Livestock performance in a varied landscape and climate

The sheep and beef industries are significant contributors to Victoria’s economy. Despite competition for land and water resources and an increasingly variable climate, these industries need to continue to increase productivity to remain profitable. As major contributors of greenhouse gases, particularly methane, reducing emissions is also a challenge for these enterprises when considering alternative food and fibre sources. Financial benchmarking, modelling and emission intensity studies seldom recognise that these enterprises are often grazed on diverse landscapes and in the most variable climates, where options for alternative food production are limited. The co-production of meat and fibre from most sheep breeds is often not well recognised and consistently attributed in greenhouse gas emission allocation. This study aimed to investigate whether the relative profitability of a range of sheep and beef enterprises, change across land class and climate. It also aimed to develop measures of and to provide insight into drivers of flexibility, efficiency and profitability leading to guidance on better placed enterprise choice for environment. Four farm case studies were selected to represent climate and land class variability and modelled in GrassGroTM. Each farm had one to three land classes enabling eleven ‘farms’ differing in land class over four locations to be simulated. Diversity of land class in this study represented differences in soil type, depth and fertility, slope of land and pasture species. A range of sheep and beef enterprises were tested across all farms to enable comparisons of profitability, flexibility and enteric methane emissions over a forty year period (1970-2010). Enterprise profitability was estimated as net margin per hectare, to allow for labour requirement differences between the enterprises. Flexibility was explored by considering enterprise profit variability and profit response in the top and bottom 10% of years. Strategies that reduced the effects of poor years (higher profit) and increased or did not reduce profitability in good years were considered to have greater flexibility. Enteric methane emissions were calculated in GrassGroTM and an estimation of total end-product made to address the differences in processing stages of red meat and wool, and provide a measure of emission intensity. To further consider the effects of droughts, studies were conducted to quantify commodity price changes in droughts and early warning indicators. A model using total soil water and the Southern Oscillation Index was tested to investigate the potential for predicting droughts before the onset of spring and so provide opportunity for early decision making to mitigate some of the financial impacts of droughts. Wool contributed most to enterprise profitability when pasture production was lowest, as on unimproved pastures, poor soil types and/or in low rainfall years. As pasture production increased across sites and was more reliable, live weight was a stronger driver of profit and systems that had a high proportion of immature animals, tended to perform the best. The specialist meat sheep enterprises were the most profitable when pasture production was highest, but had the highest sensitivity to climate variability. The spring calving enterprise tested in this study was consistently more profitable than the autumn calving enterprise, although the difference was less when pasture production was lowest. These results support, and help to explain, farm financial analyses that have reported enterprise profitability changes between rainfall or regional zones. Where these results did not reflect modelling studies, it was considered to be due to the range in pasture production at the sites tested in this study, as most of the differences were evident at the extremes in pasture production. Most modelling studies in Victoria use sites with high and reliable rainfall, and/or highly productive pastures. Whilst wool production provided a buffer to the susceptibility to droughts, the ability to increase meat production from the system increased flexibility and enterprise profit. For the prime lamb enterprises, a first cross or self-replacing meat enterprise suited to the climate and land class were equally profitable and