Status and conservation of the rodents of Victoria

Nineteen species of rodents, in two families, have been recorded from Victo ria in the modern era. Eighteen are of the family Muridae, represented by 1 5 native and 3 introduced species. The other species, now extinct in Victor ia, was the introduced Sciurus carolinensis. Six of the native species are extinct, one is classified Critically Endangered, one Endangered and four L ower Risk near threatened. Four of the extinct species were restricted to t he semi-arid far north-west; these were Leporillus apicalis, L. conditor, P seudomys bolami and P. desertor. The two other extinct species, Conilurus a lbipes and Pseudomys australis, inhabited open forest/woodland, and grassy ecosystems. Extant species include Rattus fuscipes and R. lutreolus, both i n the sub-family Murinae; both are widespread and common, particularly in s outhern Victoria. The remaining seven species are in the sub-family Hydromy inae. Hydromys chrysogaster is widespread in waterbodies throughout the sta te. Notomys mitchellii and Pseudomys apodemoides occur in dry habitats in t he north-west of Victoria; they are uncommon, but most of their habitat is reserved. Mastacomys fuscus, found in higher-rainfall areas of southern and eastern Victoria, from coastal dunes to alpine snowfields, is uncommon. Th e distribution of Pseudomys fumeus is disjunct, in four widely separated ar eas. It is classified as Endangered. P. shortridgei is restricted to the Gr ampians and south-western Victoria, where it may be locally common. The mos t geographically restricted rodent species in Victoria, Pseudomys novaeholl andiae, is Critically Endangered and is the subject of special conservation measures. The most critical threats to rodent populations in Victoria are considered to be (1) the lack of active habitat management for those specie s that require early seral stages in vegetation, (2) predation by introduce d carnivores, and (3) the fragmentation of species into small genetically i solated populations.