This was the best year for monarch butterflies since the early 2000s, with an estimated 225 million in the eastern population overwintering in Mexico. At times there were millions in the air at once.Most of the footage was at the El Rosario, Chincua and Cerro Pelon monarch sanctuaries.

To see a video of birds (Black-backed Orioles and Black-headed Grosbeaks) eating monarchs at the reserve, go to my video here:    • Birds Eating Monarch Butterflies