I need to start by talking about St. Matthew’s Island. In the 1940s, reindeer were introduced to St. Matthew’s Island as an emergency food source for the people manning the observation station on the island. There was a lot of lichen on the island, the primary food source of reindeer. The humans didn’t stick around long after world war 2, but researchers did check on the reindeer population from time to time. Initially, they were thriving. Their population increased rapidly, and they were healthy. After some time, they had spread across the island in massive numbers. The lichen was getting thin on the ground. By the 1980s, there were no more reindeer on St. Matthew’s Island. They starved to death after eating everything that could sustain them.