The largest horde verifiably observed in this way contained over 1,300 individuals, in Lopé National Park, Gabon—the largest aggregation of nonhuman primates ever recorded.[36] In the wild, males disperse and only female mandrills remain in their birth group. This benefits females to establish strong relationships with their relatives which can provide support during conflicts, better offspring and longer lifespan.[37][38] These hordes are made of adult females and their dependent offspring.[39] Males live a solitary lifestyle, and enter hordes only when females are receptive to mating, which lasts three months each year.[25][39] All-male bachelor groups are not known to exist.[25][39] The mating season of the mandrill takes place from June to October, which is when the sexual swellings of the female occur.[39] They breed every two years.