grant's blog

The Cacophony Project Strategy and Progress: A summary

If you're a regular reader of our blog, it might be easy to get the impression that we are randomly trying lots of things.  The reality of life on the project is somewhat different - there is a targeted structure to what we are doing. This post gives a summary of that strategy.  To bring back the Cacophony of native fauna in NZ there are a number of separate parts of the puzzle that we are trying to solve. What follows is a summary of each sub-goal as we see it along with an indication of where we are up to with our progress.

Blind-snap - our first crack at a high interaction predator trap

Our previous blogs have highlighted how most predators in well trapped areas just walk past existing traps. This blog shows our first attempt at a device designed to trap hard to trap predators or re-invading predators. At the moment the competition for this sort of application is pretty much manual hunting or very intense trapping and baiting (which often never gets to zero).

Why improved interaction rate is the holy grail for trapping

In recent blog posts we have gone into detail on different trapping strategies.  We chose to do this because we are convinced that many approaches that may seem intuitively to be great strategies won’t actually make much of a difference to the elimination of predators. Our camera experiments have shown consistently and across a number of different environments that, for an area that has been trapped for a while, there is a persistent population that avoids existing traps.  Today we introduce a collection of approaches and ideas that we believe can actually improve the predator interaction rate and give us a real chance of achieving our predator-free goals.

Will improving the kill rate of existing traps make much of difference in our ability to eliminate predators?

Today we tackle the question of the kill rate of existing traps.  The arsenal of traps available to trappers includes some well-designed, field-tested, and hardy workhorses.  And yet we know that even the most skillful deployment of these in the field only delivers a level of suppression, not the total elimination we strive for.  Today we discuss why that might be.

Will automatic baiting and long life lures make a difference to our ability to totally eliminate predators?

The previous blog posts showed how a simple model can help understand typical predator elimination methods. It makes intuitive sense that long life lure or automatic dispensing lures will help with trapping.  In this blog we discuss the impact of automatic lures and long life lures for their potential to achieve total predator elimination.

Will automatic resetting traps make much of a difference to our ability to totally eliminate predators?

Today we return to our core subject of eliminating predators.  If you're keen to follow our work on the fever screening device (which is now on the market), we have now launched a new website with its own blog:  All future updates on the device will appear there.

So, back to dealing with predators.  In some previous blog posts, we showed how a simple model can help understand typical trapping and poisoning methods.  Part of the goal of this model was to help understand what strategies might make the biggest difference and thus improve the chance of total predator elimination. In this blog we discuss the predictions our model makes on the impact of auto-resetting traps.


Another experiment showing very low predator trap interaction rates

The Eastern Bays Songbird project has been going for 2 years and the members were keen to see how they were getting on with their goal of predator eradication. They have been using a 2040 Thermal Camera developed by The Cacophony Project to see what is going on around their traps. Their overall impression before deploying the camera was that they were getting the predator numbers down.  They hoped the Thermal Camera would be a great way to get a full picture of the predators in the area. This camera was developed because standard trail cameras are designed for pig and deer and miss lots of the small moving mammals we are interested in here.  In this entry, we share their findings.

Effectiveness of aerial poison drops

Our previous blog post showed a simple model to allow you to work out trap interaction rates. The goal of this post is to show that this same simple model can also be used to explain the effectiveness of aerial poison drops. We are not making any comments about the value of poison drops as a tool but just showing how a simple model works for different elimination methods. We like the fact that a fairly simple tool can help explain the relative merits of different elimination methods. The real value starts to appear when we tweak some of the other parameters in the model - we think it gives us a clear idea about useful ways to improve predator elimination.

How often do predators interact with traps?

Over the last three years we have had various versions of our thermal cameras in front of all the main types of traps. What we have found is that a large number of predators seem to just walk on past irrespective of what type of lures and set ups we use. We have detailed videos of rats and possums running all around traps but not always interacting with them. Typical reaction to this is that we must be doing something wrong but after watching tens of thousands of videos we suspect this is more of an issue than just us being hopeless trappers.

Today we introduce a model we have developed to allow you to calculate the interaction rate of your traps.  Given inputs such as interaction rate, elimination rate, number of devices, and predator population the model creates a graph showing the likely impact on the population.  We think the results are not only intriguing but telling.  They suggest it might be time for all of us to adjust our view of the importance of some of the factors involved.