Nesogale dobsoni, Thomas, 1884

Russell A. Mittermeier & Don E. Wilson, 2018, Tenrecidae, Handbook of the Mammals of the World – Volume 8 Insectivores, Sloths and Colugos, Barcelona: Lynx Edicions, pp. 134-172 : 166-167

9.

Dobson’s Shrew Tenrec

Nesogale dobsoni

French: Microgale de Dobson / German: Dobson-Kleintenrek / Spanish: Tenrec musarana de Dobson

Other common names: Dobson's Long-tailed Tenrec

Taxonomy. Microgale dobsoni Thomas, 1884 ,

“Nandésen Forest, Central Bet- sileo,” Madagascar. Restricted by R. D. E. MacPhee in 1987 to “perhaps the isolated patch of eastern rain forest situated east of Nandihizana village (1340 m), south of Ambositra; Fianarantsoa, Fianarantsoa [Province, Madagascar]; 20°27’S, 47°09’E” and further clarified as “about 20 mi (30 km) SSW of Ambositra.” Further clarified by P. D. Jenkins and colleagues in 1996 to “estimated as 20°50°S 47°10°E.”

Species dobsoni wasinitially placed in the genus Microgale but soon assigned to a new genus, Nesogale , based on skull and dental morphology. It was then reassigned to Microgale before more recently again placed in Nesogale based on morphological and molecular grounds. Nesogale dobsoni and N. talazaci form a clade, which is sister to Microgale . Monotypic.

Distribution. N, Northern and Central highlands, E & SE Madagascar.

Descriptive notes. Head-body 87-116 mm, tail 89-128 mm, ear 15-23 mm, hindfoot 20-27 mm; weight 21-48 g. Dobson’s Shrew Tenrec is large and has marked seasonal variation in body weight. Tail is nearly equal to head-body length. Pelage is soft; dorsum is gray brown to brown; and venter is gray, with buff or reddish buff wash. Head has small eyes and prominent ears that project beyond pelage. Limbs have short hair, usually lighter than dorsum. Tail is brown above and usually paler below;tail fluctuates seasonally in size, becoming distended with accumulated fat reserves as rainy season approaches and gradually decreasing in size as reserves are depleted.

Habitat. Humid and transitional humid to dry forests from sea level to elevations of ¢.2500 m. Dobson’s Shrew Tenrec is somewhat tolerant of disturbance and found in forest edges.

Food and Feeding. Captive Dobson’s Shrew Tenrecs eat species of Orthoptera, frogs, and occasionally species of Annelida. Smaller species of Microgale are eaten when in pitfall traps, including Cowan’s Shrew Tenrec (M. cowani ), the Lesser Long-tailed Shrew Tenrec ( M. longicaudata ), the Greater Long-tailed Shrew Tenrec ( M. principula ), and the Taiva Shrew Tenrec ( M. taiva ). In captivity, prey is detected by scent and hearing and found by digging and nosing among leaflitter and roots on the ground.

Breeding. Little is known about reproduction of Dobson’s Shrew Tenrec in the wild. In captivity, mating occurs in December—August; young are born in February—May; gestation lasts c¢.62 days, and litters have 1-5 young. Young are born naked, with eyes and ears closed. They begin to leave the nest and forage actively for food shortly after their eyes opened at 22-27 days old; nursing continues, but it is not known when weaning occurs. Females have improved thermoregulation during pregnancy, and resting metabolic rates increase significantly throughout pregnancy and lactation.

Activity patterns. Dobson’s Shrew Tenrecs are terrestrial and primarily nocturnal. They store fat in theirtails. Fat reserves start to accumulate in the tail at the onset of austral winter, and the resulting seasonal fluctuation in weight continues in captivity, increasing from May to a maximum in November-December at the start of rainy season and declining until May. Captive individuals maintained in relatively stable conditions had no tendency to enter deep torpor. Seasonal fat accumulation is presumed to be of benefit when food availability is reduced during the dry season.

Movements, Home range and Social organization. Dobson’s Shrew Tenrecs are presumably solitary. In captivity, males introduced in a neutral area tend to avoid each other after initial contact.

Status and Conservation. Classified as Least Concern on The IUCN Red List (as Microgale dobsoni ). Dobson’s Shrew Tenrec has a wide distribution, occurs in many protected areas, and is tolerant of some habitat modification. It is abundant in some areas, so it presumably has a large overall population, which might be decreasing. It faces no major conservation threats, despite ongoing habitat loss in parts of its distribution.

Bibliography. Eisenberg & Gould (1970), Everson et al. (2016), Goodman & Jenkins (1998, 2000), Goodman, Jenkins & Pidgeon (1999), Goodman, Soarimalala et al. (2013), Gould (1965), Jenkins (2003), Jenkins et al. (1996), MacPhee (1987), Olson & Goodman (2003), Salton & Sargis (2008a, 2008b, 2009), Soarimalala & Goodman (2011), Stephenson & Racey (1993b), Stephenson, Racey & Rakotondraparany (1994), Stephenson, Soarimalala & Goodman (2016i).

Figures

1. Lesser Hedgehog Tenrec (Echinops telfairi), 2. Greater Hedgehog Tenrec (Setifer setosus), 3. Tailless Tenrec (Tenrec ecaudatus), 4. Lowland Streaked Tenrec (Hemacenteles semispinosus), 5. Highland Streaked Tenrec (Hemicentetes nigriceps), 6. Large-eared Tenrec (Geogale aurita), 7. Mole-like Rice Tenrec (Oryzorictes hova), 8. Four-toed Rice Tenrec (Oryzorictes tetradactylus), 9. Dobson’s Shrew Tenrec (Nesogale dobsoni), 10. Talazac’s Shrew Tenrec (Nesogale talazact), 11. Montane Shrew Tenrec (Macrogale monticola), 12. Dryad Shrew Tenrec (Microgale dryas), 13. Short-tailed Shrew Tenrec (Microgale brevicaudata), 14. Pygmy Shrew Tenrec (Microgale parvula), 15. Lesser Long-tailed Shrew Tenrec (Mucrogale longicaudata), 16. Drouhard’s Shrew Tenrec (Microgale drouhardi), 17. Taiva Shrew Tenrec (Microgale taiva), 18. Pale Shrew (Tenrec Mucrogalefotsifotsy), 19. Greater Long-tailed Shrew Tenrec (Microgale principula), 20. Cowan's Shrew Tenrec (Microgale cowant), 21. Naked-nosed Shrew Tenrec (Microgale gymnorhyncha), 22. Shrew-toothed Shrew Tenrec (Microgale soricoides), 23. Major's Shrew Tenrec (Microgale major), 24. Gracile Shrew Tenrec (Microgale gracilis), 25. Thomas’s Shrew Tenrec (Microgale thomasi), 26. Grandidier’s Shrew Tenrec (Muicrogale grandidieri), 27. Web-footed Tenrec (Microgale mergulus), 28. Least Shrew Tenrec (Muicrogale pusilla), 29. Dark Shrew (Tenrec Microgalejobihely), 30. Nasolo’s Shrew Tenrec (Microgale nasoloi), 31. Jenkins’s Shrew (Tenrec Microgalejenkinsae)

Distribution. N, Northern and Central highlands, E & SE Madagascar.