Spermophilus suslicus

Geographic Range

The geographic range of speckled ground squirrels ( Spermophillus suslicus ) occurs in the Palearctic range, specifically eastern Europe. Their range extends east from a small portion in south-eastern Poland towards the Volga River in central Russia. The distribution of speckled ground squirrels occurs in most parts of Ukraine and Moldova. Small fragmented populations are present in east and western parts of Belarus.

• Biogeographic Regions
• palearctic palearctic
  • native native

Habitat

Speckled ground squirrels can occupy an array of habitats throughout the Palearctic range. Their typical habitat is the steppe areas or steppe meadows that occur throughout their north central distribution. They also tend to prefer cultivation sites, pasturelands, and open areas with low lying vegetation.

• Habitat Regions
• temperate temperate
• terrestrial terrestrial

• Terrestrial Biomes
• savanna or grassland savanna or grassland

• Other Habitat Features
• agricultural agricultural

Physical Description

Speckled ground squirrels are a small ground dwelling diurnal rodents, with an elongated body and short tail. They can reach lengths of 190 to 220 mm, and weigh from 180 to 220 g. The unique characteristic they can be identified by is the white tipped hairs that ultimately make up a speckled arrangement on the dorsal side of the body. They are predominately dark brown with a light cream color on their undersides, and they have short powerful legs. Speckled ground squirrels occur in the squirrel family , and have three subspecies: Spermophilus suslicus guttatus , S. s. boristhenicus , and S. s. suslicus . Speckled ground squirrels are easily identifiable and distinguished by their prominent white specks across its back. Juveniles or pups do not leave the den until maturity is reached, making it difficult to distinguish by color. European ground squirrels are closely related and may cause some identification issues due to similarities in appearance. European ground squirrels can be identified from their light brown coloration and white region from its jugular down the ventral side.

• Other Physical Features
• endothermic endothermic
• heterothermic heterothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

During the mating season just after females have emerged from hibernation, males use individuality in calls to attract females, and deter other males. They only breeds once a year right after hibernation. The males will mate with multiple females, and the females will raise the pups in a colony. Many of these colonies are experiencing population bottlenecks, raising the probability of inbreeding.

• Mating System
• polygynous polygynous

Speckled ground squirrels breed once yearly. Their breeding season occurs for two weeks as the females emerge from hibernation. Due to climatic conditions, they tend to have low intensity of breeding and low fertility rates. During late April and early May pups are born; these pups typically spend one month in the burrow until they disperse from the den. Information for gestation period and litter size is insufficient, however they can be compared to close relatives European ground squirrels . The gestation period of European ground squirrels lasts 27 days and the litter size on average is 6 pups.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• viviparous viviparous

Speckled ground squirrels give birth to a litter in early spring, with an average of 6 pups per litter. These pups are born underground, giving them protection from the elements and predators. Females tend to care for and protect the litters. Over the course of the weaning period, juveniles adapt to and learn alarm calls. It is noted that selective calling to juveniles and call rate is directly correlated to the emergence of young pups out of the den, suggesting there is some parental care. They spend much of their time viewing their surroundings and sounding alarm calls when predators are near, alarming the colony to take shelter.

• Parental Investment
• altricial altricial
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female
• pre-independence
  • provisioning
    • female
  • protecting
    • male
    • female

Lifespan/Longevity

Speckled ground squirrels on the high end can reach an age of six years. Juveniles are more vulnerable and less likely to make it through the first year. As juveniles, they contribute to 73% of the mortality rate, while adults only contribute to 58% of the mortality rates. There are no records of the speckled ground squirrels in captivity.

Behavior

Speckled ground squirrels are ground dwelling fossorial mammals. They spend a majority of their time on their hind legs scanning the surroundings in search of predators. Communication plays a vital role in survival for these squirrels; they tend to occupy sites of vast open grasslands making them vulnerable to visual predation. They not only use vocalizations for alarm calls, but also mating calls to fend off rival males and attract females. They dig burrows vertically and horizontally, the vertical burrows are temporary structures, whereas horizontal burrows are used for birthing and weaning pups.

• Key Behaviors
• terricolous
• fossorial fossorial
• diurnal diurnal
• motile motile
• sedentary sedentary
• hibernation hibernation
• colonial colonial

Home Range

Speckled ground squirrels live in large colonies, ranging from a couple individuals to 300 individuals per hectare. Most colonies are compact, having a home range of 2 to 28 hectares. They occupy vast areas that contain many burrows throughout. Many colonies can be located within 5 to 14 kilometers of each other.

