Pappogeomys bulleri is thought to have a polygynous mating system. The range of one male overlaps with those of several females but ranges of the females do not overlap. Other than interacting while mating, individuals remain solitary.
Mating System: polygynous
The mating season for P. bulleri is year round, with the most active period being between late winter and early summer. Mating behavior and breeding activity begins at about nine months to one year of age for both sexes. Females are sexually mature once their pubic symphysis has opened, widening the birthing canal. After the first breeding season, the pubic symphysis is completely absorbed at the command of relaxin, an ovarian hormone. Males are sexually mature when the baculum and sex glands are fully developed.
Breeding interval: Pocket gophers breed one to two times in a breeding season.
Breeding season: The mating season is year round, but Pappogeomys bulleri most frequently mate in late winter, spring, and early summer.
Range number of offspring: 2 to 11.
Range gestation period: 18 to 20 days.
Range weaning age: 35 to 40 days.
Average time to independence: 2 months.
Range age at sexual or reproductive maturity (female): 6 to 12 months.
Range age at sexual or reproductive maturity (male): 9 to 12 months.
Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous
Female P. bulleri have six mammae: one pectoral pair and two lingual pairs. A female will have anywhere from 2 to 11 young in a litter. The gestation period is around 20 days. Newborn Buller's pocket gophers are altricial. On average, they weigh between 2.5 and 4 g, with cheek pouches not fully developed and eyes that are still under a thin layer of skin. In about one month, their cheek pouches, eyes and ears are opened and one week later they are able to use their cheek pouches to carry food. After two months, siblings begin to fight with one another, undergo weaning, and disperse soon afterwards. Juveniles molt to show adult pelage when they are near 100 days old.
Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)