Australia State of the Environment Report 2001 (Theme Report)
Prepared by: Ann Hamblin, Bureau of Rural Sciences, Authors
Published by CSIRO on behalf of the Department of the Environment and Heritage, 2001
ISBN 0 643 06748 5
Accelerated erosion and loss of surface soil (continued)
'Stocking rate' and 'stocking density' are defined, calculated, and used in different ways. Stocking density is the number of animals held on a property divided by the area of grazing land. On properties, the critical production issue is the number of animals grazing each paddock over a particular duration. Hence, 'set stocking rate' (in which a certain number of animals per hectare are grazed all the time) is distinguished from 'rotational or cell grazing' (in which animals graze in one area for a period, and are then moved to a fresh area). Where plant growth has a marked seasonal growth flush, a high stocking rate with rotational grazing is more productive and less liable to cause erosion from over-grazing than set stocking (Wheeler et al. 1987).
The slow downward trend in sheep numbers and fluctuating or increasing cattle numbers during the 1990s has been described earlier in this section. Higher densities of animal production are associated in the main with the mixed farming zone, apart from the pastoral regions of central and southern Queensland.
Intensive animal units (feedlots) are predominantly located in southern Queensland and New South Wales, adjacent to areas where feed grain (e.g. sorghum, barley, chickpeas) is grown. They have increased in number and size in the 1990s. North-eastern Australia still dominates beef production. Although sheep predominate in southern Australia, with significant numbers in northern South Australia, they are also spread throughout the pastoral zone of central and south-western Queensland, and there is a scattering in the Carnarvon to Gascoyne regions of Western Australia.
Adjustments to climate variability and droughts differ, depending on opportunities for alternative income and diversification (off-farm earnings, tourism, mining and service industries). In very general terms, stocking rates across the continent have always varied with the overall productive capacity set by total rainfall. Figure 19, compiled using data from a recent study of 500 wool producers across all regions, shows this, but it also shows the big variation that exists within each region as well (Woolmark Company 1999).
Figure 19: Stocking rates of sheep in the three major zones, compared with the performance of growers (decile 10 = highest profitability).
Source: Woolmark Company (1999)
Figure 19 shows that higher stocking rates (based on grazing area, not total farm area) are associated with better overall farm financial performance. Within each region, lower stocking rates were associated with poor performance across all parameters.
The key factor explaining these variations was farmers' attitudes to farming (Woolmark Company 1999). Where farms were being run as a business, the range of operating and management practices were similar to those of any business, and farms were relatively profitable. Where farms were run more as a 'lifestyle' activity, performance tended to be poor. When the performance index included stocking rate, the correlation was very high between management practices and financial performance (70% of all variation explained). Without stocking rate, management still accounted for nearly half the variation.
Nevertheless, while very low stocking rates are associated with very poor and unprofitable farms, high profits were associated with a suite of practices, including good pasture grazing management, as well as animal health, marketing skills, and forward planning, not just a high stocking rate.
Figure 20: Relationship between return per animal and stocking density (all regions).
Source: Woolmark Company (1999)
In shires within the Intensive Land-use Zone (which includes the high rainfall zone, the sheep-cereal zone, and the fringes of the pastoral zone), variations in fodder demand over seasons have been compared with available feed supply over the period 1983-1997 for this report (Valentine and Unkovich 2000). An analysis of the ABS statistics over the period 1983-1997 for a range of shires in different climatic regions showed that between 10 and 50% of available feed was utilised. Clearly, stock numbers fluctuate quite widely from one season to another, but when up to 40-50% of the available feed is consumed in a season this is unsustainable. For example, Valentine and Unkovich (2000) noted that the Shire of Yass had a very dry season after several average or wet seasons. At such times farmers have difficulty in rapidly reducing their stock numbers. In 1994 Yass has a very dry year after a decade of good seasons in which stock numbers had built up from very low levels in 1983; the grazing pressure reached critically high levels and over 40% of feed was utilised across the entire Shire. This is when overgrazing is liable to produce erosion-wind erosion at the time of drought (as demonstrated in the Accelerated erosion and loss of surface soil section) and sheet erosion when eventually the first heavy rain falls to break the drought.
