Wild Cycad Conservancy (WCC) is working with several partners to test the use of drones and allied technologies for cycad conservation planning and action. As one example, we are collaborating with the Selati Wilderness Foundation, Dr Andrew Davies from Harvard University and Integrated Aerial Systems (IAS) to test the use of drones with RGB and LiDAR sensors for surveying and mapping cycad populations.

RGB sensors capture images by combining red, green and blue light to provide detailed colour images. Light Detection and Ranging (LiDAR) measures reflected light to examine the earth’s surface and allows for high precision 3-D modelling and vegetation analysis.

Testing the tech

The Lillie Cycad (Encephalartos dyerianus) is an ideal test case – it is Critically Endangered and a high priority species for monitoring. We also have good ground-based data from population counts undertaken by the Limpopo Department of Economic Development, Environment and Tourism (LEDET) and recently updated with support from WCC. This makes it possible to compare and integrate results from ground-based surveys with high-resolution drone imagery and LiDAR data. 

The first step, using the RGB sensor, was completed by IAS in November 2024. Multiple images, taken by a drone flying along a designated flightpath at 110m above ground, have been collated and transformed into a high resolution 3-D model of the area. Artificial intelligence (AI) models were then trained to detect cycads in the aerial imagery, providing precise information on the location and numbers of plants that could be detected from the air. 

Exciting finds

Initial analyses show a close alignment between the numbers detected by AI and those counted in ground surveys, and this will be confirmed by more detailed comparisons over the next few months. We don’t expect a perfect match: small plants and offsets may be obscured by the crowns of larger plants, but this study will show what can be achieved using drone imagery. 

The LiDAR surveys should be completed before the end of January 2025 and will add more textured information on the vegetation structure and habitat, leading to a better understanding of why this species occurs only in this location and what opportunities exist for introductions to other locations nearby. 

Watch this space for more exciting developments.

Counting and measuring cycad stems.