These big fir trees provided beauty as holiday decor and then were used for the enjoyment of a very happy bison and other large mammals at a Chicago zoo.

More than 900 Balsam fir trees used during Brookfield Zoo Chicago’s Holiday Magic event are repurposed every year as mulch, seasonal habitat enhancements and animal enrichment.

“Our animal care teams are always looking for creative ways to add enrichment for the animals around the Zoo,” the zoo said on Facebook . “These trees filled with treats are a great way to encourage foraging behaviors and add a fun twist to feeding time!”

The video above shows the resident American bison, Joe, effortlessly tossing his tree into the air. What appears as play is an effort by Joe to rub his face against the needles to help shed his coat, according to the zoo. Hudson the polar bear is seen toppling its tree as he uses his nose to find meat, watermelon, honeydew and apples. Tim, a grizzly bear, is very interested in the tree’s ice-block base. Lions Brutus and Titus walk around inspecting their trees before one jumps up to carefully remove a treat.

Enrichment activities like this have mental and physical benefits for the animals, meeting behavioral needs like foraging, exploration and more, the zoo said.