Since that looks like a dog collar on his head, I bet they lead him, or tie him u[ that way. One of our highlands is trained to lead that way.....
Great pics by the way! Looks like you got to see a lot of neat animals. As a funny side not, Hubby and I went to a zoo in Quebec while on vacation. We saw a herd of rhino's, and I took a pic. When we got home and were looking at the photo's, one of the males had a large DART sticking out of his butt. WHAT???!!! and we were home by then so we coldnt ask.