habitat_narrative
Terrestrial
Generally, Rhabdomys species have a wide habitat tolerance, and are commensal species occasionally found in agricultural lands and in houses, and are sometimes considered pests. For example, they ring-bark young Pinus saplings (Monadjem et al. 2015). Rhabdomys were sampled in grasslands (wet and dry), Kikuyu (Pennisetum clandestinum) pastures and disturbed grasslands in Umvoti Vlei Conservancy, KwaZulu-Natal Province (Fuller & Perrin 2001). The three proposed arid-adapted species within what is currently regarded as the xeric R. pumilio clades appear to be specific to different biomes (du Toit et al. 2012). Rhabdomys pumilio occurs in the Fynbos and Succulent Karoo Biomes; R. intermedius occurs within the Nama-Karoo Biome; and R. bechuanae occurs within the Nama-Karoo and Savanna Biomes, with its distribution towards the east being restricted by an increase in annual rainfall. Rhabdomys dilectus favours mesic habitats within the Grassland and Savanna Biomes, and relies strongly on ground cover (Ganem et al. 2012, Meynard et al. 2012, Dufour et al. 2015). For R. dilectus and R. intermedius only, overstocking in agricultural areas, and the reduction of grassland cover is likely to negatively impact the survival success and distributional range of these species.Rhabdomys are diurnal and crepuscular omnivores with a diet of seeds, fruits, green plant material, Acacia pods, Protea flower bracts, Pinus bark and arthropods (Fuller and Perrin 2001, Skinner and Chimimba 2005, Monadjem et al. 2015). They are primarily granivorous, but depending on the season, are known to be opportunistically omnivorous, occasionally consuming insects (Perrin and Curtis 1980). Research suggests that the mesic-adapted R. dilectus is mostly solitary whereas the more arid-adapted species appear to be more communal (Schradin and Pillay 2005). The genus as a whole has been frequently described as a niche generalist. The four proposed species, however, appear to present different niche requirements, some of them appearing as specialists (du Toit et al. 2012, Meynard et al. 2012). Ecological niche modelling supports the separation of the xeric and the mesic species along a precipitation and temperature gradient from east to west (du Toit et al. 2012, Meynard et al. 2012). The breeding season of the Four-striped Grass Mouse commences in August (Schradin and Pillay 2005), and terminates at the start of November in the Succulent Karoo, although extends until March/April in other parts of their range, due to spatio-temporal variation in rainfall patterns (Schradin and Pillay 2005). The start of the breeding season is dependent on a combination of food availability, temperature and rainfall (Brooks 1974; Perrin 1980a,b; Rowe-Rowe and Meester 1982). Young are generally born in the summer months between September and April (Smithers and Wilson 1979, Perrin 1980b, Rowe-Rowe and Meester 1982, Nel et al. 1984, David and Jarvis 1985, Wirminghaus and Perrin 1992, Lynch 1994). A mean gestation period of 25.4 days has been suggested (Brooks 1974, 1982). Litter size is affected by female age and body mass, and females produce an average of two (and maximum of five) litters per season (David and Jarvis 1985). Litter size averaged at 4.9 (range, 2–9) on the Cape Flats (David and Jarvis 1985), 5.8 (range, 3–8) in Lesotho (Lynch 1994), 4.6 (range, 3–7) in the Drakensberg (Rowe-Rowe and Meester 1982), 5.9 (range, 2–9) in Gauteng (Brooks 1974), and 6.1 (range, 1–11) in KwaZulu-Natal (Taylor 1998). In the wild, average life expectancy is documented as 1.5 months (David and Jarvis 1985), but individuals may live for up to 24 months in captivity (Brooks 1974).Rhabdomys species are particularly important forage species for diurnal raptors, snakes and small mammals, including Caracal (Caracal caracal), Black-backed Jackal (Canis mesomelas), African Wildcat (Felis silvestris) and several species of mongoose (De Graaf 1997), as they are one of the few diurnal rodent species. Since different species of the complex have different ecological requirements, they may be used as bio-indicators of changes in aridity. Rhabodmys dilectus is thought to rely strongly on water and vegetation cover, unlike R. bechuanae. Additionally, R. pumilio is a pollination agent in the Cape Fynbos.