Fewer bat passes are detected during small, commercial drone flights

AbstractAdvances in technological capabilities, operational simplicity and cost efficiency have promoted the rapid integration of unmanned aerial vehicles (UAVs) into ecological research, providing access to study taxa that are otherwise difficult to survey, such as bats. Many bat species are currently at risk, but accurately surveying populations is challenging for species that do not roost in large aggregations. Acoustic recorders attached to UAVs provide an opportunity to survey bats in challenging habitats. However, UAVs may alter bat behaviour, leading to avoidance of the UAV, reduced detection rates and inaccurate surveys. We evaluated the number of bat passes detected with and without the presence of a small, commercial UAV in open habitats. Only 22% of bat passes were recorded in the presence of the UAV (0.23 ± 0.09 passes/min) compared to control periods without the UAV (1.03 ± 0.17 passes/min), but the effect was smaller on the big brown bat/silver-haired bat (Eptesicus fuscus/Lasionycteris noctivagans) acoustic complex. Noise interference from the UAV also reduced on-board bat detection rates. We conclude that acoustic records attached to UAVs may inaccurately survey bat populations due to low and variable detection rates by such recorders.

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Approaching birds with drones: first experiments and ethical guidelines

Biology Letters ◽

10.1098/rsbl.2014.0754 ◽

2015 ◽

Vol 11 (2) ◽

pp. 20140754 ◽

Cited By ~ 100

Author(s):

Elisabeth Vas ◽

Amélie Lescroël ◽

Olivier Duriez ◽

Guillaume Boguszewski ◽

David Grémillet

Keyword(s):

Best Practices ◽

Unmanned Aerial Vehicles ◽

Ecological Research ◽

Ethical Guidelines ◽

Wetland Area ◽

Physiological Indicators ◽

Approach Distance ◽

Aerial Vehicles ◽

Approach Speed ◽

The Impact

Unmanned aerial vehicles, commonly called drones, are being increasingly used in ecological research, in particular to approach sensitive wildlife in inaccessible areas. Impact studies leading to recommendations for best practices are urgently needed. We tested the impact of drone colour, speed and flight angle on the behavioural responses of mallards Anas platyrhynchos in a semi-captive situation, and of wild flamingos ( Phoenicopterus roseus ) and common greenshanks ( Tringa nebularia ) in a wetland area. We performed 204 approach flights with a quadricopter drone, and during 80% of those we could approach unaffected birds to within 4 m. Approach speed, drone colour and repeated flights had no measurable impact on bird behaviour, yet they reacted more to drones approaching vertically. We recommend launching drones farther than 100 m from the birds and adjusting approach distance according to species. Our study is a first step towards a sound use of drones for wildlife research. Further studies should assess the impacts of different drones on other taxa, and monitor physiological indicators of stress in animals exposed to drones according to group sizes and reproductive status.

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The method of maximum plausibility in the problems of protection of the radio signal of unmanned aerial vehicles control

Modern information security ◽

10.31673/2409-7292.2020.041217 ◽

2020 ◽

Vol 44 (4) ◽

Author(s):

S. I. Ganusyak ◽

Keyword(s):

Unmanned Aerial Vehicles ◽

Radio Signal ◽

Harmonic Oscillation ◽

Radio Communication ◽

Noise Interference ◽

Communication Signal ◽

Aerial Vehicles ◽

Proposed Model ◽

Method Of Maximum Likelihood ◽

Aerial Vehicle

The paper considers the problem of protection of control of the radio signal of control of unmanned aerial vehicles as a task of control of signal parameters. The problem of control of a parameter of a radio signal and a problem of protection against interception by control of the unmanned aerial vehicle is formulated. The methods of estimating the parameters of the radio communication signal are analyzed and the method of estimating the parameters based on the method of maximum likelihood is proposed. This technique is demonstrated by estimating the phase of harmonic oscillation, which describes the radio signal and there are noise interference. Simulation modeling of the developed method is carried out, which confirmed the adequacy of the proposed model.

