Iguanas from Above: New Airborne Approaches to Population Surveying

The marine iguana (Amblyrhynchus cristatus) is an iconic endangered species of the Galapagos archipelago which faces mounting anthropogenic threats. During the last three decades, much has been learned about the species from an ecological and evolutionary perspective. However — due to significant logistical constraints — baseline data on population sizes, health, and locations across the archipelago are lacking; this severely impedes both conservation and research efforts. In this presentation, I will introduce our current project “Iguanas from Above” which is pioneering the use of drones, flown from boats, to collect aerial images above marine iguana colonies. This new approach has been validated against traditional ground-based survey methods, such as simple counts and Capture-Mark-Resight. I will also discuss our use of citizen scientists in data analysis, showing that — with sufficient image quality — online volunteers can reliably find and count marine iguanas. Finally, I will share the next stages of the work, including preliminary insights from the use of Machine Learning for image analysis, and discuss further applications for the approach.