Charles Darwin collected a Bogul or Native Bush Rat in 1836 when the species is thought to have been abundant. Unfortunately, extermination methods during the plague were less discriminatory and many Boguls were killed along with the disease-carrying Black Rat.
The Black Rat continues to out-compete the Bogul in many areas, resulting in its loss from most of the Sydney area. This has great implications for local biodiversity because the Black Rat carries diseases, grazes on young saplings, and easily climbs trees to eat bird eggs – a combined impact that has affected native birds and the horticultural structure of the area. As a first step towards reintroducing the Bush Rat, this project examined the nature of suppression of Black Rats by Boguls.
A specially designed enclosure was built on a revegetated area of Taronga Zoo and experimental conditions generated to examine competitive behaviour in different circumstances. Certain conditions (natural vegetation with ground cover) appear to favour the Bogul, which is then able to out-compete the Black Rat. This data has formed the basis of a government program that will endeavour to reduce the Black Rat population and allow Boguls to re-establish themselves on the Sydney Harbour foreshore, reduce wildlife disease and increase biodiversity in this area.
As Boguls do not remain in highly urbanised areas, there is no significant threat that they will enter homes or domestic gardens. In fact, it is hoped that by out-competing the Black Rat for natural niches, they may reduce the overall population of Black Rats.