A guide to estimating the age of Masai giraffes (Giraffa camelopardalis tippelskirchi)

This is a guide for estimating the age of Masai giraffes (Giraffa camelopardalis tippelskirchi) with noninvasive methods.  Giraffes are commonly categorized into three age classes: calf (0 – 1 year), subadult (1 – 5 years) and adult (> 5 years). This categorization, though somewhat arbitrary, has its origins in giraffe life history. After birth, calves […]

Relationships between male giraffes’ colour, age and sociability

In species in which males signal competitive ability through secondary sexual traits, males with different levels of trait expression may adopt different reproductive tactics to maximize their reproductive success. In fission-fusion social systems, the most dominant males often roam widely in search of females in oestrus, and thus exhibit different patterns of sociability from subordinate […]

The impact of age-class and social context on fecal glucocorticoid metabolite levels in free-ranging male giraffes

One of the primary sources of perceived stress is the social environment of an animal and the interactions with conspecifics. An essential component of the response to a stressor is the activation of the hypothalamic–pituitary–adrenocortical axis, which results amongst others in a temporal increase in circulating glucocorticoid (GC) levels. Giraffes occur in a highly flexible […]

Umbilical cord stump retention and age estimation of newborn giraffes (Giraffa camelopardalis)

The umbilical cord stump is a conspicuous characteristic used to identify recently born giraffes (Giraffa camelopardalis) (Foster & Dagg, 1972; Langman, 1977; Leuthold & Leuthold, 1978; Pratt & Anderson, 1979; Pellew, 1981; Dagg & Foster, 1982). However, there is surprising disagreement over the length of time that the umbilical stump remains attached, with reports varying […]

Age proximity influences herd composition in wild giraffe

In many mammalian species, animals form subunits within larger groups that are often associated with kinship and/or age proximity. Kinship mediates fission/fusion social dynamics of giraffe herds, but the role of age proximity has been unexamined. Here, we analyze 34 years of data from a population of Thornicroft’s giraffe, Giraffa camelopardalis thornicroftii, living in Zambia in […]