Bilbies have a polygynous mating system in which the most dominant male will mate with any females while lower males will mate with females equal or below them in the social hierarchy.
Bilbies have a polygynous mating system in which the most dominant male will mate with the most dominant female and additional females while lower males will mate with females equal or below them in the social hierarchy.
Male bilbies initiate sexual interactions by approaching and following a female. This is followed by the male sniffing the female around her face, shoulders, flanks, or under the tail as well as licking the female’s urogenital opening. Females may also sniff the male. Females may aggressively rebuff the advances of lower-ranked males. Copulation seems to take place underground with the longest mating sessions recorded taking place for around 18 hours.
There is no evidence of pair bonding, though males will often scent mark the burrow after mating with a female. This is thought to ward off lower-ranked males.
These results were observed in a study of captive bilbies. Little has been recorded about bilby mating in the wild due to their decreasing numbers and semi-fossorial, nocturnal lifestyle.