Contemporary livestock carrying capacities for pastoral properties in Northern Australia: a methodology for integrating objective data on pasture growth and condition

Hamilton, Jane; Chilcott, Chris; Savage, Darryl

doi:10.1071/ea08035

Cited by 4 publications

(3 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A GRASP-based method for estimating paddock LTCC has consequently been developed using rainfall, land type, land condition and water point distribution in individual paddocks (Hamilton et al, 2008). Although relatively objective, such estimates of LTCC must nevertheless be used with caution.…”

Section: Strategic Management Of Stocking Ratesmentioning

confidence: 99%

Sustainable management for rangelands in a variable climate: evidence and insights from northern Australia

O’Reagain¹,

Scanlan²

2013

Animal

View full text Add to dashboard Cite

Inter-annual rainfall variability is a major challenge to sustainable and productive grazing management on rangelands. In Australia, rainfall variability is particularly pronounced and failure to manage appropriately leads to major economic loss and environmental degradation. Recommended strategies to manage sustainably include stocking at long-term carrying capacity (LTCC) or varying stock numbers with forage availability. These strategies are conceptually simple but difficult to implement, given the scale and spatial heterogeneity of grazing properties and the uncertainty of the climate. This paper presents learnings and insights from northern Australia gained from research and modelling on managing for rainfall variability. A method to objectively estimate LTCC in large, heterogeneous paddocks is discussed, and guidelines and tools to tactically adjust stocking rates are presented. The possible use of seasonal climate forecasts (SCF) in management is also considered. Results from a 13-year grazing trial in Queensland show that constant stocking at LTCC was far more profitable and largely maintained land condition compared with heavy stocking (HSR). Variable stocking (VAR) with or without the use of SCF was marginally more profitable, but income variability was greater and land condition poorer than constant stocking at LTCC. Two commercial scale trials in the Northern Territory with breeder cows highlighted the practical difficulties of variable stocking and provided evidence that heavier pasture utilisation rates depress reproductive performance. Simulation modelling across a range of regions in northern Australia also showed a decline in resource condition and profitability under heavy stocking rates. Modelling further suggested that the relative value of variable v. constant stocking depends on stocking rate and land condition. Importantly, variable stocking may possibly allow slightly higher stocking rates without pasture degradation. Enterprise-level simulations run for breeder herds nevertheless show that poor economic performance can occur under constant stocking and even under variable stocking in some circumstances. Modelling and research results both suggest that a form of constrained flexible stocking should be applied to manage for climate variability. Active adaptive management and research will be required as future climate changes make managing for rainfall variability increasingly challenging.Keywords: grazing strategies, profitability, land condition, climate forecasts, simulation models ImplicationsEvidence from northern Australia suggests that managers should apply a form of constrained flexible stocking with upper limits to stocking rate of about 20% to 40% above long-term carrying capacity. Stocking rates should be tactically adjusted on the basis of forage availability, and where appropriate, informed by seasonal climate forecasts. Even in the best years, annual stocking rate increases should be limited to 10% to 20% in order to avoid overstocking in the event of poor subsequent seasons....

show abstract

Section: Strategic Management Of Stocking Ratesmentioning

confidence: 99%

Sustainable management for rangelands in a variable climate: evidence and insights from northern Australia

O’Reagain¹,

Scanlan²

2013

Animal

View full text Add to dashboard Cite

show abstract

“…This approach has also been tested in the Victoria River District (VRD) of the Northern Territory (NT) by Cobiac (2007), Cowley et al (2008) and Hamilton et al (2008). In this region, it was important to correctly account for the area grazed based on watering points.…”

Section: Calculation Of Livestock Carrying Capacity and Forage Producmentioning

confidence: 99%

Climate change impacts on northern Australian rangeland livestock carrying capacity: a review of issues

McKeon¹,

Stone²,

Syktus³

et al. 2009

Rangel. J.

