The Bavarian Forest is a low-mountain area, densly forested and its core area is a national park. Part of the NP are two enclosures with wildlife like lynx, wolf, otters and bears, which once populated this area.
The enclosures are a well known hotspot for photographers and you will probably hardly find any place in Germany with more camera equipment crammed in such a small place. The exception to the rule are the matches of the German Bundesliga. I prefer winter to go to the NP, as there are less visitors and the enclosures look wilder and unspoilt, especially after heavy snowfall.
TAking pictures of the wildlife is not garanteed, it is not a zoo. The enclousures are huge and if the animals are hiding somewhere, you can wait for hours until something is showing up. Patience is key. But if you want to watch a lynx in the wild, you have to be out for years. In the enclosures you may wait for hours or maybe a day, but you will spot it eventually!