Gray wolves in Yellowstone Park, USA

This 6 March 2019 video from the USA says about itself:

Tracking the Gray Wolf in Yellowstone | Explorer

The gray wolf is a top predator that was nearly wiped out from North America. But in 1995, a recovery program began in Yellowstone with surprising results.

‘Epic Yellowstone’ captures the thriving ecosystem of the world-famous park. A new documentary series highlights the interactions of predatory, prey and environment. By Jeremy Rehm, 7:00am, March 17, 2019.