National recovery plan for the Golden Bandicoot Isoodon auratus and Golden-backed Tree-rat Mesembriomys macrurus 2004 - 2009
Palmer, C. Taylor, R. and Burbidge, A.
Northern Territory Department of Infrastructure, Planning and Environment, 2003
ISBN: 190277226X
Conservation status
Golden Bandicoot
The conservation status of the Golden Bandicoot (Isoodon auratus) varies across jurisdictions and is classified as:
- Nationally both subspecies, I. auratus barrowensis and I. auratus auratus, are listed as Vulnerable under the Environment Protection and Biodiversity Conservation Act 1999
- Northern Territory - Endangered under the Northern Territory Parks and Wildlife Conservation Act 2000
- Western Australia Schedule 1 (Fauna that is rare or likely to become extinct), Western Australia Wildlife Conservation (Specially protected fauna) Notice 2003, ranked as Vulnerable by the WA Threatened Species Scientific Committee
- South Australia - Endangered in Schedule 7, Part 1 of the National Parks and Wildlife Act 1972 South Australia
- New South Wales Species presumed Extinct, Part 4 Threatened Species Conservation Act 1995 No.101
The listing at the national level has no associated documentation as to what IUCN categories the species qualifies under. Under version 3.1 of the International Union for the Conservation of Nature (IUCN) Red List Categories it does not qualify under the extent of population or range reduction as the reductions, although massive, occurred longer ago than the 10 years specified under the categories. It appears that the species declined from its former distribution by the early 20th Century (Lee 1995). It can be considered under criteria B as its area of occupancy is less than 2000 km2 (see below). Under B2 it qualifies for criteria a (known to exist at no more than 10 locations, treating the whole of an island as one location). However, it also needs to qualify under another criteria to be considered as Vulnerable. Under criteria b a continuing decline in population or range is required. Recent surveys suggest that there has been no range decline in the north Kimberley since the first extensive surveys of that area in the 1970s (Tony Start pers comm.) There is no evidence of population declines in the island populations. However it is unknown as to whether populations on the mainland are still declining. If a precautionary approach is adopted the possibility of a continuing population decline on the mainland would qualify the species as Vulnerable under criteria B2ab(v).
In the Northern Territory it is classified as Endangered under criteria B1ab (I,ii,iii,iv,v); C2a(i) of version 3.1 of the IUCN Red List Categories IUCN deals with taxa globally not taxa jurisdiction data. Nevertheless to facilitate prioritising actions within the NT, IUCN criteria has been applied.:
- Extent of occurrence estimated to be <5,000 km2
- Population size estimated to number <2,500 mature individuals
- Severely fragmented or known to exist at no more than five locations
- A continuing decline, observed, projected or inferred
- No sub-population estimated to contain more than 250 mature individuals
Golden-backed Tree-rat
The Golden-backed Tree-rat is listed as:
- Nationally - Vulnerable under the Environment Protection and Biodiversity Conservation Act 1999
- Northern Territory - Endangered under the Northern Territory Parks and Wildlife Conservation Act 2000
- Not considered threatened under Western Australian legislation.
The listing at the national level has no associated documentation as to what IUCN categories the species qualifies under. Under version 3.1 of the IUCN Red List Categories it does not qualify under the extent of population or range reduction as the reductions, although large, occurred longer ago than the 10 years specified under the categories. There appears to be no reduction in its present range on the mainland (in the northern Kimberley) since the 1970s (see below). It can be considered under criteria B as its area of occupancy is less than 2000 km2 (see below).
Under B2 it qualifies for criteria a (known to exist at no more than 10 locations, treating the whole of an island as one location). However it also needs to qualify under another criteria to be considered as Vulnerable. Under criteria b a continuing decline in population or range is required. Recent surveys suggest that there has been no range decline in the north Kimberley since the first extensive surveys of that area in the 1970s (Tony Start, pers comm.) However it is unknown as to whether populations on the mainland are still declining. If a precautionary approach is adopted the possibility of a continuing population decline on the mainland would qualify the species as Vulnerable under criteria B2ab(v).
In the NT it is classified as Endangered (under criteria B1ab(I,ii,iii,iv,v); C2a(i)) based on:
- extent of occurrence estimated to be <5,000 km2
- population size estimated to number <2,500 mature individuals
- severely fragmented or known to exist at no more than five locations
- a continuing decline, observed, projected or inferred and
- no subpopulation estimated to contain more than 250 mature individuals.
However, there is a high level of uncertainty about total population size and extent of occurrence for the Golden-backed Tree-rat. There have been no recordings of the species in the Northern Territory since 1969 despite extensive wildlife surveys including many apparently suitable areas and it is possible the species is no longer present (Woinarski 2002).