The "Emu War", while funny to imagine, was not exciting affair that folk lore and popular culture has made it out to be. The 'war' came about due to the destruction wrought by some 20,000 emus rampaging through wheat fields in Western Australia searching for water. The habit of the emu to run in straight lines also resulted in large stretches of fences to be knocked down. These were important as they were critical to keeping rabbits out of farming areas. In frustration, the farmers asked for military assistance in culling the birds and a force of three soldiers, a Major, a Sergeant and a gunner were sent, equipped with two Lewis Machine Guns. The guns jammed repeatedly and the speed of the birds made them difficult targets. The eventual withdrawal of the cull team came about due to an objection made by the Western Australian State Agricultural Department as they had not been consulted before the cull began. The Defence Department also did not want to set a precedent for the use of military personnel and equipment being used for animal control.

After the departure of the army team, a bounty was introduced for emu scalps and this resulted in a cull of some 57,000 emus in 1934.

Source: The West Australian Newspaper 1932 - 1934

In addition to a great response by u/TheWellSpokenMan, it should be also noted, that the results reported by the team were nowhere close to an indication of 'losing the war to the emus'. When the soldiers were eventually called off on 10th December, Mjr. Meredith, the commanding officer of the team reported that the five-week mission resulted in killing of 986 birds and possible deaths of 2500 more, as he noted that many emus were able to flee after being hit and both soldiers and local farmers were reporting finding the dead birds with gunshot wounds that have possibly collapsed only some time after being shot. So, if we take the final report at the face value, it would mean that the three-men team was able to eliminate roughly 3.500 emus or 17% of the estimated 20.000 birds roaming the area north of Walgoolan, using 3 bullets per bird (the team was equipped with 10.000 bullets). But even if we accept only the reported number of the birds hunted directly, it would sum up to the elimination of 5% of the all emus with the ammo expenditure of roughly 10 cartridges per killed bird. Given that weapons used were unorthodox to say the least and the gunners lacked any practical skills of engaging such targets, these results can be considered truly outstanding from solely practical standpoint.

Thus, the 'Emu War' was a definite success given the amount of resources dedicated (a single team of three men), but as it has already been said, military involvement in the animal control was cancelled due to political, legal and safety reasons, despite farmers asking the Defence Department for assistance few times in the following years. The problem has been eventually addressed by the aforementioned bounty system, usage of poisoned baits and the construction of 135 km Lake Moore Emu Fence that was finished in 1959, and the subsequent strengthening of the existing Rabbit-Proof Fences to prevent damage by wandering emus.

Johnson, M., Feathered foes: soldier settlers and Western Australia's 'Emu War' of 1932 in: Journal of Australian Studies, vol 30, issue 88, pp. 147-157.