From National Geographic
Average life span in the wild:6 to 8 years
Size:Head and body, 36 to 63 in (91 to 160 cm); Tail, 13 to 20 in (33 to 51 cm)
Weight:40 to 175 lbs (18 to 79 kg)
The diet of newly introduced wolves in areas that are high elk populations probably allows them to reach their genetic size limitations.