Black Rat (Rattus rattus). Credit: liftarn

By Rich Bowden:

An experiment to re-introduce eradicated native bush rats to the Sydney region is underway in an attempt to reduce the city’s black rats from bushland.

The native rats were caught up in a campaign instigated by the then Government at the beginning of the 20th century to remove black rats from the Sydney harbourside as a measure to reduce an epidemic affecting the city. The plague, part of a global pandemic which affected a number of countries between 1850 and 1912, was spread by disease-carrying fleas on the black rats and claimed 163 lives between 1900 and 1905, says a University of Sydney news release.

Harmless rodents such as the bush rat and water were caught up in the eradication campaign.

“Historical records and photographs suggest that harmless rodents such as water rats and the native bush rats were caught up in the culling of black rats,” says Dr Banks. “Land-clearing for the suburbs of Mosman, Cremorne and Manly then isolated bush patches on harbour foreshores, depriving the native rodents to recolonise bushland habitats. As a consequence, native bush rats have been a rarity in Sydney ever since – the last confirmed sighting in the city was in 1901.”

Interested in writing on this category for theangle.org? Contact us via our online form.

However researchers are now looking at a program to reintroduce the native rat in a bid to push out the fearsome black rats from local bushland. Researchers believe the native rats will recolonise the bushland at the expense of the black rat, with benefits for many local species such as native birds whose eggs are regularly taken by the black rats.

The team will aim to trap 70 per cent of the vermin rats in four Mosman and Cremorne areas before releasing bush rats in these areas from 2011, says the university. If successful, the program will be expanded across the city’s harbourside.

The initiative is led by UNSW and Sydney University scientists supported by the NSW Department of Environment and Climate Change, NSW National Parks and Wildlife Service, Taronga Conservation Society Australia, Mosman Municipal Council, Australian Wildlife Conservancy, Landcare Research and Rentokil Initial Pty Ltd.

Tags: black rat sydney, native rat, rattus rattus, university of Sydney