The tarsal glands of white-tailed deer (Odocoileus virginianus) are importa
nt in the dissemination of socially significant odours. The structure of th
e tarsal tufts, associated glandular secretions, and frequent urine deposit
ion provide a favorable environment for bacterial growth. We characterized
the bacterial flora associated with the tarsal tufts and compared it to the
flora from a region with lower glandular activity and no urine contaminati
on (mid-back). We identified 24 species of bacteria, 11 of which were speci
fic to the tarsal region. The average number of species on the tarsal gland
was higher in males than females (P = 0.04) and higher on the tarsal gland
than the back (P = 0.10) for both sexes. Species composition also varied a
mong sex and age classes. The bacterial composition and species richness of
the tarsal tufts suggests that this area is a suitable environment for mic
robes responsible for odour production. In particular, we found Corynebacte
rium xerosis, a microbe known to convert steroids to more odourous metaboli
tes in humans, on the tarsal glands and backs of both sexes of deer. Our re
sults are consistent with the hypothesis that microbes associated with the
tarsal tuft are important in odour production and that these microbes may t
ransform reproductive steroids excreted in the urine into odours that refle
ct an animal's social status or reproductive condition.