During this time, male herds break up into smaller groups that search for females. The rut takes place in two phases. In the first phase, the male groups interact with the females that are all in oestrous. The higher the male's rank, the closer he can get to a female. Males perform courtship displays. In the second phase of the rut, one male separates from his group to follow an individual female. He displays to her and guards her from other males. Before copulation, the female moves her tail and courtship becomes more intense. They copulate and then he rejoins his group and reverts to the first phase. Gestation lasts around 167 days, and results in the birth of one or two kids, with twins making up about 20% of births. Alpine ibex reach sexual maturity at 18 months, but females do not reach their maximum body size for five to six years, and males not for 9–11 years. The horns grow throughout life, growing most rapidly during the second year of life, and thereafter by about a year, eventually slowing to half that rate once the animal reaches 10 years of age. Alpine ibex live for up to 19 years in the wild. Conservation status The Alpine ibex historically ranged through France, Italy, Switzerland, Liechtenstein, Bavaria, Austria and Slovenia. Starting in the early 16th century and with firearms becoming common, the overall population declined due to overexploitation and poaching. The ibex became extirpated in Switzerland and Germany by the 18th century, and was extirpated in Austria and northeastern Italy by the 19th century. They remained only in and around the adjacent Gran Paradiso and Vanoise Massifs, then both part of the Kingdom of Sardinia. Located in the western Italian Alps and the Maurienne valley in the north eastern French alps, bordering the Vanoise and Gran Paradiso Massif, the park was declared a royal hunting reserve in 1854 with the name of "Royal hunting reserve of Gran Paradiso" by Victor Emmanuel II, the first king of a united Italy. Ibex were protected from poaching and their numbers increased, reaching 3,020 in 1914. The ibex enjoyed further protection when Gran Paradiso was made into a national park in 1922. Animals from this population naturally dispersed into surrounding regions. However, reintroductions have been the predominant source of new populations. Today, the total population of Alpine ibex is over 30,000 and is considered