During a BBC interview about the film, Werner Herzog was shot with an air rifle. The interview continued indoors. At the end, Herzog was encouraged to check his wound. Despite having "a bruise the size of a snooker ball, with a hole in it," Herzog declared "It was not a significant bullet. I am not afraid."
The fatal bear attack on Treadwell and Huguenard occurred near Upper Kaflia Lake in Alaska's Katmai National Park. Ironically, after Treadwell spent most of his adult life trying to protect bears that were already protected by Alaska wildlife policies, his death forced authorities to kill two suspect, dangerous bears.
In the DVD extra about recording music for the documentary, Werner Herzog explained his vision for the material he asked the musicians to improvise. For instance, underneath the slow fight of two bears, the cello and the upright bass are menacing. When Treadwell swims near a bear, it's a dangerous foreshadowing, not the harmony it appears to be.