Figure - available from: Wildlife Biology
This content is subject to copyright. Terms and conditions apply.
Source publication
Manned, aerial surveys are an important tool for wildlife managers, but they are dangerous to conduct, expensive and difficult to replicate. Interest is increasing in using small unmanned aerial systems [sUAS] due to concerns associated with traditional manned, aerial surveys. To assess the potential of sUAS technology for grouse lek surveys, we ex...
Citations
... Variables used in this model were treatment (flown or control), average temperature during survey time, average wind speed during survey, cloud cover (clear, partly cloudy, mostly cloudy, and overcast), wind direction (8 categories of N, S, E, W, NE, NW, SE, SW), wetland cover type [22], UAV survey size (area coverage of programmed flight) to represent wetland size, and launch distance (Euclidean distance of edge of wetland to UAV launch site). We included wind parameters because the UAV might have a higher noise output with high winds and birds might respond differently [23]. To explore if ducks responded differently to shadows produced from the UAV, we included cloud cover in the model. ...
Unmanned aerial vehicles (UAVs) have become a popular wildlife survey tool. Most research has focused on detecting wildlife using UAVs with less known about behavioral responses. We compared the behavioral responses of breeding blue-winged teal ( Spatula discors ) (n = 151) and northern shovelers ( Spatula clypeata ) (n = 46) on wetlands flown over with a rotary DJI Matrice 200 quadcopter and control wetlands without flights. Using a GoPro camera affixed to a spotting scope, we conducted focal individual surveys and recorded duck behaviors for 30 minutes before, during, and 30 minutes after UAV flights to determine if ducks flushed or changed in specific activities. We also conducted scan surveys during flights to examine flushing and movement on the entire wetland. Between 24 April and 27 May 2020, we conducted 42 paired (control and flown) surveys. Both teal and shovelers increased proportion of time engaged in overhead vigilance on flown wetlands from pre-flight to during flight (0.008 to 0.020 and 0.006 to 0.032 of observation time, respectively). Both species left the wetland more frequently during flights than ducks on control wetlands. Despite similarities between species, we observed marked differences in time each species spent on active (e.g., feeding, courtship, swimming), resting, and vigilant behaviors during flights. Overall, teal became less active during flights (0.897 to 0.834 of time) while shovelers became more active during this period (0.724 to 0.906 of time). Based upon scan surveys, ducks flushed in 38.1% of surveys while control wetlands only had a single (2.4%) flush during the flight time. We found launch distance was the most important predictor of whether ducks swam for cover or away from the UAV which could result in inaccurate counts. Ducks appear aware of UAVs during flights, but minimal behavioral shifts suggest negative fitness consequences are unlikely.
... Multiple commercial sUAS models and sensors are available and vary in their usefulness by survey goals and situations [10,16]. For example, sUAS models (e.g., DJI Matrice 600 Pro) may be chosen based on platform type (e.g., fixed-wing or multirotor), ease of use, payload capacity to carry the desired sensor, or cost [4], and sensors may be chosen based on what type of remotely sensed data are desired and survey conditions (e.g., optical sensors for determining animal behavior; see [24]; or thermal sensors for detecting cryptic nocturnal animals; see [25]). 'Off-the-shelf ' sUAS packages further support widespread use of sUAS and exploration of new applications [16]. ...
Background
Small unmanned aircraft systems (sUAS) are replacing or supplementing manned aircraft and ground-based surveys in many animal monitoring situations due to better coverage at finer spatial and temporal resolutions, access, cost, bias, impacts, safety, efficiency, and logistical benefits. Various sUAS models and sensors are available with varying features and usefulness depending on survey goals. However, justification for selection of sUAS and sensors are not typically offered in published literature and existing reviews do not adequately cover past and current sUAS applications for animal monitoring nor their associated sUAS model and sensor technologies, taxonomic and geographic scope, flight conditions and considerations, spatial distributions of sUAS applications, and reported technical difficulties. We outline a systematic map protocol to collect and consolidate evidence pertaining to sUAS monitoring of animals. Our systematic map will provide a useful synthesis of current applications of sUAS-animal related studies and identify major knowledge clusters (well-represented subtopics that are amenable to full synthesis by a systematic review) and gaps (unreported or underrepresented topics that warrant additional primary research) that may influence future research directions and sUAS applications.
