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Context. Fauna translocations arc a tool for improving the conservation status of threatened species. Reviews of translocations undertaken in Australia and globally have reported that many fail because of predation by exotic predators. The outcome of similar to 40% of translocations was unknown, often owing to inadequate post-release monitoring. Monitoring methods such as global positioning system data-loggers can provide valuable information on survival, habitat use and sociality, and can be particularly useful for cryptic species.

Aims. The present study used global positioning system (GPS) data-loggers and VHF radio-transmitters to evaluate the success of a reintroduction of the tammar wallaby and measured survival, short-term home-range, habitat use and proximity between reintroduced individuals (as a proxy for association).

Methods. Sixty-nine tammar wallabies of captive and wild stock were reintroduced to Kalbarri National Park (KNP) following long-term and broad-scale fox control, with nine receiving GPS data-loggers, and 16 receiving VHF radio-transmitters. Wallabies were intensively monitored for up to 11 months post-release. Mortalities were investigated using DNA identification and field necropsies.

Key results. In total, 16 of the 25 collared wallabies died within 11-319 days of release. Ten of the sixteen deaths were from predation. Home-range areas were larger than those reported elsewhere. Wallabies utilised long-undisturbed vegetation with a dense canopy cover during crepuscular periods. These areas were likely sought as refuge from predation and thermal extremes. During the main feeding period, a mosaic of recently burnt (i.e. similar to 1 year) and >10 years since last disturbance was important.

Conclusions. The reintroduction was not considered successful because two-thirds of the collared wallabies died within 1 year of release and, therefore, the success criteria were not met.