Low predator interaction on tree mounted trap

One of our customers has had our thermal camera in front of a tree based possum and rat trap for three weeks in the hope of seeing how well it performed. In this case the trap was the AT220 from NZ auto traps. 

Our customer set up the trap according to the manufacturer's instructions and had already caught one possum before the camera was put in front of it. Over the next three weeks the video shows 79 predators wandering past and zero catches. See below for a video of some of these interactions.

We find this is a very typical sort of result for any tree-based device when an area has been trapped for a while. This behaviour is not particular to the AT220 but to any tree-based device we have had our cameras in front of (https://cacophony.org.nz/another-experiment-showing-very-low-predator-trap-interaction-rates).

The reason we will keep posting data like this is that we see people suggesting they will achieve predator elimination with low interaction devices like these.  We fail to understand how this is possible. Low interaction devices are fine for reducing the cost of suppression but we don’t see any way devices with such low interaction can get total elimination. Feel free to chip in on the comments below if you have an explanation.  We're simply interpreting the data our customers are collecting using our thermal cameras.

We will keep saying as often as possible that tinkering with devices that most predators walk past is not likely to make much difference. There are lots of other more promising strategies that we would love to see more people working on (https://cacophony.org.nz/cacophony-project-strategy-and-progress-summary and https://cacophony.org.nz/why-improved-interaction-rate-holy-grail-trapping).

As always, we welcome your feedback so don't hesitate to get in touch - leave a comment below or email us at blog@cacophony.org.nz.