A team of scientists has tracked a flock of bar-headed geese as they made an incredible journey across the Himalayas.
Every year these incredible geese make a mammoth trip over the Himalayan mountains from central Asia to India, where they spend winter before returning home.
Bar-headed geese can reach altitudes of more than 7,000 metres, and fly while breathing in air that has less than 10% oxygen.
A team led by Bangor University in Wales put trackers on seven geese to try and unlock how they can endure such harsh conditions.
Watch Jenny's report to see what they discovered.