Retrospective monitoring of rangeland vegetation change: ecohistory from deposits of sheep dung associated with shearing sheds

This paper explores the potential of a new method of reconstructing histori cal vegetation change in the Australian rangelands. Historical monitoring o f rangeland vegetation has been so deficient that it is not possible to det ermine whether a long-term trend toward degradation has occurred (as is oft en assumed) or, indeed, if it is continuing to occur. Because long-term rec ords are unavailable any attempt to monitor vegetation retrospectively must be based on proxy measures rather than direct observation. Where historica l data are lacking an integration of palaeoecological, archaeological and e cological methods is required to reconstruct the past. Our research is base d on a detailed analysis of sheep faeces deposited near a shearing shed in the semiarid rangelands of south-west Queensland between the late 1930s and the mid-1990s. The faeces in these deposits represent the diet of sheep in the days leading up to the property's annual shearing and as such are a po tentially useful index to changes in vegetation. Results indicate significa nt changes in the diet of sheer since the late 1940s. The potential of this method, and its limitations, are discussed. Long-term records are critical in understanding issues of sustainability in land management and it is int ended that this paper will stimulate further research into historical veget ation change in rangelands.