Caucasian squirrels are native to Greece, Turkey, Armenia, Georgia, Azerbaijan, Iran, Iraq, Palestine, Jordan, Lebanon and Syria. The southernmost recorded range of their distribution is the forest covered mountains of Jarash and Ajlum in Jordan (Amr et al. 2006).
Biogeographic Regions: palearctic (Native )
Caucasian squirrels have a dental formula of incisors 1/1, canines 0/0, premolars 1/1, and molars 3/3, totaling 20. They have four fingered fore feet and five fingered hind feet. Sex differences in body length or mass are not evident (Amr et al., 2006; Hayssen, 2008).
Their ventral fur usually has a reddish color and fur color changes in winter. Adult dorsal fur color in winter ranges from pale-blackish-grey to pale-reddish-buff. The dorsal fur color in summer varies from very light-reddish-grey to pale-blackish-grey. The ventral fur color in winter ranges from light-yellowish-buff to light-reddish-buff. The ventral color in summer varies from reddish-yellow to rich orange. Some individuals have ear tufts in winter, but these disappear in summer through autumn. (Albayrak and Arslan, 2006; Amr et al., 2006; Hayssen, 2008; Pamukoglu and Albayrak, 1996; Wauters and Dhondt, 1992)
Average mass: 335.3 g.
Average length: 200.0 mm.
Other Physical Features: endothermic ; heterothermic ; bilateral symmetry
Sexual Dimorphism: sexes alike
Caucasian squirrels inhabit coniferous and temperate mixed forests. Their nest are usually found in the tree hollows, and they seem to prefer pine trees (such as oak, walnut, and willow) to deciduous trees. Their nests are also found under rocks, inside heaps of stones, and in residential areas, such as graveyards and abandoned cattle sheds (Amr et al. 2006).
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: forest
Other Habitat Features: suburban ; agricultural
Habitat and Ecology
Caucasian squirrels are herbivorous. They mostly eat pine acorns, other seeds and fruits. They sometimes forage in residential areas, and some are observed scavenging food from garbage dumpsters. Their close relative Eurasian red squirrels, have similar diets to Caucasian squirrels, but it also eats berries and fungi. When food abundance is low, the diet of Eurasian red squirrels become varied, including birds’ eggs, tree bark, flowers, and invertebrates (Amr et al., 2006; Sadeghinezhad et al., 2012).
Plant Foods: seeds, grains, and nuts; fruit
Primary Diet: herbivore (Frugivore , Granivore )
There little information regarding ecosystem roles of Caucasian squirrels. However, they eat seeds and fruits and therefore, likely have an important influence on the forest ecosystem as seed dispersers. Additionally, food remains are found in several ground burrows further supporting this hypothesis (Miyaki, 1987).
Ecosystem Impact: disperses seeds
Little is known of predators of Caucasian squirrls. One study reports predation by large birds such as golden eagles or eagle owls. Many tree squirrels are eaten by many predators; Eurasian red squirrel are consumed by pine martens, wild cats, some owls, and raptors (De Cupere et al., 2009; Lurz, Gurnell, and Magris, 2005).
- golden eagles (Aquila chrysaetos)
- eagle owls (Bubo bubo)
Life History and Behavior
No detailed information is available regarding communication of Caucasian squirrels. They do call, so they may communicate with sounds (e.g. warning calls) like other tree squirrels. During breeding seasons, the closely related species, Eurasian red squirrels, communicate with body posture and sounds including chucking calls and teeth chattering. Eurasian red squirrel females in estrus also give off a scent that males can detect during mating season (Amr et al., 2006; Lurz, Gurnell, and Magris, 2005).
Communication Channels: acoustic ; chemical
Perception Channels: visual ; tactile ; acoustic ; chemical
There is no information available regarding average lifespan of Caucasian squirrels. Eurasian red squirrels live up to seven years in the wild and ten years in captivity. Since Caucasian squirrels inhabit some arid areas, water scarcity during the summer season can lower survival rates (Amr et al., 2006; Frentinos, 1972; Lurz, Gurnell, and Magris, 2005).
The mating system of Caucasian squirrels is currently unknown. However, a closely related species, Eurasian red squirrels, are well-studied. Eurasian red squirrel females in estrus give off a scent that males can detect during mating season. Males follow her for one or more hours, but males give up pursuit when she leaves their home range. Male’s home range size depends on their rank in dominance hierarchy, with dominant males holding larger ranges resulting in more chances to mate (Lurz, Gurnell, and Magris, 2005).
