Making sense of the data. Part 2 – indices…


Indices, being a summary of a number of data elements, allow you to track trends over time. With large volumes of data we can develop a range of accurate indices which aren’t practically possible by field work alone – not without very significant long term field work.

There are many high quality indices which have been collected over many years such as the Breeding Bird Index. The design and management of the index and data collection is crucial to ensure a consistent good quality index.

Given we can now collect large volumes of accurate species level data at unprecedented levels – both volume and cost – reporting indices becomes straightforward even when replication current indices.

The Farmland Bird Index in the UK is primarily defined by the presence of 14 farmland bird species – Yellowhammer, Yellow Wagtail, Rook etc – so reporting the index is straightforward as shown below.

Farmland Bird Index

Other indices such as Species Richness, as illustrated at the top of the blog, are also straightforward.

Given bioacoustics will likely identify more species than a site survey, it’s possible indices reported through Wilder Sensing could achieve a higher score – so some calibration is required.