1080 vs trapping — pest control methods in NZ compared

1080 is the most widely discussed pest control tool in New Zealand, but it is not the only one. Trapping, brodifacoum, and other methods each have distinct strengths and limitations. Understanding how they compare helps explain why 1080 remains the primary tool for large-scale operations — and where alternatives work better.

Aerial 1080

How it works: Cereal or carrot baits laced with sodium fluoroacetate are dropped from helicopters across large areas of bush. Targets possums, rats, and stoats.

• Scale: Can cover tens of thousands of hectares in a single operation — no other method matches this
• Cost: Roughly $15–25 per hectare for aerial application, making it the cheapest option at scale
• Effectiveness: Typically kills 90–95% of possums and 70–90% of rats in the treated area
• Limitations: Non-selective among mammals — kills any mammal that eats enough bait. Requires public notification and can restrict land access. Significant risk to dogs
• Persistence: 1080 is biodegradable and breaks down in the environment within weeks to months

Trapping

How it works: Kill traps or live-capture traps set on the ground along trap lines, checked regularly by volunteers or paid contractors.

• Scale: Effective for small to medium areas — community trap networks, urban bush reserves, predator-free fenced sanctuaries
• Cost: $50–150+ per hectare per year including labour, trap maintenance, and logistics. Cost per hectare rises steeply in remote or rugged terrain
• Effectiveness: High in accessible areas with consistent effort. Less effective in steep, remote bush where trap density and checking frequency drop
• Limitations: Labour-intensive. Cannot practically cover the scale required for mast-year responses across the DOC estate. Traps need ongoing maintenance and monitoring
• Advantages: Species-selective (traps can be designed for specific animals). No poison in the environment. Strong community involvement model

Brodifacoum (second-generation anticoagulant)

How it works: A slow-acting poison delivered through bait stations. Widely used for rodent control in urban areas, farms, and island eradications.

• Scale: Primarily used in bait stations for targeted areas. Also used for island eradications where complete pest removal is the goal
• Cost: Moderate — bait stations require infrastructure and ongoing replenishment
• Effectiveness: Very effective for rodents. Used successfully in island eradications (e.g., Rangitoto, Campbell Island)
• Limitations: Persists in the environment far longer than 1080 — it bioaccumulates in the food chain, meaning predators and scavengers can be poisoned by eating contaminated prey over time. This is a significant environmental concern
• Risk to pets: Dangerous to dogs and cats. Secondary poisoning risk is higher than 1080 because of bioaccumulation

Ground-based 1080 bait stations

How it works: 1080 bait delivered through secured ground stations rather than aerial drops. Used where aerial application is not appropriate — near towns, farms, or sensitive areas.

• Scale: Medium — suitable for buffer zones, farmland boundaries, and areas near habitation
• Cost: More expensive per hectare than aerial but cheaper than trapping
• Effectiveness: Good for possums. Less effective for rats and stoats compared to aerial coverage
• Advantages: More controlled application. Lower risk of bait drift. Can be used year-round

Why does New Zealand still rely on 1080?

The core reason is scale. New Zealand has roughly 8 million hectares of conservation land, much of it steep, remote, and roadless. No combination of trapping, bait stations, or alternative poisons can currently protect native species across this area at an affordable cost. 1080 is the only tool that can be deployed quickly across large tracts of bush when a mast year triggers a predator population explosion.

Trapping is increasingly important — particularly through community-led projects like Predator Free 2050 initiatives — and works well in accessible areas. But for the backcountry, 1080 remains the primary defence for species like kiwi, kākāpō, and mohua.

Regardless of which methods are used in your area, knowing when an operation is happening helps you make informed decisions about access, pet safety, and water precautions.