At the Sedgwick County Zoo in Kansas brother and sister Amur (or Siberian) tigers are well on their way to adulthood as they come to their first birthday. At 1 year old they are only one quarter of the way to the typical mating age for these tigers – 4 years. However, they are already appearing large and in charge, growing rapidly from their days as cubs. A few photos included below show them as cubs a few months after being born, quite a change! At the zoo they are getting steady and nutritious meals on a regular schedule helping them grow strong and healthy, something that might be a little tougher out there in the wild. After 3 years the male should weight near 500 pounds while the female should be around 260. Some mature males have weighed more than 700 pounds. A litter size of 2 like this brother and sister pair is common but it is possible that as many as 6 are born together. In the wild they would be found in the harsh cold environments of China, Russia and Korea. They can travel long distances in their range and any animals in the area better watch out, even brown and black bears are occasionally preyed upon by these large tigers.