Ochotona pusilla (Pallas, 1769)

Don E. Wilson, Thomas E. Lacher, Jr & Russell A. Mittermeier, 2016, Ochotonidae, Handbook of the Mammals of the World – Volume 6 Lagomorphs and Rodents I, Barcelona: Lynx Edicions, pp. 28-43 : 39-40

19.

Steppe Pika

Ochotona pusilla

French: Pika des steppes / German: Steppenpfeifhase / Spanish: Pica de estepa

Other common names: Little Pika

Taxonomy. Lepus pusillus Pallas, 1769 ,

“in campis circa Volgam” (= in plains along Volga). Restricted by Chaworth-Musters in 1933 to “neighbourhood of Samara.”

According mtDNA and nDNA, O. pusilla belongs to subgenus Lagotona, which is the sister taxon to subgenus Pika. Various fossil forms belonging to subgenus Lagotona are known mainly from eastern European Pleistocene sediments. In the Holocene, distribution of O. pusilla in Europe contracted along with cold glacial steppes. J. R. Ellerman and T. C. S. Morrison-Scott synonymized O. nubrica and O. forrest: with this species, but subsequent studies did not support this point of view. According to morphological study, O. pusilla includes angustifrons and also minutus as ajunior objective synonym of Lepus pusillus . Traditionally, European and Asian parts of the distribution are listed as separate subspecies, but neither morphological nor mtDNA variation supports the existence of two taxa. Monotypic.

Distribution. Steppe belt from Obshchy Syrt Plateau, S of the Ural Mts and Mugodzhar Hills, E to W foothills of Altai Mts in Russia and Kazakhstan.

Descriptive notes. Head-body 150-210 mm, ear 17-22 mm, hindfoot 25-31 mm; weight 95-270 g. The Steppe Pika is medium-sized. Dorsalfur is grayish brown, mixed with white hair tips. Ventral fur is light gray. Winter fur is longer, softer, and lighter than during other seasons. Ears are rounded, rufous inside, chocolate brown at edges with white margins. Skull is medium-sized, short, and stout, with incisive and palatal foramens separated. Auditory bullae are medium-sized. Condylobasal lengths are 33-39 mm, skull width are 18-21 mm, and skull heights are 14-15 mm. Steppe Pikas are smaller and darker than Kazakh Pikas ( O. opaca ) and lack rufous pelage color, in contrast to Alpine Pikas ( O. alpina ). Compared with the Northern Pika ( O. hyperborea ), the Steppe Pika has bigger orbit and higher mandible.

Habitat. Lowland shrub steppe and semi-desert. The Steppe Pika is a burrowing species that digs mainly at the base of a bush and prefers shrubby and stony landscapes. In different parts of its distribution,it is associated with different species of shrubs: e.g. dwarf almond ( Prunus ) and spiraea ( Spiraea ), both Rosaceae .

Food and Feeding. The Steppe Pika feeds on green plants, mainly herbs and shrubs, and stores hay in hay piles, beginning in mid-summer but earlier in the eastern part of its distribution. Hay piles are 300-7000 g. Each hay pile consists of one or more dominant plant species. Individual Steppe Pikas can prefer different plant species. Hay piles are usually situated under some cover such as a bush or stone. During cold periods, Steppe Pikas eat hoarded hay but also actively feed on dry vegetation.

Breeding. Breeding of Steppe Pikasstarts in April and lasts 2-4 months depending on region. Young females become fertile 4-5 weeks after birth and breed. Males are not known to breed in the year of their birth. Each female has 3-13 embryos and can give birth to 27-36 young/season. Gestation is 22-24 days; neonates are bare and born with their eyes closed; they weigh 6-7 g. Fur appears on the second day; eyes open on the eighth day. Lactation lasts 20-21 days. Postnatal mortality of Steppe Pikasis very high; only ¢.25% of neonates survives the first month.

Activity patterns. Activity patterns of Steppe Pikas change seasonally and can be traced by loud vocalization. Steppe Pikas can be active throughout the day but avoid midday heat and windy periods. They are most active at dusk and first part of the night. Diurnal activity is characteristic only in spring. The Steppe Pika tends to be secretive;it is usually only heard vocalizing or seen for a few seconds. It probably spends most time inside burrows; amount of time spent aboveground is shorter in the western part ofits distribution.

Movements, Home range and Social organization. Steppe Pikas move fast and dash under cover of vegetation or rocks. Home ranges are 80-300 m?, depending on habitat. Densities are 1000-8000 ind/km?. On edges of its distribution and in suboptimal habitats, Steppe Pikas are solitary, with densities below 100 ind/km?. Areas occupied have well-marked trails and piles of pellets, either in latrines (in eastern part of distribution) or scattered irregularly (western part). A Steppe Pika “marks” its home range with loud calls, or “songs,” that can be heard from 1-2 km. When calling, a Steppe Pika sits on its hindfeet and turnsits head upward. Steppe Pikas dig temporary and breeding burrows. Temporary burrow is short (less than 2 m) and shallow. Breeding burrow has several branches and breeding chambers; it opens with 1-5 entrances. Depth is 20-50 cm, and size is c.1-5 m*. In winter, Steppe Pikas live under snow but above the ground’s surface in spherical nests made of dry vegetation.

Status and Conservation. Classified as Least Concern on The [UCN Red List. In the 18" century, the Steppe Pika was found on the western side of the Volga River, but it disappeared from this area in the 19" century. Numbers of Steppe Pikas also decreased in the Volga region. Expanded agricultural activities were probably responsible for this distributional contraction. Modern occurrence of the Steppe Pika in the European part of its distribution—formerly considered a unique subspecies, O. p. pusilla —is confined to thickets between agricultural lands, and as a separate subspecies, it was classified as Vulnerable on The IUCN Red List. Conservation status is secure because existence of separate European subspecies was not confirmed by special study and the Asian population is numerous and widespread.

Bibliography. Chaworth-Musters (1933), Ellerman & Morrison-Scott (1951), Melo-Ferreira et al. (2015), Nikol'skii et al. (2000), Ognev (1940), Rybakova (2007), Rybakova et al. (2003), Shubin (1965), Sludskiy et al. (1980), Sokolov et al. (1994).

Figures

15. Kazakh Pika (Ochotona opaca), 16. Silver Pika (Ochotona argentata), 17. American Pika (Ochotona princeps), 18. Collared Pika (Ochotona collaris), 19. Steppe Pika (Ochotona pusilla), 20. Large-eared Pika (Ochotona macrotis), 21. Royle’s Pika (Ochotona roylu), 22. Afghan Pika (Ochotona rufescens), 23. Forrest's Pika (Ochotona forrest), 24. Ladak Pika (Ochotona ladacensis), 25. Turkestan Red Pika (Ochotona rutila), 26. Kozlov’s Pika (Ochotona koslowi), 27. Chinese Red Pika (Ochotona erythrotis), 28. Glover’s Pika (Ochotona gloveri), 29. Ili Pika (Ochotona iliensis)

Distribution. Steppe belt from Obshchy Syrt Plateau, S of the Ural Mts and Mugodzhar Hills, E to W foothills of Altai Mts in Russia and Kazakhstan.