Karl Kranz

Mother-young relationships in captive ungulates: variability and clustering

Abstract We recorded four measures of mother-young association and the percentage of time the young spent lying during the first week after birth for 59 mother-young pairs belonging to 22 species and seven families of ungulates. The measures of mother-young association were positively correlated with each other and negatively correlated with the percentage of time the young spent lying. Three cluster analyses, based on various combinations of measures, separated the bovids into two groups recognizable as ‘followers’ and ‘hiders’. When the data on all 22 species were considered, five consistent species groups occurred in the three cluster analyses. The traditional follower-hider dichotomy provides a rough characterization of mother-young relationships in many ungulates, but does not adequately describe the behavioural variation present. By using standardized quantitative measures, we were able to characterize this variation and to establish a framework for future study.

Monogamy in the dik-dik

Abstract Kirks dik-dik ( Madoqua kirki ) is one of several ungulates for which field studies have confirmed monogamous pair bonding. Kleiman has discussed two forms of monogamy, obligate and facultative, which differ in the strength and frequency of pair-bond behavior patterns. This paper examines the nature of the pair bond in Kirks dik-dik with respect to these behavioral criteria. Pair formation and the pair-bond relationship was observed in 4 pairs of captive-born dik-dik at the National Zoological Park in Washington, DC, U.S.A. Quantitative data on pair-bond strength as measured by interaction rates, behavioral synchrony, and proximity were collected. These dik-dik exhibited features typical of a facultatively monogamous species. The pair bond was quickly established. Pair members typically interacted infrequently and the male assumed most of the responsibility for territorial maintenance. Males scent-marked significantly more often than females. Pair members maintained close proximity and exhibited a moderate degree of behavioral synchrony. The results are discussed with reference to studies of two other monogamous antelopes, klipspringer ( Oreotragus oreotragus ) and blue duiker ( Cephalophus monticola ).