To date, most systematic treatments of Ochotona have been based on morphological characteristics; however, morphology often exhibits phenotypic plasticity and convergent evolution. The goal of the Changlin et al. (1997) study was to clarify confusion concerning six species of Chinese pikas through mtDNA restriction-site analysis. Ganzu pikas are often included in Moupin pika species (Ochotona thibetana) because of similarities in pelage color, size, and shape of the skull. Mitochondrial DNA analysis determined that these were in fact two separate species. Changlin et al. (1997) suggest that evolutionary diversification of pikas might be influenced by historical episodes of geologic and climatic changes. During the early Pleistocene the Qinghai-Xizang (Tibet) Plateau was uplifted, which resulted in an ice age, and moutain formation. Northwestern China became drier due to the rain shadow effect caused by the plateau. Therefore, vegetation was significantly altered and isolation of habitats was frequent. All of these events provide good opportunity for diversification and specialization within the genus Ochotona. Recent geological studies show that an ice sheet did not cover the Qinghai-Xizang Plateau during the Quaternary Ice Age. Therefore, ancestral pikas may have been typical of arid, cold adapted steppes, but now are located in steppe, shrub, coniferous forests, and alpine rocks. This suggests that pikas responded to habitat shifts induced by continued uplift of the Qinghai-Xizang Plateau and glacial cycles from the late Pliocene to the Pleistocene through gradual adaptation to new habitats (Changlin et al., 1997).
Ochotona emerged in the fossil record in the late Miocene in central Asia (Changlin et al., 1997).
Ganzu pikas use their vision to remain vigilant for predators. When two littermates are together they often display body contact or play. When two males come close enough to be seen, the two males will often display warning postures and then chase or retreat into respective territories (Jiang and Wang 1991).
Like many other pikas (Ochotona), Ganzu pikas make frequent, sharp calls. There were 4 types of called identified:
Ganzu pikas, like other mammals, also use chemical cues extensively in communicating. Important forms of chemical communication are:
Communication Channels: visual ; tactile ; acoustic ; chemical
Other Communication Modes: choruses ; scent marks
Perception Channels: visual ; tactile ; acoustic ; chemical
Ochotona cansus populations do not appear to be in decline, therefore they are assessed as Least Concern.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
There are no known adverse effects of Ochotona cansus on humans.
Ganzu pikas are important members of their native ecosystems.
Ganzu pikas impact vegetation communities through their grazing and food storage. They may also be important prey for native predators in steppe ecosystems.
Ganzu pikas, like most pikas, are herbivorous, grazing on the grasses and herbaceous plants in their native communities.
Plant Foods: leaves; wood, bark, or stems; flowers
Primary Diet: herbivore (Folivore )
Ganzu pikas (Ochotona cansus) are endemic to China and are located in the Ganzu, Qinghai, and Sichuan provinces.
Biogeographic Regions: palearctic (Native )
Ganzu pikas inhabit alpine shrub habitats, which are part of steppe-meadow environments. Ganzu pikas live in alpine areas where temperatures fall below freezing even during summer nights, with elevations ranging from 2000 to 4000 m (Kenagy and Zheng, 2006). Ganzu pikas are mainly found in shrubby cinquefoil (Dasiphora fruticosa), but avoid dense shrub areas, preferring areas slightly open such as natural mounds created by zokors (Myospalax). These mounds are used to avoid predators, allowing the pikas to see easier and having escape nearby (Jiang and Wang 1991).
Range elevation: 2000 to 4000 m.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: savanna or grassland
No information on longevity of Ganzu pikas was found in the literature. Most pikas live for only a few years, with high first year mortality rates.
The physical morphology of Ganzu pikas is similar to that of Moupin pikas (Ochotona thibetana), and they can be confused in the field. However, Changlin et. al. 1997 suggests that the two species can be identified by the zygomatic arch. Ganzu pikas have narrower zygomatic arches than Moupin pikas.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: sexes alike
Through visual communication, Ganzu pikas are well adapted to predator evasion. Ganzu pikas remain vigilant, especially to aerial predators, and have a set of warning calls to alert others to danger. Warning calls trigger other pikas to respond with more warning calls, maximizing the efficiency of the transmission of danger signals. Buteo hemilasius, Falco cherrug, Mustela eversmanii, and Mustela altaica are the major predators of Ganzu pikas.
Known Predators:
The mating system of Ganzu pikas includes monogamy, polygyny, polyandry, and promiscuous systems. Jiang and Wang, 1991 indicate that Ganzu pikas exhibited a facultative monogamy mating system. Polygynous situations may be common considering the non-uniform distribution of high-quality habitats, male emancipation from parental care, and asynchrony of female estrus.
Mating System: monogamous ; polygynous ; polygynandrous (promiscuous)
Ganzu pikas breed from April to August. They have a gestation period of about 20 days, and a lactation period of about 18 days. The litter size can be anywhere from 3 to 6 young. Ganzu pikas can breed at least 3 times per year, resulting in 9 to 18 young per year. The young are altricial and emerge from the burrow about 10 days after birth. Subadults (pika less than 1 year old) can and have been observed breeding. Males do not care for the young, even in monogamous pairs.
Nests are constructed 2 to 3 hours before parturition, with a size of 15 cm, consisting of dry grass and hair of yak and sheep. Once the babies are born the mother does not come back to the nest except to nurse.
Breeding interval: Ganzu pikas can breed at least 3 times per year.
Breeding season: Breeding occurs from April to August.
Range number of offspring: 3 to 6.
Average gestation period: 20 days.
Average weaning age: 18 days.
Average age at sexual or reproductive maturity (female): 1 years.
Average age at sexual or reproductive maturity (male): 1 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous ; post-partum estrous
Males rarely care for the young. Mother-offspring relationships resemble those of other medium-sized lagomorphs. Nursing is "scheduled" and the mother and her young remain separate except during the nursing period. The mother nurses young about 3 to 5 times a day. Infrequent contact between the mother and her young may promote dispersal and is perhaps related to the solitary habit of Ganzu pikas. The length of time taken to nurse is positively related to littler size. These pikas have only two teats, therefore the mother must stay longer with the babies ensuring that all young receive milk.
Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female)
