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Rangelands support many ecosystem services important to humans, including climate regulation. They also have a significant role to play in the mitigation of greenhouse gases. However, the capacity of any rangeland to do this depends foremost upon the condition of biodiversity, and the functioning of its ecosystems. Considerable research has been undertaken on rangeland condition but it has not yet included the assessment of biodiversity (plants, animals and microbes) as a primary focus. Rangeland managers have struggled to assess biodiversity condition because it is rarely defined, is everywhere (so what do you assess?), is always changing in response to natural and human disturbances (so how do you know when it has changed?) and what amount signals management action. Here we present a framework that addresses these issues, and apply it to select surrogates and indicators that are scientifically defensible in biological and planning terms for assessing biodiversity. An arid Australian rangeland region is used as a case study to develop and apply our approach. We were not able to illustrate interpretation of condition because of the absence of long-term monitoring data in Australian rangelands, but we do provide guiding principles about sampling design and analytical methods for interpretation that use raw data rather than multimetrics. We discovered that different management outcomes expected to be informed from assessing biodiversity condition affected surrogate and indicator choice, and that a number indicators were not robust when assessed on conceptual relevance, measurement qualities, feasibility of implementation and policy and management relevance for four different management outcomes. Our work highlights the importance of stating the expected outcomes of biodiversity condition assessments up front, so that indicators relevant to future management are chosen. It also shows that critical thought on the robustness of indicators is warranted, especially as condition assessments under climate change will require information on the functional traits of species. We conclude by assessing the strengths and weaknesses of our framework in relation to environmental planning.

Beef cattle production is the major agricultural pursuit in the arid rangelands of Australia. Dingo predation is often considered a significant threat to production in rangeland beef herds, but there is a need for improved understanding of the effects of dingo baiting on reproductive wastage. We experimentally compared fetal/calf loss on baited and non-baited treatment areas within three northern South Australian beef herds over a 2–4-year period. At re-musters, lactation was used to determine the outcomes of known pregnancies. Potential explanatory factors for fetal/calf loss (dingo baiting, dingo activity, summer heat, cow age, seasonal conditions, activity of dingo prey and selected livestock diseases) were investigated. From 3145 tracked pregnancies, fetal/calf loss averaged 18.6%, with no overall significant effect of baiting. Fetal/calf loss averaged 27.3% for primiparous (first pregnancy) heifers and 16.8% for multiparous (2nd or later calf) cows. On average, dingo-activity indices were 59.3% lower in baited treatments than in controls, although background site differences in habitat, weather and previous dingo control could have contributed to these lower indices. The overall scale and timing of fetal/calf loss was not correlated with dingo activity, time of year, a satellite-derived measure of landscape greenness (normalised difference vegetation index), or activity of alternative dingo prey. Limited blood testing suggested that successful pregnancy outcomes, especially in primiparous heifers, may have been reduced by the livestock diseases pestivirus and leptospirosis. The percentage occurrence of cattle hair in dingo scats was higher when seasonal conditions were poorer and alternative prey less common, but lack of association between fetal/calf loss and normalised difference vegetation index suggests that carrion feeding, rather than calf predation, was the more likely cause. Nevertheless, during the fair to excellent prevailing seasons, there were direct observations of calf predation. It is likely that ground baiting, as applied, was ineffective in protecting calves, or that site effects, variable cow age and disease confounded our results.

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