Self Cite

203

136

View full text Add to dashboard Cite

Grazing is a major land use in Australia’s rangelands. The ‘safe’ livestock carrying capacity (LCC) required to maintain resource condition is strongly dependent on climate. We reviewed: the approaches for quantifying LCC; current trends in climate and their effect on components of the grazing system; implications of the ‘best estimates’ of climate change projections for LCC; the agreement and disagreement between the current trends and projections; and the adequacy of current models of forage production in simulating the impact of climate change. We report the results of a sensitivity study of climate change impacts on forage production across the rangelands, and we discuss the more general issues facing grazing enterprises associated with climate change, such as ‘known uncertainties’ and adaptation responses (e.g. use of climate risk assessment). We found that the method of quantifying LCC from a combination of estimates (simulations) of long-term (>30 years) forage production and successful grazier experience has been well tested across northern Australian rangelands with different climatic regions. This methodology provides a sound base for the assessment of climate change impacts, even though there are many identified gaps in knowledge. The evaluation of current trends indicated substantial differences in the trends of annual rainfall (and simulated forage production) across Australian rangelands with general increases in most of western Australian rangelands (including northern regions of the Northern Territory) and decreases in eastern Australian rangelands and south-western Western Australia. Some of the projected changes in rainfall and temperature appear small compared with year-to-year variability. Nevertheless, the impacts on rangeland production systems are expected to be important in terms of required managerial and enterprise adaptations. Some important aspects of climate systems science remain unresolved, and we suggest that a risk-averse approach to rangeland management, based on the ‘best estimate’ projections, in combination with appropriate responses to short-term (1–5 years) climate variability, would reduce the risk of resource degradation. Climate change projections – including changes in rainfall, temperature, carbon dioxide and other climatic variables – if realised, are likely to affect forage and animal production, and ecosystem functioning. The major known uncertainties in quantifying climate change impacts are: (i) carbon dioxide effects on forage production, quality, nutrient cycling and competition between life forms (e.g. grass, shrubs and trees); and (ii) the future role of woody plants including effects of fire, climatic extremes and management for carbon storage. In a simple example of simulating climate change impacts on forage production, we found that increased temperature (3°C) was likely to result in a decrease in forage production for most rangeland locations (e.g. –21% calculated as an unweighted average across 90 locations). The increase in temperature exacerbated or reduced the effects of a 10% decrease/increase in rainfall respectively (–33% or –9%). Estimates of the beneficial effects of increased CO2 (from 350 to 650 ppm) on forage production and water use efficiency indicated enhanced forage production (+26%). The increase was approximately equivalent to the decline in forage production associated with a 3°C temperature increase. The large magnitude of these opposing effects emphasised the importance of the uncertainties in quantifying the impacts of these components of climate change. We anticipate decreases in LCC given that the ‘best estimate’ of climate change across the rangelands is for a decline (or little change) in rainfall and an increase in temperature. As a consequence, we suggest that public policy have regard for: the implications for livestock enterprises, regional communities, potential resource damage, animal welfare and human distress. However, the capability to quantify these warnings is yet to be developed and this important task remains as a challenge for rangeland and climate systems science.

show abstract

“…Carrying capacity estimates for all pastoral leases in the southern rangelands have been compiled by land administration authorities on the basis of a range of methods (e.g. Condon 1968;Condon et al 1969;Johnston et al 1996aJohnston et al , 1996bHamilton et al 2008), but often do not reflect the current condition of the property. In practice, it may be necessary for landholders to develop their own estimate of carrying capacity on the basis of historical stock records, a critical assessment of the condition of the land that has resulted from historical management, and any other local knowledge available.…”

Section: Key Issues Principles and Guidelines For Sustainable Pastora...mentioning

confidence: 99%

Prospects for sustainable use of the pastoral areas of Australia’s southern rangelands: a synthesis

Hacker

McDonald²

2021

Rangeland J.

View full text Add to dashboard Cite

There is growing recognition of the need to achieve land use across the southern Australian rangelands that accommodates changing societal preferences and ensures the capacity of future generations to satisfy their own preferences. This paper considers the prospects for sustainable use of the pastoral lands based either on continued grazing or emerging, alternative land uses. After an overview of the southern rangelands environment, the status of the pastoral industry, its environmental impacts, and key issues for pastoral management, we propose four principles and 19 associated guidelines for sustainable pastoralism. Although some continued withdrawal of land from pastoralism is anticipated, we expect that pastoralism will continue throughout much of the region currently grazed, particularly in the higher rainfall environments in the east. Within these areas, sustainable pastoral land use should be achievable by the application of four broad management principles, as follows: (1) manage grazing within a risk management framework based on the concept of tactical grazing, (2) develop infrastructure to allow best management of both domestic and non-domestic grazing pressure, (3) incorporate management of invasive native scrub, where required, into overall, ongoing property management and (4) manage grazing to enhance biodiversity conservation at landscape scale. Application of these principles and guidelines will require the development of appropriate policy settings, particularly in relation to kangaroo management, climate change, and natural resource governance, together with innovative approaches to research, development and extension. Policy development will also be required if the new industry of carbon sequestration is to deliver socio-ecological benefits without perverse outcomes. Other emerging industries based on renewable energy or ecosystem services appear to have considerable potential, with little risk of adverse ecological consequences.

show abstract

Contemporary livestock carrying capacities for pastoral properties in Northern Australia: a methodology for integrating objective data on pasture growth and condition

Cited by 4 publications

References 8 publications

Sustainable management for rangelands in a variable climate: evidence and insights from northern Australia

Sustainable management for rangelands in a variable climate: evidence and insights from northern Australia

Climate change impacts on northern Australian rangeland livestock carrying capacity: a review of issues

Prospects for sustainable use of the pastoral areas of Australia’s southern rangelands: a synthesis

Contact Info

Product

Resources

About