Introduced species are a leading driver of biodiversity loss worldwide, and in Aotearoa, the impact is especially stark. Our native birds, reptiles, and bats evolved without mammalian predators, making them especially vulnerable to rats, stoats, possums, and feral cats.

These threats have pushed many species to the brink, including our endemic bats: the long-tailed bat (Chalinolobus tuberculatus) and the lesser short-tailed bat (Mystacina tuberculata).

While toxins remain a key tool in New Zealand’s predator control strategy, their use is not always suitable, especially when the risk to non-target species is high. Our bats, for example, have ground-foraging behaviour that makes them highly susceptible to ground-laid toxins. Several bat fatalities have occurred in recent years during toxin operations.

That’s why a recent study published in the New Zealand Journal of Ecology (Bridgman et al., 2025) is such welcome news.

New study finds A24s safe around New Zealand’s bats

The study, led by researchers from the Department of Conservation and University of Otago, set out to fill a knowledge gap about bat behaviour around the Goodnature A24 trap to check its viability as a tool for predator control in these areas. The study found no evidence of bat interactions with Goodnature A24 traps in Pureora Forest Park, even in areas with high bat activity.

This is a significant finding and great news for bats that the A24 is a viable control method in these areas (noting the caveats and considerations below).

What was tested and found

Researchers deployed 40 disarmed A24 traps, baited with standard Chocolate Automatic Paste Pumps, and mounted at our recommended height of 120mm off the ground. These were monitored using:

• Trail cameras to detect physical interactions
  Acoustic bat monitors to detect echolocation activity

• Monitoring was conducted across two active periods (Nov/Dec and Mar/Apr), totalling over 2,400 trap nights.

During the first monitoring period (Nov–Dec), cameras found:

• 0 bat interactions

• 1,299 rat interactions

• 1,473 mouse interactions

• 1,068 possum interactions

• 3 stoat interactions

During the second period (Mar–Apr), cameras found:

• 6 bat fly-bys (no interactions with traps*)

• 2,601 rat interactions

• 6,640 mouse interactions

• 1,800 possum interactions

• 7 stoat interactions

In zero cases did a bat land on, approach, or interact with a trap.

* Still images taken from camera trap footage of lured, but disarmed, Goodnature A24 resetting traps in Pikiariki, Pureora Forest Park March 2021. Image a) is a bat flyby. Image b) appears to show a lesser short-tailed bat observing a mouse before flying away.

Side note – Resetting matters

The data also reinforced a key advantage of the A24: self-resetting performance.

Each trap saw an average of 10–12 interactions per night. If a single-set trap had fired on the first rat, all subsequent opportunities would have been missed until its next service. Resetting = more control, less labour.

Caveats and considerations

As with any study, it’s important to acknowledge the boundaries of the findings. The authors caution: “We caution against extrapolating the results of our study to different types of trap, lure, and trap positioning.” – Bridgman et al., 2025

This study used:

• A24 traps

• Chocolate A.P.P. lure

• 120mm mounting height (as recommended by Goodnature)

Alternative configurations could yield different outcomes and should be tested independently.

A win for our vulnerable bats

From the beginning, Goodnature has been committed to minimising harm to non-target species. The A24 was designed to be humane, efficient, and selective, and we’ve continually improved the product and its instructions for use based on lessons from the field.

We’re pleased to have this robust, independent data confirming that A24s can be confidently deployed in sensitive bat habitats, adding to their proven value in remote terrain, toxin-restricted areas, and conservation-critical zones.

We’d like to acknowledge the researchers: Lucy Bridgman, Jade Watkin, and Nic Gorman, and all those who contributed to this important work.

🔗 Read the full study in the New Zealand Journal of Ecology