The farmland next to this cache was the site of the largest ever find of moa bones - in the 1890s. The area has been drained but in times of heavy rain there is evidence of the swamp that used to be there. More recently, in 1984 another dig was held. The moa here died of natural causes it is thought - they got stuck in the swamp and because they had no wings, were unable to pull themselves out. The swamp contained springs and that was how the bones were originally discovered. The local farmer wanted to harness the spring water for a water supply and he found bones. In the 1984 dig by the Waimate Historical Society, the Canterbury Museum carbon dated a bone at 2900 years old! If you wish you can visit the local Waimate Museum which has a permanent display about the moa.
More information: https://waimate.org.nz/blog/2018/8/8/moa
Congratulations to Isis58 on the FTF.