Ecology and some morphological characteristics of the Zootoca vivipara (Reptilia: Lacertidae) on the southern periphery of its range in the steppe zone (Orenburg State Nature Reserve, Russia)

Abstract

Occurrence of common lizards (Zootoca vivipara) in the steppe zone on the southern border of its range (site «Burtinskaya Steppe» of the Orenburg State Nature Reserve, Russia) is confined to habitat with azonal, predominantly meadow, vegetation on the hydromorphic soils. Habitat and microclimatic conditions supporting the existence of this hygrophilous forest species in the study area are caused by the spring and a rivulet flowing from it. The habitat transformation is caused by fires, construction of tourist routes, and beaver activity. All lizard individuals within study area were captured on two plots with a total area of 0.004 km2. The estimated population density has reached 7.8 individuals/1000 m2. We have found no differences in size of individual's body between studied Zootoca vivipara population and its populations from Penza region and Samara region which are also located at the edge of species range. Among females of this species studied in various parts of species' range, females of the site «Burtinskaya Steppe» differ based on their higher fertility and smaller mass of newborns than in more northern populations. We noted earlier appearance of lizard offspring than in most regions of the Eastern European and Asian parts of the range. We demonstrated similarity of some parameters of reproductive biology (length of female's body, timing of the offspring appearance, fertility, length and mass of newborn lizard) of the studied population with populations located in the Middle Volga Region.

Keywords

• abundance
• common lizard
• morphology
• habitat characteristics
• Orenburg region
• reproductive biology
• site «Burtinskaya Steppe»