per cent of the state a year. With the relatively small areas involved, urban development and land clearing cannot be the main cause of continuing ecological decline in Australia.

Billions of dollars are expended by governments regulating farming and development. Billions more are spent by councils and the private sector. The ecological decline continues because we are focused on development and farming and substantially neglect restoration of landscapes. It would be preferable if business and farmers, with the support of countless consultants and modern environmental management methods, were left to their own devices to a large extent and public resources focused on the bigger picture.

There are solutions to some or all of our environmental problems: scientifically based sustainable grazing and agriculture; replanting and stabilising riparian zones; restoring fragmented habitat; applying appropriate fire regimes; and controlling feral species. But first of all it needs political will and a financial commitment.