Methods
Our systematic map will investigate the current state of knowledge using an accurate, comprehensive, and repeatable search. We will find relevant peer-reviewed and grey literature as well as dissertations and theses using online publication databases, Google Scholar, and by request through a professional network of collaborators and publicly available websites. We will use a tiered approach to article exclusion with eligible studies being those that monitor (i.e., identify, count, estimate, etc.) terrestrial vertebrate animals. Extracted data concerning sUAS, sensors, animals, methodology, and results will be recorded in Microsoft Access. We will query and catalogue evidence in the final database to produce tables, figures, and geographic maps to accompany a full narrative review that answers our primary and secondary questions.
... Taxa 58 Drever et al. 2015;Dulava et al. 2015;Pomeroy et al. 2015;Junda et al. 2016;Kidawa et al. 2016;Marine Mammal Commission 2016;Scobie and Hugenholtz 2016;Smith et al. 2016;Adame et al. 2017;Borrelle and Fletcher 2017;Brisson-Curadeau et al. 2017;Erbe et al. 2017;Fiori et al. 2017;Gonzalez and Johnson 2017;Mustafa et al. 2017Mustafa et al. , 2018Albores-Barajas et al. 2018;Arona et al. 2018;Barnas et al. 2018a;Bevan et al. 2018;Domínguez-Sánchez et al. 2018;Egan 2018;Lyons et al. 2018Lyons et al. , 2019bMcIntosh et al. 2018;Ramos et al. 2018;Raoult et al. 2018Raoult et al. , 2020Rees et al. 2018;Rümmler et al. 2018;Rush et al. 2018;Thompson et al. 2018;Valle and Scarton 2018Wallace et al. 2018;Weimerskirch et al. 2018;Barnas 2019;Bennitt et al. 2019;Brunton et al. 2019;Burke et al. 2019b;Fettermann et al. 2019;Harris et al. 2019;Adams et al. 2020;Barr et al. 2020;Bech-Hansen et al. 2020;Jarrett et al. 2020;Lachman et al. 2020;Mapes et al. 2020;Mesquita et al. 2020;Rexer-Huber and Parker 2020;Rischette et al. 2020;Schroeder et al. 2020;Weston et al. 2020;Dundas et al. 2021;Giles et al. 2021;Pfeifer et al. 2021 Visual acuity 1 Mesquita et al. 2020 Auditory acuity Mesquita et al. 2020). We found 28 studies that deployed statistical models to differentiate animal activity patterns during drone flights and in the absence of drones (control). ...
... Of the 81 publications that referenced noise emissions, six also referenced sudden changes in noise intensity (Table 1). These changes in noise intensity were attributed to flight angles; for example, two publications noted greater noise emissions from their drone during vertical ascents compared to horizontal passes (Mustafa et al. 2017;Weston et al. 2020), and Rischette et al. (2020) found that their drone was forced to increase its flight angle during high winds in order to maintain a linear flight path, during which higher noise emissions resulted. ...
... First, as discussed earlier, Ditmer et al. (2015) recorded more elevated heart rates in American Black Bears during drone flights in windy conditions. Second, Rischette et al. (2020) found different effects of windspeed in their study of Sharp-tailed Grouse Tympanuchus phasianellus; windspeeds between 6-13 km per hour were optimal for minimising flushing during drone flights, possibly because lower windspeeds caused noise emissions from drones to be more easily perceived by grouse while higher windspeeds forced an increase in flight angle in order to maintain a linear flight path, causing their drone to emit more noise. In contrast, three other research studies found that windspeed had no statistically significant effect on responses to drones in Adélie and Gentoo Penguins Pygoscelis papua (Rümmler et al. 2016;Mustafa et al. 2017), Common Bottlenose Dolphins and Antillean Manatees (Ramos et al. 2018). ...
Drones are a modern alternative to manned aircraft for aerial surveys, however approaching wildlife with drones may still cause disturbance. Understanding the factors influencing animal responses to drone flights is fundamental for informing guidance on lowest-impact flight practices. We reviewed scientific literature on drone flights conducted to approach wildlife and collated and quantified references to factors that should be considered in the development of guidelines and policies. The most referenced controllable factors were approach distance, noise emissions and airspeed. Other frequently referenced controllable factors included drone type, take-off distance, flight pattern, pilot experience and competence, whether consecutive flights were conducted and flight duration. The most referenced environmental factors were animal taxa, biological state of animals and ambient noise, followed by whether conspecifics are present, weather variables, habitat variables, whether animals have received previous exposure to anthropogenic settings, animals’ behaviour prior to drone flights and whether predators are present. Policies and protocols that address these factors have an increased probability of minimising disturbance of drone flights. The variability in animal responses across different taxa, different ways drone flights are performed and the different circumstances they are deployed in highlights the need for taxa-specific protocols that also account for geographical and biological variations.
