The first version of the Cacophony Index is now live. The Cacophony Project was first started to attempt to answer a seemingly simple question: "is a bird population getting better or worse over time?". We now have a tool available which can start to answer this question.
The Cacophony Index is a measure of the amount of bird song detected in the audio recordings gathered by the Cacophony Project's Bird Monitors. The Index is a number between 0 and 100 where a higher number means that more bird calls were detected. By making regular recordings for a given location, it's possible to start to see trends in bird calls over time, and also the impact of factors such as seasons and weather. Measuring bird populations is an important part of the predator free challenge because it lets us know if predator management strategies are working.
If you'd like to know more about the Cacophony Index, there are two blog articles which go into more detail.
- Chris Blackbourn, the engineer behind the Cacophony Index algorithm, describes his approach in Engineering in the Native Forest.
- Shaun Ryan from 2040 describes how you can access the Cacophony Index and what's coming next in his article.
Note that this is only the first version of the Cacophony Index. Our analysis techniques will continue to improve and can be reapplied to historical audio recordings (which are permanently stored). The most important thing is that we start collecting a steady stream recordings now from all around New Zealand to allow predator eradication efforts to be measured.