General:
* Prey: This is a general term for any animal hunted by another.
* Target: This emphasizes the hunters' focus on the fox.
* Game: This refers to wild animals hunted for food or sport.
Specific to the fox:
* Reynard: This is a traditional name for a fox, especially in stories.
* Vixen: If the fox is female.
* Kit: If the fox is a young one.
More dramatic:
* Victim: This highlights the fox's vulnerability.
* Fugitive: This emphasizes the fox's desperate flight.
The best choice depends on the specific situation and the tone you want to convey.