THE DYNAMICS OF THE HORN GROWTH IN BULGARIAN CHAMOIS RUPICAPRA-RUPICAPRA-BALCANICA

Measures of horn growth of Bulgarian chamois Rupicapra rupicapra balca nica Bolkay, 1925 were compared between males and females. The hypothe sis that rapid early growth of horn is followed by slower subsequent g rowth was tested through the regression of the horn increment in the f irst two years against the third, fourth and fifth year respectively i n the same individual. Sexual dimorphism in annual growth increment wa s significant up to the third year, males having higher values than fe males. Negative correlation coefficients were found when regressing th e third, fourth and fifth individual annual increment on the second on e in males, thus showing that individuals which had horns which grew f astest in the first two years tended to have slower horn growth in sub sequent years.