The bush Karoo ratOtomys unisulcatuson the Cape West coast

Pup retrieval in the African bush Karoo rat

“…Mouth-carrying in O. unisulcatus apparently reflects the nesting habits of the species, as outlined below: O. unisulcatus is unique among the otomyines in that it constructs a twig lodge, which may have a volume in excess of 1 m3, within or beneath which the nest is constructed (Vermeulen and Nel 1988, Brown and Willan 1991, Kerley and Erasmus 1991. Prototomys, the Pliocene ancestor of the modern Otomyinae (Pocock 1976) was probably mesically adapted (Taylor et al 1989), occupying densely vegetated habi tats and nesting on the surface (Willan 1990).…”

“…In nature, O. unisulcatus carry sticks and twigs which are used to construct t.ieir lodges (Vermeulen andNel 1988, Kerley andErasmus 1992). Similarly, food is often carried back to the nest and consumed there (Brown andWillan 1991, Kerley andErasmus 1992).…”

Comparative renal morphology of some southern African otomyine rodents

“…unisulcatus (Vermeulen andNel 1988, Brown andWillan 1991) and both Parotomys species (De Graaff 1981, Skinner andSmithers 1990) nest communally in underground burrows. In addition, O. unisulcatus (Vermeulen andNel 1988, Brown andWillan 1991) and P. littledalei (Roberts 1951) construct an insulating lodge above the burrow system.…”

“…For example, the pack rat Neotoma lepida feeds largely on succulent plant material (cactus), and does not have the kidneys extensively modified despite the aridity of its desert habitat (Schmidt-Nielsen 1964). Similarly, all three xerophilic species feed on succulent herbaceous plants when available (Skinner and Smithers 1990, Vermeulen and Nel 1988, Brown and Willan 1991. Furthermore, O. unisulcatus feeds arboreally on the highly hydrated shoots and leaves of shrubs and small trees (Brown and Willan 1991).…”

Reproductive biology of the southern African ice rat

“…O. irroratus is a mesophylic species (Perrin 1981, Willan andHickman 1986) occupying densely vegetated habitats and generally nesting on the surface beneath overhanging vegetation (Davis 1973); the high risk of predation on the young selects for nipple-clinging (Davis and Meester 1981). The arid-adapted O. unisulcatus nests in a twig "lodge" (Vermeulen and Nel 1988) which is an effective deterrent to predators (Brown 1988). The risk of predation on young O. s. robertsi is probably insignificant, as indicated by its nesting habits, delayed emergence of young from the burrow and the low incidence of predators in its habitats.…”