Mapping of mudflats with UAV images in La Bocana de Iscuandé, Colombian Pacific coast

Abstract

Conservation planning for marine-coastal environments requires updated and detailed maps; the aim of this work is to generate detailed maps for two mudflats in the Iscuandé River Delta (Bocana de Iscuandé) in the Colombian Pacific Coast (Department of Nariño). These are important areas for fauna, especially migratory shorebirds. To address this problem, this study investigated the use of unmanned aerial vehicles (UAVs) as an alternative for collecting detailed mapping information in areas of difficult access using photogrammetric methodsand a geographic information system (GIS). UAV images were used to generate maps with a high level of detail at a scale of 1:10,000 that include detailed information about environments such as mudflats and mangroves which had not been mapped before. UAVs are a practical tool for mapping places where weather and access conditions hinder the use of satellite images or conventional aerial photography. They are also useful for mapping areas with high temporal and spatial variability, such as mudflats, where other platforms may not reveal their short-term dynamics. Our results show that this technique has a high potential for mapping such environments, and reveal that the Iscuandé mudflats aremaintained by a relative equilibrium between the ebb and flow of waves and tides, and are also influenced by the local climate. This type of application provides critical data for conservation and management strategies of areas with great ecological importance.