In the rangelands there are substantial differences in modes of operation between individual properties (stations). While these tend to be larger in the more arid western half of the continent and smaller in Queensland and New South Wales, the major differences in management practice relate to income (cash operating surplus) and skills base. Larger companies are more likely to have sufficient capital to be able to take advantage of better technologies. Of approximately 4200 stations in all, 7 major companies together own 110 stations, covering nearly 50 million hectares, spread across the most productive and reliable grass-dominated regions. Because they have a range of properties in different types of country, these companies are able to move animals from one area to another to maintain productive capacity. The use of information technology is also an essential part of management in most companies today:
'We can press a button in our office in East Perth and get a satellite photo of every hectare of a property thousands of kilometres away, We can view them and say 'That's a bit overgrazed' or 'That paddock is looking fantastic'. It is revolutionising the way we look after the land'.
- Janet Holmes Court, owner of Heytesbury Pastoral Company
(quoted in The Australian, 5 February 2001)
At the other end of the scale are the small individual family stations that have been struggling with inadequate capital assets and limited opportunity for expansion or diversification. The regions where this scenario is common include the Murchison-Gascoyne region of Western Australia, the mulga lands of south-western Queensland, and parts of the Western Division in New South Wales. In these areas most stations have operated at a loss for over a decade, and cannot take advantage of new management techniques, or use the big company option of moving stock from station to station as seasons vary. Recent studies, such as the one undertaken for the New South Wales government by Kerin and Hyder Consulting (2000), reiterate the need to restructure such regions, and revise the pastoral laws governing leasing arrangements, duration and property size.
In some regions there has been a significant degree of diversification away from reliance totally on pastoral activities. For example, a recent survey of the beef industry showed that more than 75% of beef farmers had some degree of off-farm income, and the proportion of specialist beef producers has fallen in recent years (ABARE 1999). Tourism, mining and services industries provide an increasing alternative to primary industries in many grazing areas. Service industries and government payments support the majority of household incomes in the rangelands . Between 1991 and 1996 most non-metropolitan areas showed an average increase in employment in servicing industries of 19.8%, slightly higher than that experienced in metropolitan areas (17.3%). The increase was over 20% in all rangeland regions except South Australia (Haberkorn et al. 2000). Mining employs more people than agriculture in the remote north-west while service industries employ more than agriculture does in inland Queensland and up the eastern coastal zone. Loss of the agricultural workforce has been most marked in the dryland cropping zone and inner pastoral regions, especially inland (south-western) Queensland and western NSW since the prolonged drought in the early 1990s.
Social, community services and tourism employment is particularly high in the Northern Territory, north-western Western Australia and the Cape York Peninsula, where Indigenous populations are high, or where there are tourist attractions such as the Kimberleys, Uluru and Kakadu (Haberkorn et al. 2000).
Average stocking rates have decreased in some regions during the 1990s, partly because of concerns graziers and resource managers have consistently expressed over problems of land degradation and grazing pressure. This has been more noticeable in the pastoral zone than elsewhere. In much of the sheep-cereal and high rainfall belts, financial response to low commodity prices, particularly to wool, has been a major influence in turning farmers to diversification or alternative enterprises. In some areas that are heavily reliant on grazing industries, and where properties are too small to be viable in today's trading terms, stocking densities are too high in drier seasons, and do not adjust rapidly to changing conditions. Occasionally (e.g. west of Charters Towers in central Queensland) a few graziers have managed to destock down to 25-30% of former numbers with increased productivity and profitability (Taylor pers comm.), but this is rare.
Nevertheless there is a high degree of conservatism in actual land use in grazing regions of the continent, as shown in the small change to the area of pastoral leases in Table 19, and described in the 'Physical changes to natural habitats' section relating to land use change. So long as the infrastructure of intact fencelines, watering points, yards and sheds are maintained, grazing will remain the predominant land use across much of Australia, while its intensity and impact on vegetation fluctuates rather rapidly in response to prices, and more slowly with some lag in response to seasons.