1080 drop seasons — when do they happen in NZ?

1080 operations in New Zealand do not follow a fixed calendar. Timing is driven primarily by pest population cycles, funding, and logistical factors — which means there is no single "1080 season" to watch out for. That said, there are patterns worth understanding.

The mast year cycle

The most significant driver of large-scale 1080 operations is the beech mast cycle. Every few years, beech forests across the South Island (and parts of the North Island) produce an unusually large seed crop — a mast year. This triggers explosive population growth in rats and stoats the following spring and summer, which in turn causes severe predation of native birds including kiwi, kākāpō, and whio.

DOC monitors beech seed fall each autumn and typically announces large-scale operations for the following year when a mast event is confirmed. This means operations following a mast year tend to be larger, more widespread, and better publicised than routine operations.

Typical timing within a year

Most aerial 1080 operations are conducted between late winter and early summer (July to December). This timing targets predator populations before they reach peak density, and conditions are generally better for aerial application — lower rainfall, less foliage density, and more stable flying weather.

Operations outside this window do occur, particularly ground-based bait station programmes which run year-round, and TB control operations which follow stock movement and contact risk rather than seasonal patterns.

Regional variation

• South Island high country and West Coast — the most active 1080 zones in mast years, covering large areas of DOC estate
• Northland and Coromandel — kiwi sanctuaries with regular ongoing operations independent of mast cycles
• Hawke's Bay, Whanganui, and other North Island hill country — a mix of DOC and regional council operations, often TB-focused

How to stay ahead of it

Because operations are announced weeks to months before they begin, setting up a 1080Alert for your area gives you advance warning rather than finding out from a sign at a trailhead.

If you live or regularly work in an area with beech forest, pay attention to coverage of beech seed fall each autumn — a reported mast event is a reliable signal that a significant operational season is likely the following year.