Communication and Perception

Communication through vocalization plays a key role in the daily survival of speckled ground squirrels. They specialize in alarm calls that aid in alerting the colony of any potential predators. The speckled ground squirrel spends a vast majority of its time searching for predators, so they have developed visual acuity over time. Their alarm calls may be specialized to individuals in some cases. One good examples occurs when females develop individualized alarm calls when juvenile dispersal occurs.

• Communication Channels
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• ultrasound ultrasound
• chemical chemical

Food Habits

Speckled ground squirrels are most commonly be found eating sprouts. In some cases they eat grains, insects, and grasses. Some speckled grounds squirrel diets consist of bunch grasses ( Festuca rubra ) and motley grasses ( Fragaria viridis , Eryngium planum , Pimpinella saxigraga ).

• Primary Diet
• herbivore herbivore
  • granivore granivore

• Animal Foods
• insects

• Plant Foods
• roots and tubers
• seeds, grains, and nuts
• flowers

Predation

Speckled ground squirrels have evolved certain anti-predator adaptions over time. Their main anti-predator adaption is the acoustic communication between individuals in the colony allowing them to alert the colony of predators within close proximity. Speckled ground squirrels are fossorial, allowing for them to easily escape predation by going underground. They have very good eyesight, relentlessly observing the surroundings for potential predators.

• Anti-predator Adaptations
• cryptic cryptic

Ecosystem Roles

Speckled ground squirrels have some influence on soil aeration and altering habitat. They are fossorial; each individual in the colony digs multiple burrows throughout a landscape, which ultimately enhances soil aeration. Though they are only digging burrows they are also creating possible shelter for other species.

• Ecosystem Impact
• creates habitat
• soil aeration soil aeration

Economic Importance for Humans: Positive

Speckled ground squirrels have been studied on multiple levels from individuality in alarm calls to the dynamics of colonies of speckle ground squirrels. Studying these squirrels has allowed groups to learn more about conservation and population management.

• Positive Impacts
• research and education

Economic Importance for Humans: Negative

There are no known adverse effects of the speckled ground squirrel (Spermophilus suslicus) on humans.

Conservation Status

Currently speckled ground squirrels are near threatened, and completely protected in Poland under national law. They are also listed as endangered in the Polish Red Data Book and considered a Priority Species in the European Union Habitats Directive. There have been five newly constructed nature reserves in Poland to aid population conservation efforts. It has been proposed to use translocation for individuals from large colonies to boost genetic variation in other colonies at risk of deleterious genetic effects of bottlenecks. Agriculture has diminished much of their native habitat, and efforts to rebuild have been pursued.

Additional Links

Encyclopedia of Life

Contributors

Ryan Nutter (author), University of Wisconsin-Stevens Point, Christopher Yahnke (editor), University of Wisconsin-Stevens Point, Laura Podzikowski (editor), Special Projects.

References

Biedrzycka, A., J. Radwan. 2008. Population fragmentation and major histocompatability complex variation in spotted suslik, Spermophilus suslicus. Molecular Ecology , 17: 4801-4811.

Gondek, A., M. Verduijn, K. Wolff. 2006. Polymorphic microsatellite markers for endangered spotted suslik, Spermophilus suslicus. Molecular Ecology Notes , 6: 359-361.

Gondek, A. 2007. Saving the Suslik. Focus on Nature Conservation , 2/14: 18-21.

Matrosova, V., I. Volodin, E. Volodina, A. Babitsky. 2007. Pups crying bass: vocal adaptation for avoidance of age-dependent predation risk in ground squirrels?. Behavior Ecology and Sociobiology , 62/2: 181-191.

Matrosova, V., I. Volodin, E. Volodina. 2009. Short-Term and Long-Term Individuality in Speckeled Ground Squirrel Alarm Calls. Journal of Mammalogy , 90/1: 158-166.

Shilova, S., V. Neronov, O. Shekarova, L. Savinetskaya. 2010. Dynamics of Colonies of the Speckled Ground Squirrel (Spermophilus suslcus Guld., 1770) on the Northern Boundary of the Habitat. Biology Bulletin , 37/5: 532-536.

Volodin, I., E. Volodina, V. Matrosova, L. Savinetskaya, O. Shekarova, V. Voytsik. 2008. Population density does not affect the alarm call characteristics in speckled ground squirrel (Spermophilus suslicus). Lynx , 39/2: 333-342.

Yu, H. 1995. "Spermophilus citellus-European ground squirrel" (On-line). Animal Diversity Web. Accessed August 22, 2012 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Spermophilus_citellus.html .

Zagorodnyuk, I., Z. Glowacinski, A. Gondek. 2008. "Spermophilus suslicus (Speckled Ground Squirrel, SPECKLED GROUND SQUIRREL, Spotted Souslik)" (On-line). The IUCN Red List of Threatened Species. Accessed August 21, 2012 at http://www.iucnredlist.org/details/20492/0 .