Seabird species vary in behavioural response to drone census

This is the final version of the article. Available from the publisher via the DOI in this record.Unmanned aerial vehicles (UAVs) provide an opportunity to rapidly census wildlife in remote areas while removing some of the hazards. However, wildlife may respond negatively to the UAVs, thereby skewing counts. We surveyed four species of Arctic cliff-nesting seabirds (glaucous gull Larus hyperboreus, Iceland gull Larus glaucoides, common murre Uria aalge and thick-billed murre Uria lomvia) using a UAV and compared censusing techniques to ground photography. An average of 8.5% of murres flew off in response to the UAV, but >99% of those birds were non-breeders. We were unable to detect any impact of the UAV on breeding success of murres, except at a site where aerial predators were abundant and several birds lost their eggs to predators following UAV flights. Furthermore, we found little evidence for habituation by murres to the UAV. Most gulls flew off in response to the UAV, but returned to the nest within five minutes. Counts of gull nests and adults were similar between UAV and ground photography, however the UAV detected up to 52.4% more chicks because chicks were camouflaged and invisible to ground observers. UAVs provide a less hazardous and potentially more accurate method for surveying wildlife. We provide some simple recommendations for their use.We thank T. Leonard and the Seabird Ecological Reserves Advisory Committee for permission to work at Witless Bay, the Canadian Wildlife Service for permits to work at Newfoundland and Nunavut and the Government of Nunavut for permits to work in Nunavut. Newfoundland and Labrador Murre Fund, Bird Studies Canada and the Molson Foundation directly funded the work. An NSERC Discovery Grant, the Canada Research Chair in Arctic Ecology and Polar Continental Shelf Project also helped fund the project. We thank T. Burke, G. Sorenson, T. Lazarus and M. Guigueno for their help and J. Nakoolak for keeping us safe from bear

Optimisation of UAVs‐SfM data collection in aeolian landform morphodynamics : a case study from the Gonghe Basin, China

UAVs‐SfM (Unmanned Aerial Vehicles‐ Structure from Motion) systems can generate high‐resolution 3D topographic models of aeolian landforms. To explore the optimisation of UAVs‐SfM for use in aeolian landform morphodynamics, this study tested flight parameters for two contrasting aeolian landform areas (free dune and blowout) to assess the 3D reconstruction accuracy of the UAVs survey compared with field point measurements using differential RTK‐GPS (Real‐time Kinematic‐Global Positioning System). The results reveal the optimum UAVs‐SfM flight set‐up at the free‐dune site was: flying height = 74 m, camera tilt angle = ‐90°, photo overlap ratio = 85%/70% (heading/sideways). The horizontal/vertical location error was around 0.028~0.055 m and 0.053‐0.069 m respectively, and a point cloud density of 463/m3 was found to generate a clear texture using these flying parameters. For the <20m deep blowout the optimum set‐up with highest accuracy and the lowest cliff texture distortion was: flying height = 74 m combined camera tilt angle = ‐90° and ‐60°, photo overlap ratio = 85%/70% (heading/sideways), and an evenly distributed GCPs (Ground Control Points) density of 42/km2 using these flying parameters. When the depth of the blowouts exceeded 40 m, the optimum flight/survey parameters changed slightly to account for more challenging cliff texture generation: flying height = 80 m (with ‐90° and ‐60°combined camera tilt angle), GCPs density = 63/km2 to generate horizontal and vertical location error of 0.024 m and 0.050 m respectively, and point cloud density of 2597.11/m3. The main external factors that affect the successful 3D reconstruction of aeolian landforms using UAVs‐SfM are the weather conditions, manipulation errors, and instrument system errors. The UAVs‐SfM topographic monitoring results demonstrate that UAVs provide a viable and robust means for aeolian landform morphodynamics monitoring. Importantly, the rapid and high precision 3D reconstruction processes were significantly advanced using the optimal flight parameters reported here

Use of drones for research and conservation of birds of prey

In the last two decades, unmanned aircraft systems (UASs) have experienced an exponential development. Originally conceived for military use, technological advances and a dramatic reduction of prices are leading to widespread use of UASs in environmental disciplines including remote sensing, ecology, wildlife management or environmental monitoring (Chabot and Bird 2015; Linchant et al. 2015; Christie et al. 2016).Fil: Canal Piña, David. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Superior de Investigaciones Científicas; EspañaFil: Negro Balmaseda, Juan José. Consejo Superior de Investigaciones Científicas; Españ