Advocacy Alert: Devastating by-kill confirmed in DOC’s Stewart Island 1080 operation

Devastating by-kill confirmed in DOC’s Stewart Island/Rakiura 1080 operation

New research has confirmed what the NZDA, hunters and conservation advocates have warned for years - aerial 1080 operations are causing severe, unacceptable by-kill of non-target game animals.

A Department of Conservation (DOC) predator control operation on Stewart Island/Rakiura has resulted in up to a 97% reduction in white-tailed deer activity in areas where standard 1080 bait was used, and a 75% reduction even where deer repellent was applied.

The operation was carried out across 43,100 hectares as part of ‘Predator Free Rakiura’ to protect the endangered pukunui (southern New Zealand dotterel).

While predator numbers were reduced, the by-kill on deer has been devastating.

NZDA has been advocating for the Stewart Island/Rakiura whitetail to be named a Herd of Special Interest (HOSI), and call for this to be action immediately. This status must be in place to protect this herd of significant value.

The NZDA 2025 Membership Survey found that members value the whitetail herds just as highly as wapiti and sika herds.

What the Research Shows

Monitoring by the Bioeconomy Science Institute during the August 2025 operation found:

• 97% reduction in deer activity where standard 1080 bait was used

• 75% reduction even where deer repellent was trialled

• Repellent did not prevent lethal exposure

Why researchers think Stewart Island/Rakiura deer are more vulnerable:

• Smaller body size

• Forest floor feeding behaviour

• Low natural food availability

• No prior exposure to 1080

DOC has suggested deer will “repopulate” the area within 3–4 years. This ignores the loss of mature animals, genetic stock, hunting opportunity, and cultural value.

What We Still Don’t Know

DOC has not released by-kill data for other non-target species. If deer losses were this severe, what is the true bi-kill impact on birds, invertebrates, and other wildlife? Without full transparency, the public is being asked to accept ecological harm without knowing the full cost.

Why This Matters

The Stewart Island/Rakiura white-tailed deer herd is:

• One of only two whitetail herds in the South Pacific

• A major contributor to the local economy

• A nationally treasured hunting and conservation resource

• Is identified and supported as the next Herd of Special Interest

Conservation must not come at the cost of indiscriminate ecological damage. Even DOC has now acknowledged the impact was “higher than anticipated” and has paused further aerial 1080 drops on Stewart Island/Rakiura for 2026.

NZDA’s Position

NZDA supports the Rakiura Whitetail Trust, Game Animal Council and local hunters, and will continue to advocate on behalf of all recreational hunters to protect this significant herd.

No further drops should happen and alternative methods (not using aerial poison) should be used to achieve predator free status.

We encourage members to share this update with interested friends and family, support and follow the Rakiura Whitetail Trust, and continue to support the NZDA as we advocate on issues like this.

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