Converting rangelands to reserves: Small mammal and reptile responses 24 years after domestic livestock grazing removal

Abstract

AbstractWith one million species threatened with extinction and more than a third of terrestrial Earth now devoted to crop or livestock production, many conservation organisations are acquiring land, destocking and converting them to national parks or conservation reserves. When pastoral properties are acquired, destocking is often the first management action. Species responses to destocking are varied and largely associated with changes in ground vegetation complexity. However, studies over short timeframes may fail to capture the often slow and episodic recovery post‐destocking, particularly in arid and semi‐arid ecosystems. In this study, we examined the response of small mammals and reptiles between 6 and 24 years since destocking in mallee (Eucalytpussp.) andCasuarinavegetation communities in semi‐arid Australia. As casuarina sites were closer to water than mallee, they were subject to higher domestic livestock grazing intensity, and higher grazing pressure from invasive goats and native kangaroos after livestock were removed. We related faunal abundance and diversity to time‐since‐destocking, fractional cover, rainfall and temperature and described compositional dynamics. We found that the vegetation types had distinct fauna communities and unique recovery trajectories. In mallee, reptile abundance and diversity increased with time‐since‐destocking but did not change in casuarina. Small mammal response to time‐since‐destocking was non‐linear and strongly influenced by rainfall. Overall, the mallee community showed signs of recovery, but recovery was less evident in the more degraded casuarina. We highlight that destocking ex‐pastoral properties is rarely a restoration ‘quick‐fix’ and land managers must deal with a complex legacy of impacts, when converting pastoral land to conservation reserves.