The smell of fear warns other voles. For a prey animal, the smell of a predator is one of many signals for danger. New research has shown that prey individuals can communicate with each other about the presence of a predator. An individual, who was attacked or chased by a predator, can signal danger with its body odor, i.e. Alarm pheromones. The studies showed that alarm pheromone caused different responses in vole behavior and reproduction compared to the direct predator odor. Source 3u.
I'm pretty sure animals communicate through pheromones in general, so of course they would communicate fear that way. I bet its more instinctual than choice, but then again, there is always a chance it is choice? I guess we need to research more!