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Summary: Every macropod population is unique in terms of the combination of species, site and management goals, so there is no universal 'best' method for surveying populations. We distinguish between different measures of abundance and the confidence a manager can place in them. We examine the separate components of survey methods: the survey platform, mode of detection and form of sampling. We also review the range of current methods available and highlight new developments, including their assumptions and limitations. To guide managers in choosing a method for their management context, we provide a decision matrix based on the behavioural ecology of the target species, the structure of habitat at the site and the porosity of the site boundary. To promote current best practice, we describe in detail four standard counting methods: direct count, sweep count, faecal accumulation rate and distance sampling. [ABSTRACT FROM AUTHOR]

Reference intervals (RIs) describe baseline parameters of healthy animals, providing a powerful tool for wildlife managers to monitor health, identify disease and assess animal welfare. This paper reports haematological, glucose and serum protein RIs for one of Australia's most iconic and managed mammals, the eastern grey kangaroo Macropus giganteus. Blood samples (n = 514) were collected from 11 populations of eastern grey kangaroos, across much of their geographic range. A species-level RI was initially established based on samples collected from four sites (n = 245) and was further partitioned based on significant differences associated with sexual maturity and season. Unique population means were established from a further seven sites to investigate the importance of biotic (sex and sexual maturity) and abiotic (season, site, rainfall, temperature and laboratory) factors on kangaroo health parameters. Random forest analysis of health parameters revealed that abiotic factors (site, rainfall, temperature and season) were largely responsible for differences in haematological, glucose and serum protein values. Sex was found to have no influence, while sexual maturity and laboratory of analysis had moderate effects. Based on these findings, interpretation of individual and population haematological and serum protein values requires careful consideration of the timing of sample collection, environmental conditions and sexual maturity. When assessing kangaroo health, the relevant sexual maturity RI must be considered initially. For populations with similarities to those described (for example high density or captive populations) users should also consider site specific mean haematological and serum protein values. The RIs reported are valuable when establishing the health status of kangaroo populations. Furthermore, understanding the influence of biotic and abiotic factors will improve the utility of these RIs to assess health, disease status and improve welfare in eastern grey kangaroos. [ABSTRACT FROM AUTHOR]