While warmer summers are helping increase the number of reindeer on a chain of islands north of Norway, scientists say warmer winters are causing the animals to starve.
Since the 1990s, researchers have been studying reindeer on Svalbard, 800 miles from the north pole. Two decades ago, the average weight of an adult reindeer was 121 pounds, and now, it's 106 pounds. Reindeer are herbivores, and in the summer, plants are more plentiful, giving the animals access to food. In the fall, it's easier for healthy female reindeer to conceive, and there are now more of the animals on Svalbard — researchers say the wild herd has grown from 800 in the 1990s to 1,400 now.
Arctic temperatures are rising faster than the world average, due to greenhouse gases building up in the atmosphere, and in the winter, there is less snow and more rain, which freezes into sheets of ice, making it more difficult for reindeer to get to their food. Scientists say some reindeer are starving to death, and females are giving birth to stunted young. When the reindeer are able to reach food, because there are now more of them, there's competition for plants. Prof. Steve Albon, ecologist at the James Hutton Institute in Scotland and leader of the study, told Reuters that while warmer summers are "great" for reindeer, warmer winters are "getting increasingly tough."