According to Canadian researchers, populations of caribou and reindeer have declined dramatically over the past three decades throughout the world. However, while the problem is global, the population declines are most extreme in the north, from Alaska to Scandinavia to Siberia.

Researchers studied 58 caribou and reindeer herds throughout the world, finding existing data on 42 of these herds. Of these 42 herds, 34 were found to be declining in population, with only 8 herds increasing in size. The available data showed that the population of all herds was down 57% from their maximum populations over the last 20 years.

Human activities such as logging and oil and gas extraction have had the most significant impacts on non-migratory woodland caribou. Without protection from these activities, caribou herds may disappear within the next 20-40 years.