Christmas Island’s last remaining indigenous mammal, the critically endangered Christmas Island flying-fox (Pteropus natalis melanotis), is a keystone species with a crucial role in pollination and seed dispersal.

The island is also home to several highly threatened species of reptiles, two of which have since become extinct-in-the-wild. Highly successful captive breeding programs were established on Christmas Island and at Taronga Zoo in 2009 and have rescued both species from extinction, and reintroductions are currently underway in predator-proof “soft release” sites on the island.

These programs are designed to advance our knowledge of the biology and health of Christmas Island’s endemic threatened species, and to better understand the factors contributing to both species and ecosystem health toward providing science-based advice for successful recovery plans. 

The Registry team, with collaborators at Sydney University, recently discovered a new bacterium causing severe and uniformly fatal infections in four lizard species on the island. The identification of this organism on Christmas Island highlights the importance of Taronga’s insurance captive population in securing species survival.  The Registry’s research has informed the development of biosecurity advice to raise awareness and attempt to prevent this pathogen from reaching mainland Australia where it poses a considerable threat to herpetological biodiversity.