The site of the Red Forest remains one of the most contaminated areas in the world. However, it has proved to be an astonishingly fertile habitat for many endangered species. The evacuation of the area surrounding the nuclear reactor has created a lush and unique wildlife refuge. In the 1996 BBC "Horizon" documentary "Inside Chernobyl's Sarcophagus", birds are seen flying in and out of large holes in the structure of the former nuclear reactor. The long-term impact of the fallout on the flora and fauna of the region is not fully known, as plants and animals have significantly different and varying radiologic tolerance. Some birds are reported with stunted tail feathers (which interferes with breeding). Storks, wolves, beavers, deer, and eagles have been reported in the area.