From Ontario Nature:

What’s the difference between Caribou or Reindeer? Trick question—they’re actually the same species! Rangifer tarandus, also known as “Reindeer” in Russia and Scandinavia or when domesticated, and Caribou in North America, are the same leggy herbivores we know and love (especially if we’ve made the ‘Nice List’).

Despite their wide range, these majestic mammals are a threatened species. Their populations are dropping dramatically due to climate change and development which negatively affect their habitat and food security. Of the 51 Caribou herds living in Canada, not a single one is growing and at least 20 are declining.

Read more at https://naturecanada.ca/news/blog/meet-rudolph/