Père David's deer, also called milu, have begun fighting for supremacy as the annual mating season gets underway in Dafeng National Reserve, East China's Jiangsu Province. The breeding season usually starts in late May or early June, when stags are attracted by the hormones of their female counterparts.
Affected by weather conditions, the mating season this year has started later than usual, and could lead to the clashes between stags becoming more fierce because of the greater number of animals in the reserve. There are now 4,101 deer in the reserve, separated into herds of roughly 50 to 60 animals.
In each herd, only one milu stag, or the king, has the mating monopoly, as it is sexually and physically mature, normally weighing around 250 kilograms and sporting a pair of antlers two meters in length. However, it will lose 30 kilograms in weight after the three-month season ends in September.
The 4,101 milu in the reserve make up over 60 percent of the total global population. The species is considered as "extinct in the wild" by the International Union for Conservation of Nature (IUCN), but conservation efforts and a growing captive population could see the deer being one day reintroduced into the wild.