On average, an adult moose stands 1.8–2.1 m (6–7 ft) high at the shoulder. Males weigh 380–720 kg (850–1580 pounds) and females weigh 270–360 kg (600–800 pounds). The largest of all is the Alaskan subspecies (A. a. gigas), which can stand over 2.1 m (7 ft) at the shoulder, has a span across the antlers of 1.8 m (6 ft) and averages 634.5 kg (1,396 lbs) in males and 478 kg (1,052 lbs) in females. Typically, however, the antlers of a mature specimen are between 1.2 m (3.9 ft) and 1.5 m (4.9 ft). The largest confirmed size for this species was a bull shot at the Yukon River in September 1897 weighing 820 kg (1,800 lb) and was 233 cm (92 in) tall at the shoulder. The Moose of Alaska matches the extinct Irish Elk as the largest deer of all time. Behind only the bison, the Moose is the second largest land animal in both North America and Europe. The life span of an average moose is about 15–25 years.