Snow on Mt Arthur

This photo was taken from the track going from the Flora carpark to the Mt Arthur hut. The forest on the slopes of Mt Arthur is classic New Zealand beech forest. Southern beech species (family Nothofagaceae) do well in cool, low fertility environments like Mt Arthur. Beech trees don’t flower every year, but occasionally there’s a summer when a whole lot of beech trees will flower. So much seed (called mast) is produced that introduced mammals such as rats and mice are able to have a bumper year offspring-wise, and then the large numbers of rats and mice keep the stoat population far too healthy over winter. When spring arrives and there isn’t enough beech seed to feed the rats and mice, they turn to the birds and their nests. Soon after, the stoat population explodes, and they decimate the native bird population. Masting is predictable – it’s triggered by a summer that’s warmer than the last one – so predator control can be intensified for mast years.