On the way to the falls, this is an animal hospital and center for rehabilitation of injured wildlife. It also carries out valuable research into the Iguazú forest environment and has a breeding program for endangered species. You get walked around the jungly 20-hectare park by one of the staff, who explains about the birds and animals and the sad stories of how they got there. The visit takes about 90 minutes.
Tours leave roughly every half hour. Guides who can speak English, will do so, but there are dedicated English tours at 9:30am and 2pm too.