Body mass and lower jaw development of the female red deer as indices of habitat quality in the Ardennes

In order to investigate the most appropriate sampling to assess habitat effects on red deer, we analysed body mass, diastema length and length of the posterior part of the lower jaw of red deer females Cervus elaphus (Linnaeus 1758) in five study areas of the Ardennes (Belgium). Canonical discriminant analysis indicated that the female deer from the 5 study areas could be distinguished from each other on the basis of their body mass, diastema length and posterior length of the lower jaw. Body mass was the most correlated with the first canonical variable, while diastema length and posterior length of the lower jaw were less although significantly correlated. Age- -specific comparisons of means indicated that variations in body mass, diastema length and posterior length of the lower jaw of yearlings and > 4-year-old females were the most effective to separate the different populations and hence were good indices of respectively short and long term variations in environmental conditions. Univariate comparison of means suggested that posterior length of the lower jaw of yearlings could be a valuable alternative to body weight as an indice of habitat quality. The Von Bertalanffy growth equation with to fixed was used to assess the effect of habitat on asymptotic body mass and asymptotic jaw length and on the growth coefficients. The asymptotic values for body mass and jaw length were significantly higher where the habitat conditions appeared to be most favourable. In the poorest habitat, the growth of body mass and jaw length appeared slower, suggesting that female red deer, in this poorer habitat, could partially compensate their lower development as calves and yearlings by a longer growth period; however, only the growth coefficient of the posterior length of the lower jaw differed significantly from that of the best habitat.