Rise of the machines: Integrating technology with playback experiments to study cetacean social cognition in the wild

Abstract

Cetaceans represent an evolutionary peak in terms of their cognitive capacities, complex communication systems and their structured, multilevel societies. However, the difficulty of observing their behaviour underwater means that studying whale and dolphin sociality in the wild poses some significant methodological challenges. Traditionally, playback experiments have been used to explore aspects of communication and cognition in whales and dolphins, particularly with trained animals under human care. However, while these studies have provided major breakthroughs in our understanding of cetacean social cognition, it is difficult to know whether these findings generalize to wild animals. In recent years, new state‐of‐the‐art technology (drones and non‐invasive sound and movement tags) have revolutionized the field of marine mammal behaviour, providing unparalleled information on the fine‐scale behaviour of individuals in the wild. Here, we review the state of the field, combining published studies with our own extensive experience, to demonstrate how these new technologies fundamentally change the behavioural metrics that we are able to measure; allowing us to move from categorical observations to quantifying fine‐scale changes in movement, activity and vocal behaviour. We discuss how conducting playback experiments alongside these new technologies combines rigorous experimental design with strong ecological validity and increased reproducibility and can be adapted for many social species, setting the standard for high‐calibre, field‐based experiments that explore animal social cognition in the wild.

An ethical assessment of the use of old and new methods to study sociality in wild animals

“…Typically, catching animals and releasing them has enjoyed much success as a tool to study their sociality. There is a large tradition of bird ringing (Brown & Oschadleus, 2008; see Wild et al 2022), although ‘ringing’ also extends to other larger animals such as terrestrial mammals (see Demartsev et al, 2022) and marine mammals (see King & Jensen, 2022) under various forms, collectively referred to here as tagging. Tagging may here take different forms: some animals can be caught and tagged without the need for further manipulation; other must be darted and anaesthetized to allow fitting them with a collar; finally, in some types of tagging the tag literally invades their body (Soulsbury et al, 2020).…”

“…The use of novel technologies, even with well‐habituated populations, also falls within this category. The increasing use of drones (see King & Jensen, 2022; Schad & Fischer, 2022), whether with aerial or terrestrial species, can add several layers of stress: individuals may be disturbed by the presence of a rather noisy object, or by the simple presence of an ever tracking object that remains in their vicinity. In this respect, wild animals, at least when their habitat allows it, can always lose human observers who are not as adapted to their study species environment as they are.…”

A multicomponent approach to studying cultural propensities during foraging in the wild

“…Birds and cetaceans have documented evidence of social learning in their vocalizations and song behaviours and experiments have been conducted to further tweeze out the extent of their cultural propensities (Aplin, 2019; Ford, 1991; Garland & McGregor, 2020). For these species, we suggest that combining field experiments such as audio playbacks (see King & Jensen, 2022) with the study of ecological or physiological factors can allow researchers to determine how these factors impact social learning and the transmission of behaviours.…”

Striking pay dirt: Contemporary methods for studying animal sociality in the wild

“…While tags and their development have been privileged for decades, new technology also offers much welcome new avenues of research. Echoing King and Jensen (2022), Schad and Fischer (2022) show how drones can be used to study a range of issues in individual and collective behaviour, particularly when paired with computer algorithms and automated detection software. Importantly, they also discuss the impact of drones in terms of animal disturbance, which we will come back to in our final paragraph.…”

“…Instead, ethical considerations should push researchers to develop their research protocols in view of limiting their impact on wild animals, while still extracting as much information as they can at one time, to avoid the need to re‐expose animals indefinitely. Crucially, the methods presented in this Special Feature will all facilitate this, be it by automatizing feeders (Harrison et al, 2023; Wild et al, 2022), or by making extensive use of remote sensing (He et al, 2022; King & Jensen, 2022; Mannion et al, 2022; Sarabian et al, 2023) thus showing that the study of sociality in the wild is not incompatible with the use of contemporary methods. In fact, such methods should be tested to explore the limits of their use on different species and produce reasonable do‐or‐do not guidelines that can guide the design and implementation of future research.…”