Unmanned aerial vehicles (UAVs), or drones, are being utilized by wildlife biologists to monitor populations of birds and mammals. However, the reaction of wildlife to drones varies by species, so a preliminary evaluation must be conducted to determine if the target species can be detected via drone footage and to determine how the target species will react to drone presence. Lek‐mating prairie‐chickens (Tympanuchus spp.) seem amenable to drone‐based surveys because they are relatively large and display in groups on elevated sites with sparse vegetation. The goal of our study was to determine what flight characteristics maximize prairie‐chicken detection on drone video footage, to document the birds' reactions to the drones, and to compare how the noise produced by the drones compares to ambient sounds. We tested 3 sizes of rotary‐winged drones, flown at 3 heights, with 3 different camera angles by flying over known prairie‐chicken leks. We determined that >65% of prairie‐chickens present were detected using video footage at a height of 100 m with a 10° camera angle. Drones of different sizes had similar detectability. However, observers in blinds adjacent to leks routinely detected more birds than were detected on drone footage (detection on drone footage was 39.7 ± 9.6% of birds present). Prairie‐chickens flushed in 96% of trials when a drone was flown over display locations. Time to return to the lek following drone disturbance was similar to prairie‐chickens' reactions to natural predators. Prairie‐chickens flushed when drone sound levels were comparable to ambient noise. Developing guidelines for the ethical use of drones in wildlife research will require quantifying the amount of taxa‐specific disturbance caused by drones. Our study begins to close this knowledge gap by documenting disturbance to upland, lek‐mating grouse of conservation concern, and suggests that the focal species' reaction to aerial predators may provide clues as to how that species may react to drones. Before drones (umanned aerial vehicles) can replace manned aircraft in wildlife surveys, best practices need to be developed that maximize the data obtained while minimizing disturbance to the focal wildlife. Our study contributes to the development of best practices for the use of drones for monitoring populations of upland, lek‐mating grouse of conservation concern, and provides recommendations for optimal drone size, camera angle, and height of flight for maximizing detection.
Drones or unoccupied aerial vehicles are rapidly being used for a spectrum of applications, including replacing traditional occupied aircraft as a means of approaching wildlife from the air. Though less intrusive to wildlife than occupied aircraft, drones can still cause varying levels of disturbance. Policies and protocols to guide lowest-impact drone flights are most likely to succeed if considerations are derived from knowledge from scientific literature. This study examines trends in the scientific literature on using drones to approach wildlife between 2000 and 2020, specifically in relation to the publication types, scientific journals that works are published in, purposes of drone flights reported, taxa studied, and locations of studies. From 223 publications, we observed a large increase in relevant scientific literature, the majority of which were peer-reviewed articles published across 86 scientific journals. The largest proportion of peer-reviewed research articles related to aquatic mammals or aquatic birds and the use or trial of drone flights for conducting population surveys, animal detection, or investigations of animal responses to drone flights. The largest proportion of articles were studies conducted in North America and Australia. Since animal responses to drone flights vary among taxa, populations, and geographic locations, we encourage further growth in the volume of relevant scientific literature needed to inform policies and protocols for specific taxa and (or) locations, particularly where knowledge gaps exist.
Drones are becoming more accessible and efficient. This article presents a review of recent scientific literature focusing on their use to study wildlife. The 250 publications consulted were grouped into one of 4 categories: wildlife surveys, the behavioural response of wildlife to drones, the study of wildlife behaviour and wildlife protection. The review highlighted the great potential of drones for helping in the survey of animals, especially birds and mammals, and it also revealed the developments underway to allow their use for studying aquatic fauna, amphibians, reptiles and insects. The main impacts of drones on animals are presented and, based on the available information, preliminary recommendations are made to limit their disturbance to wildlife. Drones have multiple advantages and the rapid development of this technology suggests that several of the current limits to their use will soon be overcome. Finally, elements of the Canadian regulations on the use of drones are presented. In conclusion, in the medium-term, drones have the potential to play a significant role in the protection and management of biodiversity.
