Geomorphic changes of a coral shingle cay measured using Kite Aerial Photography

• Kite Aerial Photography (KAP) was used to study changes on a coral shingle cay.
• Methods developed for measuring both topographic and sediment texture changes
• Changes quantified in context of storm activity at One Tree Island, GBR Australia
• KAP/Structure-from-motion provided a low-cost and accurate means of studying change.
• First time these techniques have been applied for measuring change in coral reefs.

Measurements of geomorphic change in the intertidal zones of coral reefs are made using a variety of remote sensing and in-situ techniques, where variations in the coverage and spatial-temporal precision achieved are directly related to the cost of data acquisition. We present a novel, low-cost technique for measuring high-resolution changes in reef environments based on Kite Aerial Photography (KAP) and photogrammetry/structure-from-motion post-processing. KAP images are used to measure fine-scale changes in intertidal topography and sediment texture characteristics, including rubble particle size, of a coral shingle cay at One Tree Island, Great Barrier Reef in the context of storm activity. Validation using Real Time Kinematic DGPS demonstrates the ability to measure topographic elevation with an error of 5.53 cm (RMSE) and a spatial resolution of 5 cm per point, an accuracy/resolution that is superior to airborne LiDAR and equivalent to terrestrial LiDAR, but at a fraction of the equipment cost.