REPRODUCTIVE STRATEGY IN A MONTANE POPULATION OF THE LIZARD LACERTA-SCHREIBERI (SAURTA, LACERTIDAE)

The mountain population of Lacerta schreiberi studied at the Sistema C entral (Spain) showed a narrow and highly synchronized reproductive pe riod, adjusted to short periods of annual activity, that are character istic of these Iberian areas. Adult females reached sexual maturity at a minimum age of four years. Only one clutch of eggs is laid per year . The average clutch size of 14 eggs was positively correlated with fe male body size. Clutch weight was high (25 to 56% of net female weight ), and incubation time was long (65 to 110 days). During incubation eg gs reached three times their initial weight. We found a noticeable var iability in some reproductive characteristics during the three years u nder study and among individual females. The greatest phenotypic plast icity was in the size of the eggs, incubation time, and the size of ha tchlings, while clutch size showed a higher stability in its average v alues.