In a study on the population dynamics of the Uludag Frog, Rana macrocnemis Boulenger, 1885 at Uludag, 4,952 individuals were marked with toe-clipping, visible implant elastomer and vi alpha tags between 2006 and 2008. 47.1% of the population consisted of males, 39.0% of females and 13.8% of juveniles, and a male-biased sex ratio was observed. According to the formula of Jolly-Seber, the mean population size was calculated for individual study plots as 1,535 in Kirazliyayla, 1,578 in Sarialan, 1,481 in the Hotels District, 823 in Lake Kilimli, 742 in Lake Kara, 675 in Lake Aynali, 658 in Lake Kogukdere, and 151 in Lake Heybeli. The total population size was estimated at 7,643 individuals (3,113 in forest, 4,530 in the subalpine belt) in 1.30 ha areas (0.14 ha in forest, 1.16 ha in the subalpine belt) in study plots of Uludag ranging between 1,476 to 2,450 in a.s.l. The capture probability ranged from 0.21 to 0.93 and the survival rate ranged from 0.57 to 0.98 among the populations, and the mean population density was calculated as 0.19-2.52 individuals/m(2). The age in the population varied between 2 and 11 years, and the median age was calculated as 4 in males, 4.5 in females. The sexual maturity age ranged from 2nd to 6th years depending on altitude (from 1,476 to 2,450 m). It was found that the breeding period commenced in early April upon the melting of the snow and extended until the end of June, depending on altitude. The mean number of eggs in an egg mass was calculated to be 987+/-326. Spawned eggs hatched in 7 to 32 days depending on weather conditions and metamorphosis was completed in 46 to 130 days.