Back in 1932, Australia was facing a problem with its national bird, the Emu. The trouble began when returning veterans from the Australian army switched to farming wheat. Their situation was already bad because of the great depression. It was further exacerbated by the falling prices of wheat and them not getting any subsidies from the Australian government.
This already bad situation was made worse when Emus in western Australia that migrated after their breeding season was over, found a good supply of food and water in the same region. This new source of food and water was the infrastructure set up for the farms. Having no reason to migrate, they started eating the crops and leaving large gaps in the fences which were then used by rabbits to further ruin the crops.
This video by the YouTube channel Oversimplified illustrates the measures that the government, and the farmers, took to get the situation under control. As is usual with videos made by this channel, it has been presented in its most simplified form and has been given the signature Oversimplified style of humour as well.
After the attempts made by the military to cull the birds proved to be ineffective, the Australian government refused any further requests for military intervention between 1934 and 1948. However, they kept the bounty system in place which proved to be more effective since, in 1934, over 57,000 bounties were claimed in a matter of 6 months.
At a later stage in the fight against the Emus, farmers started using exclusion barrier fencing, which turned out to be quite effective in not only keeping the emus out but also other pests like rabbits. They were also helped by the government releasing 500,000 rounds of .303 ammunition for them to use in an effort to control the damage to crops.