Sciurotamias davidianusPère David's rock squirrel

Geographic Range

Père David’s rock squirrels (Sciurotamias davidianus) are endemic to China and are usually found in the eastern and central parts of the country. According to the IUCN Red List it has an estimated extent of 2,755,263 km^2. They have a large range size, but it is unknown if this range has undergone any recent changes.

Habitat

Père David’s rock squirrels are terrestrial and are usually found in rocky habitats, which includes cliffs and canyon walls. They create burrows under rocks and use them for protection and seed storage. (Hongmao, et al., 2014)

Physical Description

Père David’s rock squirrels usually have brown, almost olive-grey pelage with pale undersides. Their pale eye-rings are considered to be distinctive to their species. They also have internal cheek pouches like chipmunks do. Their cheeks have dark patches of fur on them. The soles of their feet are also very hairy. This species displays sexual dimorphism in body size, with males being larger than females. Females have an average body length of 204 mm and average tail length of 142 mm. Males have an average body length of 212 mm and average tail length of 140 mm. Although this species displays sexual dimorphism, weights have not been classified by gender. Adults weigh an average of 260 g. Their dental formula is 1023/1013. (Zhao, et al., 2014)

  • Sexual Dimorphism
  • male larger
  • Average mass
    260 g
    9.16 oz
  • Range length
    346 to 360 mm
    13.62 to 14.17 in

Reproduction

Experts suggest that the sexual dimorphism displayed in Père David’s rock squirrels may indicate that they are polygynous, but further research required. (Callahan and Davis, 1982; Zhao, et al., 2014)

There is little information regarding reproduction in Père David’s rock squirrel or closely-related Chinese rock squirrels, but we know that Père David’s rock squirrels do not hibernate, which may change their mating patterns. North American rock squirrels that also do not hibernate may have two litters per year rather than one.

Members of the genus Sciurotamias have litter sizes of about 3 - the smallest litter size of any marmotine ground squirrel (tribe Marmotini). According to the IUCN Red List, Père David’s rock squirrels have a generation length of 3 years, which could mean they reach sexual maturity at around 3 years old, if parents are 3 when offspring are born. (Hayssen, 2008a; Hayssen, 2008b)

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual
  • Average number of offspring
    3
  • Average age at sexual or reproductive maturity (female)
    3 minutes
  • Average age at sexual or reproductive maturity (male)
    3 minutes

There is no information available regarding how much care Père David’s rock squirrels invest in their young. Rock squirrels in general give birth to altricial pups, so parental care is required after birth, but the extent is unknown for Père David’s rock squirrels. (Callahan and Davis, 1982; Zhao, et al., 2014)

Lifespan/Longevity

No lifespan information has been found regarding Père David’s rock squirrels and their closest relatives, Forrest’s rock squirrels (Sciurotamias forresti). The average lifespan for many rock squirrel species is 1 to 2 years, but we know the generational length for Père David’s rock squirrels is three years, so they must have longer lifespans - closer to that of the family Scuiridae. (Hayssen, 2008a)

Behavior

Père David’s rock squirrels are diurnal and do not hibernate, similar to rock squirrels in the southern United States. Père David’s rock squirrels have the ability to climb trees, but they rarely do. They spend large parts of their time hoarding seeds and are predominantly scatter hoarders, which means that they spread out the seeds they hoard into different areas. It has been shown that females hoard more than males, but males eat more seeds than females. This could be because females have to hoard seeds for their young, while males only have to feed themselves. However, it is difficult to say when there is no information on parental care for this species. (Luo, et al., 2014)

Home Range

There is no information on the home range of Père David’s rock squirrels.

