He may be used to soaring through the treetops, but no one was entirely sure how Marco the White-Tailed Black Cockatoo would react to a very different kind of tree.Hanging from some branches was a festive piece of what humans would call Christmas cheer, but this model Christmas tree, fashioned from cardboard and paper, topped with a bright star and with holes in the trunk, had a very important purpose. It had been created as part of the behavioural enrichment program for the animals at Taronga. Marco perched on top of the tree, greeting us with a cheerful ‘Hello!’ as he nibbled at some treats. Later on, food was placed inside the tree trunk’s holes for the other birds to try and retrieve.The tree was created by Behavioural Science Unit (BSU) volunteer, Alan Hind, who has worked on crafting enrichment for the animals at the zoo throughout the year. The seasonally themed tree, which will be left for the cockatoos and other parrots, is fashioned out of heavy-duty cardboard tubes and paper, held together with lots of papier-mâché instead of glue.Alan says a Christmas tree seemed like an “obvious” choice for Christmas, especially with lots of those cardboard tubes lying around (the enrichment team go through “thousands” of empty toilet paper rolls per year). It’s taken him about 10 hours all up to put together, and will be a challenging puzzle for the birds as they try to get at the food inside – most likely destroying the tree in the process. The BSU’s enrichment  creations provide the Zoo’s animals with extra mental challenges to keep their minds sharp, or can help them practice natural behaviours. In the case of Alan’s Christmas tree, the cardboard tubes are similar to real tree branches, which parrots would pull apart in an effort to find food.