Seasonal activity and terms of the emergence of hatchlings in True lizards (Sauria: Lacertidae) of Karadag Nature Reserve in Crimea and their relationship with climatic parameters

In the course of multi-year field research (2002–2022, and partially 2023) in the Karadag Nature Reserve (southeastern Crimea; 44.9º N, 35.2º E) the seasonal activity frame and terms of the emergence of juveniles were studied in two common species of lacertids: the Balkan wall lizard (Podarcis tauricus) and the Crimean rock lizard (Darevskia lindholmi). Activity during the winter period is characteristic for both species: over 22 years of observations, P. tauricus and D. lindholmi were observed in the winter months during 20 and 16 seasons, respectively. In P. tauricus the average for all years dates of the first and last observations of active individuals are February 13 and December 4; those in D. lindholmi are February 18 and November 26. The length of the activity period, determined by the dates of the first and last records, in P. tauricus is 65–91% of the total duration of the year, and in D. lindholmi is 62–89% of the year. The duration of the period of full activity (from the beginning of the species’ regular activity to the hibernation) is 236–321 days (273 days on average) in P. tauricus, and 227–302 days (260 days on average) in D. lindholmi. Egg-laying in P. tauricus occurs mainly in May–July (two clutches per season), while in D. lindholmi it occurs in July, but may continue into August (usually the only clutch per year). Therefore, the average for all years dates of the first registration of hatchlings differ by approximately seven weeks: July 12 in P. tauricus, August 29 in D. lindholmi. The timing of the emergence of yearlings of both species is positively correlated at a statistically significant level. In both species, a statistically significant correlation with the climatic characteristics of the area of study was found for a number of phenological phenomena. In many cases, the relationship between the phases of the lizards' life cycle and climatic parameters at the trend level was confirmed.