By the time peak oestrus approaches there may be four or five males gathered around the female, all anxious to mate. The smaller males give way to the bigger ones. Some Chinese workers at Wolong observed the pattern of the encounter. The following is their field notes in April 1983 describing a set-to between four males for the favours of a single female:

'A female sits in a fir about 10 m above ground. Wei (an adult male) bleats near the base of the tree. He climbs 3 m up the tree, but five minutes later descends and, in walking away, passes the observers at 2 m. Another male, large and uncollared and with blood on forehead and ear, approaches then chases Wei a short distance. Wei, however, returns and once more climbs the tree in which the female sits; he bleats, she moans. Two minutes later Wei descends. An uncollared male is now near the tree too, as is the male Pi. The latter two face each other, moan, roar, and tussle until the uncollared male withdraws. At 09:45, Pi ascends the fir and mounts the female, she crouched, bridging two branches, he balanced by her rump. Wei and the other male moan below. At 09:56, Pi mounts the female for a minute and then once more briefly; at 09:59, he places a forepaw on her back, sniffs her anal area and mounts as she chirps. Meanwhile yet another male has appeared, and the three squabble around the base of the tree.'

Pi and the female then climbed down and remained among the three males for a short while. Surprisingly perhaps, there was no fracas between Pi and the males but this was probably because being easily the biggest and most assertive, Pi had highest rank and had established his right to the female. Later that same day, however, Pi fought fiercely with a large male more his size. Through roaring, growling and swatting, they tried to bite each other with wide-open mouths and Pi eventually did bite his opponent's shoulder and chased him over a 6m high precipice. The next day there were still several pandas around the female, and although Pi was the dominant male, two of the subordinates succeeded in mating with the female. Multiple mating has several possible advantages for the female. It improves the chances that she will be fertilized, since there is always a small risk that the dominant male might be infertile.