There are many social, economic, and political challenges to addressing alluvial gully erosion in the Normanby catchment on Cape York Peninsula. Motivational aspirations of graziers can range from strong ‘economic & financial’ to ‘stewardship & lifestyle’ motivations, which can influence conservation ethics and willingness to participate in and successfully complete government programs (e.g., Reef Rescue). Conservation funding programs need to be tailored to match and utilise these intrinsic motivations.
The grazing industry of the Normanby catchment and Cape York Peninsula is struggling economically and is in transition due to the long distance to markets, the extreme wet-dry climate, low soil productivity, land degradation from erosion and weed invasion, increased fixed and variable costs (e.g., rates, labour, fuel, material, feed), stagnant cattle prices, and increased debt levels associated with development and competition pressures. The result is little to no extra income or time to reinvest in long-term property management or soil conservation actions such as gully erosion control.
The total cost (commercial retail) of intensive gully treatments conducted in this study ranged from $3000 to $6000 for 0.2 ha, which included heavy equipment hire and labour, gypsum, hydromulch or compost, and fencing. Using local labour, machinery, and materials from individual properties might be able to reduce this to $2000 for 0.2 ha. This equates to $10,000 to $30,000 per hectare for intensive gully treatment, which is well above the average costs of grazing properties in the Normanby catchment (< $100 per ha). This direct intervention is most applicable where key infrastructure is threatened (e.g., roads, fences, yards, buildings, dams, key waterholes) or where young, incipient gullies can be stopped to prevent major future erosion and land loss. Direct intervention during this project was able to reduce gully erosion for $375 per tonne, which is less than the average sediment erosion abatement cost of $600/tonne paid by the Reef Rescue program. To reduce the estimated 736,400 tonnes per year eroded from alluvial gullies by 10%, it would cost $27,600,000 at $375 per tonne. Or alternatively, if 2000 ha of mapped gully in the catchment was treated with intensive intervention at $2000 per 0.2 ha, it would cost $20,000,000. Investing this level of government or market-based funding in the Normanby catchment might be better spent on purchasing large areas of degraded river frontage on specific cattle properties, and taking them out of cattle production as ‘soil conservation areas’ (Plate 5; Plate 17).
A fundamental paradigm shift in government policy and investment targets is needed to reduce gully erosion and sediment yields. Current cost-share programs are not achieving water quality improvements at the catchment scale in the Normanby catchment. Land management investments for erosion prevention and control should be driven by a holistic, long-term, process-based catchment-wide perspective, rather than relying on small, discrete, short-term projects with questionable benefits that treat symptoms rather than causes or only promote property development.
Targeted investment for gully erosion control at large mapped ‘hot spots’ (i.e., dispersible sodic soils on river terraces and adjacent floodplains) is needed using large-scale land management changes and localised intensive rehabilitation actions. Several priority river frontage areas for large-scale erosion management actions – such as cattle destocking to create soil conservation areas – have been identified in the Normanby catchment (e.g., the Granite Normanby River, Plate 5; Plate 17). Funding for large-scale actions could come from government investment for public benefit, market-based solutions (payment for ecosystem services of carbon, biodiversity, soil retention), and/or land utilization/tenure trading to destock cattle from highly erodible soils and develop more productive, less erosion prone soils for agricultural and economic benefit. However, government or market-based investments for combined carbon sequestration, biodiversity improvement, and soil conservation must pass the ‘integrity’ test by going beyond normal practice, be measurable and rigorously monitored, and be subject to peer review.
In addition to large targeted investments and incentives, a renewed emphasis should be placed on extension of knowledge, training, and certification programs that are founded within locally-based and long-term government funded programs [e.g., a re-instated Soil Conservation Service (SCS), Primary Industries, Landcare, Natural Resource Management (NRM) agencies]. These programs should focus on integrated property planning for erosion reduction and control and monitoring of results. Machine-operator certification programs (e.g., roads and fences) should be prerequisites for government funding for erosion control. The design, implementation, maintenance, and monitoring of more complicated gully erosion control projects might be best conducted by a team of qualified experts and practitioners (e.g., a re-instated Soil Conservation Service and geomorphologists).
For the Normanby catchment and Cape York Peninsula, a mixture of larger positive incentives and investments, extension and outreach, and long-term soil conservation programs will be needed to cumulatively reduce erosion at the catchment scale.