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Wagner's Gerbil

Gerbillus dasyurus

French: Gerbille de Wagner / German: \WagnerRennmaus / Spanish: Gerbillo de Wagner

Other common names: Rough-tailed Gerbil, Wadi Hof Gerbil, Wagner's Dipodil

Taxonomy. Meriones dasyurus Wagner, 1842,

Sinai, Egypt.

D. L. Harrison and P. J. J. Bates undertook a revision of this taxon in 1991, but in 2005 G. G. Musser and M. D. Carleton placed it in the genus Dipodillus . Monotypic.

Distribution. S Turkey, Syria, Lebanon, Israel, Palestine, Jordan, Egypt (Sinai), Iraq, and Arabian Peninsula.

Descriptive notes. Head-body 70-110 mm, tail 85-140 mm, ear 9-16 mm, hindfoot 20-27 mm; weight 15-35 g. In Turkey, male Wagner's Gerbils are significantly smaller in head-body length but heavier in weight than females. Medium-sized gerbil with long hairy tail (122-155% of head-body length) terminating in a pencil. Soles of hindfeet are naked. Pelage is long and dense, with pale gray-yellow dorsal color and pure white ventral one. Supraorbital and auricular white patches are present,as is a black eyebrow. Females bear four pairs of mammae. Diploid number 2n = 60 and FN = 66-70.

Habitat. In Arabia, Wagner’s Gerbil is found in steppic zones in deserts and it prefers rocky areas. Limestone escarpments with Rhanterium epapposum ( Asteraceae) and herbs and grasses are also favored. In Yemen it was found in thorn thickets or at the edge of cultivated fields. It may be found on sandstone hills at 500-2000 m in Israel. In Jordan, rocky areas with low vegetation ( Anabasis, Atriplex, Halogeton spp., all Amaranthaceae, and Artemisia, Asteraceae) are preferred and sandysoilis avoided. In Turkey, rocky hills with poorsoil and vegetation are favored. Different habitats were reported for the Negev (southern Israel) population but, similarly, sand dunes were avoided and preference was shown for hills and dry river beds with sandy gravel soils.

Food and Feeding. Wagner's Gerbil is herbivorous, foraging on soil surface for seeds of annual herbs such as Medicago (Fabaceae) and Atriplex, or succulent plants; some insects may be included in diet.

Breeding. Reproduction season of Wagner's Gerbil is long (February—October). Gestation is apparently 18-22 days in Israel and 24-26 days in Saudi Arabia. Females may bear 3-7 embryos, and litters are of 2-7 young (average 4-8) in captivity. Young at birth weigh 1-7 g, and are naked and altricial. First hairs appear at day 5, eyes open at day 22, and young are weaned at day 40.

Activity patterns. Wagner's Gerbil is strictly nocturnal and terrestrial. It digs simple burrows with one tunnel, a chamber, and aeration pits generally located under the bush and closed during day in desert. Tunnel length varies, 0-45-3 m, and average tunnel volume is between 0-29 dm’ and 4-2 dm? in Jordan.

Movements, Home range and Social organization. Density of Wagner's Gerbils fluctuates strongly between years and may be dependent on rainfall patterns. In Negev highlands, population varied from 7-3 ind/ha to 32-3 ind/ha in a preferred habitat and was lower in others (0-2-12 ind/ha). Mean home range in Israel was 10-7 m? for males and 8-9 m® for females. May forage at considerable distance from burrow at night. In captivity, existence of some sociality was reported, with territory-marking, “ceremonial” digging, drumming with hindfeet, and the rubbing of secretions from mid-ventral glands on substrate.

Status and Conservation. Classified as Least Concern according to The IUCN Red List. Quite common. Wagner's Gerbil may be found in some protected areas. Longevity in the wild reaches 2-5 years, compared with more than four years in captivity.

Bibliography. Abu Baker & Amr (2003), Al-Khalili & Delany (1986), Amr (2000), Aulagnier et al. (2009), Bahmanyar & Lay (1975), Fiedler (1973), Happold (2013a), Harrison & Bates (1991), Hatough-Bouran (1990), KryStufek & Vohralik (2009), Lewis et al. (1965), Mendelssohn & Yom-Tov (1999), Musser & Carleton (2005), Qumsiyeh et al. (1986), Shenbrot et al. (1997), Wassif et al. (1969), Yigit et al. (2003), Zahavi & Wahrman (1957).