4. The Emu War
There was an invasion of Australia by wild emus in October 1922, who invaded by munching on the plentiful wheat crops. What makes this fight to be one of the weirdest fights is the fact that the destruction of the crops by the Emus was so huge that the Emus were declared a threat to the stability of the whole region.
Australia attempted to fight this marauding Emus, but these attempts were are in futility. The Emus proved to be too fast and resilient. The end result of this war led to 20,000 deaths of people.