Communication and Perception

No information is available on communication within Père David’s rock squirrels. Other species of rock squirrels make loud whistles when alarmed in order to alert other individuals of danger. (Callahan and Davis, 1982; Luo, et al., 2014)

Food Habits

Seeds are part of the primary diet of Père David’s rock squirrels. Studies have shown that they are seed hoarders. They hoard quickly around a food source to decrease competition, then slowly move the seeds closer to their burrows. They have also been noted to eat acorns as well as seeds. Pere David’s rock squirrels forage for food daily. (Hongmao, et al., 2014; Luo, et al., 2014)

  • Plant Foods
  • seeds, grains, and nuts

Predation

No information was found on predation of Père David’s rock squirrels. In general, squirrels are often preyed upon by larger mammals and birds of prey. Potential predators of Père David’s rock squirrels include dholes (Cuon alpinus), red foxes (Vulpes vulpes), corsac foxes (Vulpes corsac), and raccoon dogs (Nyctereutes procyonoides). (Smith and Xie, 2009)

Ecosystem Roles

An important role that most squirrels play in their ecosystems is that of seed dispersers. When hoarding and transporting seeds, they often drop some along the way. By spreading out seeds, squirrels reduce intraspecific competition amongst plants and improve the fitness of the plant species they consume. By eating seeds, Père David’s rock squirrels also likely help the dispersal of plants that depend on animals for their seeds to be distributed. They hoard seeds and nuts, like those of wild walnut trees. (Hongmao, et al., 2014; Smith and Xie, 2009)

  • Ecosystem Impact
  • disperses seeds
Mutualist Species
  • wild walnut

Economic Importance for Humans: Positive

There are no known positive economic impacts of Père David’s rock squirrels.

Economic Importance for Humans: Negative

According to the IUCN Red List Père David’s rock squirrels have large populations and can become agricultural pests. If population density in these agricultural areas becomes high enough, the loss of crops can result in an economic loss. (Zhao, et al., 2014)

  • Negative Impacts
  • crop pest

Conservation Status

Père David’s rock squirrels are considered to be of least concern, according to the IUCN Red List. They have what is presumed to be a large population, but actual population sizes and trends are unknown. Pere David’s rock squirrels face no known threats that can cause populations to decline severely.

Contributors

AHTZIRY SALAZAR (author), University of Washington, Laura Prugh (editor), University of Washington, Galen Burrell (editor).

Glossary

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

diurnal
  1. active during the day, 2. lasting for one day.
endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

granivore

an animal that mainly eats seeds

herbivore

An animal that eats mainly plants or parts of plants.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

polygynous

having more than one female as a mate at one time

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

stores or caches food

places a food item in a special place to be eaten later. Also called "hoarding"

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

References

Rock Squirrel. Accessed May 29, 2019 at https://www.animalspot.net/rock-squirrel.html.

"The IUCN Red List of Threatened Species" (On-line). Accessed May 27, 2019 at https://www.iucnredlist.org/species/19998/115154075.

Callahan, J., R. Davis. 1982. Reproductive Tract and Evolutionary Relationships of the Chinese Rock Squirrel, Sciurotamias davidianus. Journal of Mammalogy, 63/1: 42-47.

Hayssen, V. 2008. Patterns of body and tail length and body mass in Sciuridae. Journal of Mammalogy, 89/4: 852-873.

Hayssen, V. 2008. Reproduction within marmotine ground squirrels (Sciuridae, Xerinae, Marmotini): patterns among genera. Journal of Mammalogy, 89/3: 607-616.

Hongmao, Z., M. Steele, Z. Zhang, W. Wang, Y. Wang. 2014. Rapid sequestration and recaching by a scatter-hoarding rodent (Sciurotamias davidianus). Journal of Mammalogy, 95/3: 480-490.

Luo, Y., Z. Yang, M. Steele, Z. Zhang, J. Stratford, H. Zhang. 2014. Hoarding without reward: Rodent responses to repeated episodes of complete cache loss. Behavioural Processes, 106/2014: 36-43.

Smith, A., Y. Xie. 2009. A guide to the mammals of China. Journal of Mammalogy, 90/2: 520-521.

Zhao, D., Z. Chen, B. Li. 2014. Sex differences in anogenital distances and digit ratios in wild David’s rock squirrels Sciurotamias davidianus. Current Zoology, 60/2: 180-185.