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Attitude controller design of mini-unmanned aerial vehicles using fuzzy sliding-mode control degraded by white noise interference

IET Control Theory and Applications ◽

10.1049/iet-cta.2011.0240 ◽

2012 ◽

Vol 6 (9) ◽

pp. 1205 ◽

Cited By ~ 19

Author(s):

F.-K. Yeh

Keyword(s):

Sliding Mode Control ◽

White Noise ◽

Unmanned Aerial Vehicles ◽

Controller Design ◽

Sliding Mode ◽

Fuzzy Sliding Mode Control ◽

Noise Interference ◽

Aerial Vehicles ◽

Fuzzy Sliding Mode ◽

Attitude Controller

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Przewalski’s Horses (Equus ferus przewalskii) Responses to Unmanned Aerial Vehicles Flights under Semireserve Conditions: Conservation Implication

International Journal of Zoology ◽

10.1155/2021/6687505 ◽

2021 ◽

Vol 2021 ◽

pp. 1-6

Author(s):

Vanessa Lu ◽

Feng Xu ◽

Mardan Aghabey Turghan

Keyword(s):

Unmanned Aerial Vehicles ◽

Behavioral Responses ◽

Technological Innovations ◽

Wildlife Monitoring ◽

Ecological Research ◽

Flight Altitude ◽

Strong Correlations ◽

Natural Behavior ◽

Aerial Vehicles ◽

Future Viability

Recent technological innovations have led to an upsurge in the availability of unmanned aerial vehicles (also known as drones and hereafter referred to as UAVs)—aircraft remotely operated from the ground—which are increasingly popular tools for ecological research, and the question of this study concerns the extent to which wildlife responses might allow aerial wildlife monitoring (AWM) by UAVs. Our experiment tests the hypothesis that the wildlife-UAVs interaction depends strongly on flight altitude that there may be a lowest altitude range for which the ungulates are not exceedingly disturbed, dictating a practically achievable level of discernibility in flight observation, for this question might influence the future viability of the UAVs in the study and protection of the other wildlife in China’s semiarid ecosystem. We examined the behavioral responses of a group of enclosed Przewalski’s horses (Equus ferus przewalskii) to the presence of different in-flight UAVs models by conducting flights at altitudes ranging from 1 to 52 meters and recorded the heights at which each horse reacted to (noticed and fled) the UAVs. All horses exhibited a stress response to UAVs flights as evidenced by running away. The results suggest strong correlations between flight altitude and response across the different subjects that adults generally noticed the UAVs at the larger heights (20.58 ± 10.46 m) than the immature (4.67 ± 0.87 m). Meanwhile, reaction heights of females (15.85 ± 6.01 m) are smaller than that of males (26.85 ± 18.52 m). Supported by their biological roles in herds (e.g., males must give protection to his entire herd while females are purely responsible for their offspring), our results also show that age, closely followed by gender, are the two most significant elements that determine a horse’s level of alertness to the UAVs. This research will help future scientists to better gauge the appropriate height to use a drone for animal observation in order to minimize disturbance and best preserve their natural behavior.

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Development of thickened semi-synthetic engine oil M-5z / 20 AERO for four-stroke gasoline engines aircraft piston of unmanned aerial vehicles (UAVs)

World of OIL Products the Oil Companies Bulletin ◽

10.32758/2071-5951-2020-0-6-44-47 ◽

2020 ◽

Vol 06 ◽

pp. 44-47

Author(s):

A.A. Moykin ◽

◽

A.S. Medzhibovsky ◽

S.A. Kriushin ◽

M.V. Seleznev ◽

...

Keyword(s):

Unmanned Aerial Vehicles ◽

Engine Oil ◽

Motor Oil ◽

Gasoline Engines ◽

State Research Institute ◽

Technical Requirements ◽

Aerial Vehicles ◽

State Research ◽

Industrial Batch ◽

The Russian Federation

Nowadays, the creation of remotely-piloted aerial vehicles for various purposes is regarded as one of the most relevant and promising trends of aircraft development. FAU "25 State Research Institute of Chemmotology of the Ministry of Defense of the Russian Federation" have studied the operation features of aircraft piston engines and developed technical requirements for motor oil for piston four-stroke UAV engines, as well as a new engine oil M-5z/20 AERO in cooperation with NPP KVALITET, LLC. Based on the complex of qualification tests, the stated operational properties of the experimental-industrial batch of M-5z/20 AERO oil are generally confirmed.

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