A small unmanned aerial system for estimating abundance and size of Antarctic predators

Abstract

Quantifying the distribution and abundance of predators is integral to many ecological studies, but can be difficult in remote settings such as Antarctica. Recent advances in the development of unmanned aerial systems (UAS), particularly vertical takeoff and landing (VTOL) aircraft, have provided a new tool for studying the distribution and abundance of predator populations. We detail our experience and testing in selecting a VTOL platform for use in remote, windy, perennially overcast settings, where acquiring cloud-free high-resolution satellite images is often impractical. We present results from the first use of VTOLs for estimating abundance, colony area, and density of krilldependent predators in Antarctica, based upon 65 missions flown in 2010/2011 (n = 28) and 2012/2013 (n = 37). We address concerns over UAS sound affecting wildlife by comparing VTOL-generated noise to ambient and penguingenerated sound. We also report on the utility of VTOLs for missions other than abundance and distribution, namely to estimate size of individual leopard seals. Several characteristics of small, battery-powered VTOLs make them particularly useful in wildlife applications: (1) portability, (2) stability in flight, (3) limited launch area requirements, (4) safety, and (5) limited sound when compared to fixed-wing and internal combustion engine aircraft. We conclude that of the numerous UAS available, electric VTOLs are among the most promising for ecological applications.

The Use of Unmanned Aerial Systems in Marine Mammal Research

“…The authors suggest that flying at 35-40 m above the surface level allows the gathering of important information about size, health, and behavior, while reducing disturbance levels and increasing the measurement precision if compared with manned aircraft [9]. Image resolution (<1.4 cm/pixel with 25 mm lens at 35 m altitude) was slightly lower than what was achieved by Goebel et al [8], but enough to discriminate individuals and detect changes of their body condition during subsequent encounters [9].…”

“…Perryman et al [48] and Goebel et al [8] investigated the use of a small customized hexacopter (APH-22) in the abundance estimation of seals in Antarctica. High-resolution (<1 cm/pixel with 45 mm lens at 45 m altitude) images of the shore were used to count individuals and discriminate pups from adults in fur seal (Arctocephalus gazella) and Weddell seal (Leptonychotes weddellii) colonies.…”

“…In particular, UAS have been proposed as a tool for marine mammal surveys, as they allow researchers to reach remote areas and observe animals from an advantageous perspective, being less invasive than standard aircraft [3][4][5][6][7][8][9]. Despite the challenges of operating at sea [10], UAS have been used for a number of marine mammal research applications, from abundance surveys [8,[11][12][13][14][15][16][17] to the measurement of…”

An Economical Custom-Built Drone for Assessing Whale Health

“…UAVs also provide an alternative, safer, quieter and often cost-effective option for monitoring fauna and flora, from individuals and populations to entire ecosystems, and in so doing are replacing expensive manned systems such as helicopters and fixed-wing aircraft Christie et al, 2016). UAV applications in wildlife research now encompass almost all environments, from arid deserts, through rainforests, oceans to polar regions (Linchant et al, 2013(Linchant et al, , 2015Durban et al, 2015;Goebel et al, 2015;Duffy et al, 2017).…”

“…Some examples include, counting elephants (Loxodonta africana) (Linchant et al, 2013;Vermeulen et al, 2013), UAV surveillance (anti-poaching tools) for elephants and rhinoceros (Diceros bicornis and Ceratotherium simum) (Marks, 2014;MuleroPázmány et al, 2014;Hahn et al, 2017), locating chimpanzee nests (Pan troglodytes) (van Andel et al, 2015) and mapping Sumatran orangutan (Pongo abelii) habitat, distribution and density Szantoi et al, 2017). UAV applications now extend to the polar regions where they have been used to monitor and estimate abundance of penguin populations (gentoo, Pygoscelis papua, and chinstrap, Pygoscelis antarctica) and estimate size and condition of leopard seals (Hydrurga leptonyx) (Goebel et al, 2015;Ratcliffe et al, 2015). In the marine environment, UAVs are revolutionizing the way marine species can be studied due to their small size, apparent minimal disturbance of wildlife and improved safety for both operators and animals (Nowacek et al, 2016;Fiori et al, 2017).…”