The Baddies - Threats to NZ Native Birds
Beech Forest Mast
Every four to six years, sometimes less, beech trees produce far larger than usual numbers of beech seeds, known as beech mast. This causes an explosion in populations of mice and insects due to the abundance of food. The increase in mice and insects means a greater food source for stoats, which then have an extremely productive breeding season. When the beech mast year is over, the mouse population crashes. The boosted stoat population then looks to additional sources of food especially birds, both adults and their clutches. The birds most at threat during stoat plague years are hole-nesting birds such as mohua/yellowheads, orange-fronted parakeets/ kākāriki and kaka.