Saki's short story is brilliant, at least, when it comes to one theme, the theme of what it means to be an interloper. While Ulrich and Georg see each other as interlopers and enemies, they are both interlopers in the natural world.
When the short story starts, we learn briefly of the history of the hatred between two men - Ulrich von Gradwitz and Georg Znaeym. Ulrich is a wealthy landowner who had a dispute with Georg. The courts ruled in favor of Ulrich, but Georg still used the land to hunt. In light of this, the two men hated each other.
In fact, Ulrich and his men are on watch to find Georg, presumably to kill him. As we can see, both men believe that the other is an interloper. The assumption here is that humans can own mother nature.
As the story unfolds, a storm knocks down a tree and the men are pinned underneath. Unexpectedly, the men reconcile. But it is too late, because wolves come onto the scene. The story ends. The implication is that both men will die. From this perspective, the men never considered one essential point, that they both were interlopers. To be honest, most readers probably never considered this point as well. The wolves, other animals, and nature were in the forest far before Georg and Ulrich. Men are interlopers in the natural world.