The speckled ground squirrel or spotted souslik (''Spermophilus suslicus'') is a species of

rodent Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...

in the family

Sciuridae Squirrels are members of the family Sciuridae (), a family that includes small or medium-sized rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrel ...

from

Eastern Europe Eastern Europe is a subregion of the Europe, European continent. As a largely ambiguous term, it has a wide range of geopolitical, geographical, ethnic, cultural and socio-economic connotations. Its eastern boundary is marked by the Ural Mountain ...

. ''Spermophilus suslicus'' consists of three subspecies: ''S. s. boristhenicus'', ''S. s. guttatus'', and ''S. s. suslicus.'' It is threatened by

habitat loss Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

Taxonomy

Two populations separated geographically by the

Dnieper River The Dnieper or Dnepr ( ), also called Dnipro ( ), is one of the major transboundary rivers of Europe, rising in the Valdai Hills near Smolensk, Russia, before flowing through Belarus and Ukraine to the Black Sea. Approximately long, with ...

differ by diploid number, with those west of the Dnieper River, sometimes referred to as a

sister species In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

'' Spermophilus odessanus'', having 36 chromosomes and those east, constituting ''Spermophilus suslicus'' ''sensu stricto'', having 34. Recent

molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

data indicate that Palearctic ground squirrels are a complex, diverse group due to extensive genetic

introgression Introgression, also known as introgressive hybridization, in genetics is the transfer of genetic material from one species into the gene pool of another by the repeated backcrossing of an interspecific hybrid with one of its parent species. Introg ...

and incomplete lineage sorting since their recent

speciation Speciation is the evolutionary process by which populations evolve to become distinct species. The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within ...

during the

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

epoch and require multiple lines of evidence to distinguish their interpopulation relationships.

Description

The speckled ground squirrel has dark-brown fur with white spots on its back and a short, thin tail. It grows to a length of and a weight of . Its

dental formula Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, it is the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiology ...

is . It is smaller and less social than many other ground squirrels of the genus ''

Spermophilus ''Spermophilus'' is a genus of ground squirrels in the Sciuridae, squirrel family. As traditionally defined the genus was very species-rich, ranging through Europe, Asia and North America, but this arrangement was found to be paraphyletic to ...

''.

Distribution

It is found in

Belarus Belarus, officially the Republic of Belarus, is a landlocked country in Eastern Europe. It is bordered by Russia to the east and northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Belarus spans an a ...

Moldova Moldova, officially the Republic of Moldova, is a Landlocked country, landlocked country in Eastern Europe, with an area of and population of 2.42 million. Moldova is bordered by Romania to the west and Ukraine to the north, east, and south. ...

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It extends from the Baltic Sea in the north to the Sudetes and Carpathian Mountains in the south, bordered by Lithuania and Russia to the northeast, Belarus and Ukrai ...

European Russia European Russia is the western and most populated part of the Russia, Russian Federation. It is geographically situated in Europe, as opposed to the country's sparsely populated and vastly larger eastern part, Siberia, which is situated in Asia ...

, and

Ukraine Ukraine is a country in Eastern Europe. It is the List of European countries by area, second-largest country in Europe after Russia, which Russia–Ukraine border, borders it to the east and northeast. Ukraine also borders Belarus to the nor ...

. Its natural

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

is temperate

grassland A grassland is an area where the vegetation is dominance (ecology), dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes such as clover, and other Herbaceo ...

and it is also found on cultivated ground. It is threatened by the loss and fragmentation of its habitat. Causes of habitat loss include the expansion of agriculture and forestry, the reduction of pasturing, the development and growth of cities, and industrial development. Also, in some areas it is hunted as an agricultural pest. The speckled ground squirrel's range in Poland and southern Russia has contracted markedly, with only 10% of its area in the mid-twentieth century currently remaining. At the current rate of contraction of its range, the speckled ground squirrel will soon be extirpated from Poland.

Behavior

The speckled ground squirrel is a diurnal species which hibernates from October to April. It is active in the morning once the sun warms the area slightly, retreats to its underground den during the heat of the day, then reemerges late in the day for another feeding bout. It feeds mostly on grasses and cereals, although small vertebrates and arthropods are also eaten. Compared with other ''Spermophilus'' species, it lives in a relatively closed habitat with high grasses that block visibility during its active seasons. Individuals live in separate burrows within a larger colony. These colonies can be up to over 160 individuals per ha. It mates between April and May.

Gestation Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregn ...

ranges from 23 to 26 days. Four to eight cubs are born per litter. Sporadic hybridization occurs where ''S. suslicus'' occurs sympatrically with the little (''S. pygmaeus'') and European ground squirrels (''S. citellus'').

Predators

Though there have been no quantitative studies on all the predators of ''S. suslicus'', the

least weasel The least weasel (''Mustela nivalis''), little weasel, common weasel, or simply weasel is the smallest member of the genus ''Mustela,'' Family (biology), family Mustelidae and Order (biology), order Carnivora. It is native to Eurasia, North Ame ...

has been known to enter burrows and cause significant juvenile mortality, though it does not attack adults. However, conspecific predation may be more of a threat to the juvenile speckled ground squirrel than interspecific predators. Though

infanticide Infanticide (or infant homicide) is the intentional killing of infants or offspring. Infanticide was a widespread practice throughout human history that was mainly used to dispose of unwanted children, its main purpose being the prevention of re ...

in the wild has not yet been reported, the speckled ground squirrel has been infanticidal in captivity. The killer can be male, female, or both, and either eats the young or attacks and leaves it to die.

Alarm call

The speckled ground squirrel uses

alarm call "Alarm Call" is a song recorded by Icelandic singer Björk for her third studio album ''Homogenic'' (1997). It was released as the fourth single from the album, peaking at number 33 in the United Kingdom. The sped-up radio edit of the song was us ...

s for a variety of purposes. Primarily, the alarm call is used to warn conspecific squirrels of predators and to alert predators that they've been detected. Individual-specific alarm calls have been seen in ''Spermophilus suslicus'' which also contain age-related features but they lack the ability to distinguish between familiar and unfamiliar individuals nor can they distinguish sex.

Conservation

The population is believed to be experiencing continuing decline, with habitat fragmentation and loss occurring. In the 1996

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological ...

review, the speckled ground squirrel was listed as vulnerable, and in the 2008 and 2021 reviews, as

near threatened A near-threatened species is a species which has been Conservation status, categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature (IUCN) as that may be vulnerable to Endangered species, endangerment in the ne ...

. In the 2024 IUCN list update, it was listed as

critically endangered An IUCN Red List critically endangered (CR or sometimes CE) species is one that has been categorized by the International Union for Conservation of Nature as facing an extremely high risk of extinction in the wild. As of December 2023, of t ...

, due to a 99% decline in the global population over the past 30 years. According to the IUCN, habitat destruction due to

agricultural expansion Agricultural expansion describes the growth of agricultural land ( arable land, pastures, etc.) especially in the 20th and 21st centuries. The agricultural expansion is often explained as a direct consequence of the global increase in food and e ...

, as well as

climate change Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in ...

, puts the entire species at risk of extinction in the next 20–30 years. A

relict A relict is a surviving remnant of a natural phenomenon. Biology A relict (or relic) is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas. Geology and geomorphology In geology, a r ...

enclave population in Poland is protected under national law. The species is protected under Appendix II of the Bern Convention.

References

External links

{{Taxonbar, from=Q854681 Spermophilus Rodents of Europe Mammals described in 1770 Taxa named by Johann Anton Güldenstädt Taxonomy articles created by Polbot Habitats Directive species