SUBSCRIBE We use your sign-up to provide content in ways you've consented to and to improve our understanding of you. This may include adverts from us and 3rd parties based on our understanding. You can unsubscribe at any time. elk in their thousands leave the supervolcano each year to find higher grounds around the Yellowstone National Park. The annual mass migration gives the wild Yellowstone residents a chance to feast on fresh grass and calve for the Spring. However, scientists have discovered these centuries-old migration patterns are changing in response to environmental cues....…SUBSCRIBE We use your sign-up to provide content in ways you've consented to and to improve our understanding of you. This may include adverts from us and 3rd parties based on our understanding. You can unsubscribe at any time. elk in their thousands leave the supervolcano each year to find higher grounds around the Yellowstone National Park. The annual mass migration gives the wild Yellowstone residents a chance to feast on fresh grass and calve for the Spring. However, scientists have discovered these centuries-old migration patterns are changing in response to environmental cues....WW…