Flehmen and birth synchrony among female sable antelope,Hippotragus niger

Abstract

The role of female flehmen behaviour in maintaining reproductive synchrony was investigated in 11 adult female sable antelope and their associated offspring maintained on a 13·2-ha pasture at the National Zoological Park's Conservation and Research Center near Front Royal, Virginia. All occurrences of aggression and flehmen by adult females were recorded during 274h of observation over a 10-month period (1987), and the timing of births was recorded for four birth seasons (1986-1989). In each year, dominant females tended to give birth in temporal proximity to other females (birth clustering), while subordinates gave birth asynchronously. Flehmen frequency fluctuated seasonally, reaching highest levels just prior to the approximated time of conception. Adult, multiparous females were the primary targets of flehmen. There was positive assortment by reproductive state: pregnant females attended to urinations by other pregnant females and postpartum females responded to other postpartum females. Prepartum flehmen rates reliably predicted subsequent birth synchrony, and the degree of synchrony between a given pair of females was directly proportional to the frequency with which they sampled each other's urine in the preceding year. These results indicate that flehmen is a potential mechanism by which female sable antelope can manipulate the timing of both conception and parturition.