Mating System: polygynous ; polygynandrous (promiscuous)
There is no information available regarding general reproductive behavior of Caucasian squirrels, but their close relative, Eurasian red squirrels are well studied. Both males and females are sexually mature at 9 to 19 months old. Breeding season of Eurasian red squirrels is prolonged from December to January and August to September. Females are polyestrus and in season for only one day per breeding cycle. Mating peaks occur in winter and spring. The average gestation period in temperate tree squirrels ranges from 39 to 44 days, so it is assumed that gestation periods for Caucasian squirrels may fall within that range. Their close relative Eurasian red squirrels usually have two to five offspring per litter. Offspring have been weaned at eight to ten weeks (Lurz et al., 2005; Emmons, 1979; Mari et al., 2008).
Breeding interval: Caucasian squirrels breed twice yearly from December to January and August to September.
Breeding season: Caucasian squirrels mate in the winter and spring.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual
No information on the parental investment of Caucasian squireels was found. However, Eurasian red squirrels males do not provide parental care. Females nurse and protect offspring in their nests. Maternal care may extend after the young are weaned (Lurz, Gurnell, and Magris, 2005).
Parental Investment: altricial ; female parental care ; pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Provisioning: Female, Protecting: Female)
Caucasian squirrels are considered to be in the least concern conservation status. However, population decline is reported in some areas of their distribution, such as in Turkey mainly due to fragmentation and loss of habitat. Illegal hunting also harms Caucasian squirrl populations (Amr et al., 2006; Yigit et al., 2012).
IUCN Red List Assessment
Red List Category
Red List Criteria
The species was considered abundant in Syria in the woods south of mount Hermon in 1866 (Harrison and Bates 1991). In Iraq in 1959, Hatt found the species near Sarsank, where up to twelve individuals occupied a single hollow tree (Harrison and Bates 1991).
Population density has not been quantified, but fluctuations apparently occur.
Relevance to Humans and Ecosystems
Little is known about the negative economic effects of Caucasian squirrels on humans. However, one study reports that they forage at residential gardens so they may have negative impacts on gardens (Albayrak and Arslan, 2006).
Not much information of positive economic importance for humans is found, but some studies mention that people keep Caucasian squirrels, as a companion pet (Khazraiinia et al., 2008; Tootian et al., 2012; Masseti, 2010).
Positive Impacts: pet trade
The Caucasian squirrel (or Persian squirrel) (Sciurus anomalus) is a tree squirrel in the genus Sciurus found in Armenia, Azerbaijan, Georgia, Greece (only on the island of Lesbos), Iran, Iraq, Israel, Jordan, Lebanon, Syria, and Turkey. Its natural habitat is temperate broadleaf and mixed forests.
The species was identified by Johann Friedrich Gmelin in 1778 and named Sciurus anomalus, although it has also been credited to Johann Anton Güldenstädt. The common English name for the species is the Caucasian squirrel, also known as Persian squirrel.
Samuel Griswold Goodrich described the Caucasian squirrel in 1885 as "Its color is grayish-brown above, and yellowish-brown below". The Caucasian squirrel has a body length of between 20–30 centimetres (7.9–11.8 in) and can weigh between 200–1,000 grams (0.44–2.20 lb).
The species mainly lives in forested areas featuring coniferous and/or deciduous trees in Turkey and throughout the countries in the Middle East and Eurasian regions but the range also stretches as far south east as Iran and Iraq. In the Mediterranean, they are native to Gökçeada and Lesbos. It is one of two species of the genus Sciurus to be found on Mediterranean islands. The Caucasian squirrel lives in areas as high as 2,000 metres (6,600 ft). They live in trees, where they make their dens. Their diet includes nuts, seeds, tree shoots and buds.
A survey in 2008 found that the species remained abundant within Turkey, however declines are noted in population within the Levant region. The guides for a survey in 1993 in Israel stated that they considered the species to be nearly extinct within the area studied. Whilst the Caucasian squirrel is threatened by poaching and deforestation, the declines recorded are not sufficient to qualify them as anything other than "Least Concern" by the International Union for Conservation of Nature. Hunting of the species is banned by the Central Hunting Commission, and the Caucasian squirrel is protected by the Bern Convention and the EU Habitats Directive.
- Yigit, N., Kryštufek, B., Sozen, M., Bukhnikashvili, A. & Shenbrot, G. (2008). Sciurus anomalus. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 6 January 2009.
- Thorington, R.W., Jr.; Hoffmann, R.S. (2005). "Family Sciuridae". In Wilson, D.E.; Reeder, D.M. Mammal Species of the World: a taxonomic and geographic reference (3rd ed.). The Johns Hopkins University Press. pp. 754–818. ISBN 0-8018-8221-4. OCLC 26158608.
- Masseti, Marco (2012). Atlas of Terrestrial Mammals of the Ionian and Aegean Islands. Boston: De Gruyter. pp. 60–61. ISBN 978-3110254570.
- Goodrich, Samuel Griswald (1885). Johnson's Natural History 1. New York: A.J. Johnson & Co. p. 372.
- "Appendix B1 - Mammal Species Dossier" (PDF). British Petrolleum. October 2002. Retrieved 14 July 2013.