Female prairie voles (Microtus ochrogaster) fail to form a new pair after loss of mate.

We tested experimentally the hypothesis that failure to acquire a new mate by monogamously paired female Microtus ochrogaster that lose their mate represents pair-bonding behavior, not a lack of available males. Males were removed from reproductive male-female pairs and the females provided an opportunity to pair with unfamiliar sexually inexperienced or experienced males in a semi-natural arena. Only three of 22 (13.6%) females formed a new pair, two with inexperienced males and one with an experienced male. Three other females spent more time with an experienced male than with the inexperienced male, but did not form a pair or co-nest with that male. The results confirm field observations that availability of males is not a factor in the failure of female prairie voles to form a new pair following loss of their mate. This study concludes failure to form a new pair is associated with pair-bonding behavior.