Viewing the rare through public lenses: insights into dead calf carrying and other thanatological responses in Asian elephants using YouTube videos

Abstract

Documenting the behavioural repertoire of an animal species is important for understanding that species' natural history. Many behaviours such as mating, parturition and death may be observed only rarely in the wild due to the low frequency of occurrence, short duration and the species' elusiveness. Opportunistic documentation of rare behaviours is therefore valuable for deciphering the behavioural complexity in a species. In this context, digital platforms may serve as useful data sources for studying rare behaviours in animals. Using videos uploaded on YouTube, we document and construct a tentative repertoire of thanatological responses (death-related behaviours) in Asian elephants (Elephas maximus). The most frequently observed thanatological responses included postural changes, guarding/keeping vigil, touching, investigating the carcass, epimeletic behaviours and vocalizations. We also describe some infrequently observed behaviours, including carrying dead calves by adult females, re-assurance-like behaviours and attempts to support dying or dead conspecifics, some of which were only known anecdotally in Asian elephants. Our observations indicate the significance of open-source video data on digital platforms for gaining insights into rarely observed behaviours and support the accumulating evidence for higher cognitive abilities of Asian elephants in the context of comparative thanatology.

Keywords: Elephas maximus; YouTube; carcass carrying; death reactions; rare behaviour; thanatology.

Figure 1.

Illustrations showing (a) dead calf carrying behaviour and (b) some of the other visual (to the assessors) thanatological responses (change in posture, exploratory, epimeletic, touches, guarding/vigil, vocalizations and social behaviours). (Illustrations by S.S.P.)

Figure 2.

Doughnut charts representing total recorded thanatological cases (presented as numbers) in terms of (a) animal status, (b) country where the cases were reported from, (c) the cause of deaths and (d) presence of humans.

Figure 3.

Dead calf carrying by adult female wild Asian elephants (n = 5 cases out of 25 total cases) and African elephant. These still images were retrieved from (a) Video 1 (channel: monismukhtar1), (b) Video 21 (channel: ETV Bharat English; Case #11), (c) Video 28 (channel: Buzz news; Case #16), (d) Video 35 (channel: Lanka Wild Safari; Case #22) and (e) Video 40 (non-YouTube data: from co-author R.S., data archive; Case #25; refer to electronic supplementary material, table S1, for more details). For comparative documentation, we provide a still image (f) from a 44 s long video of an African female elephant holding a dead calf by her tusk and trunk at the Lake Manyara National Park, Tanzania (clip source: Fay Amon, 29 August 2021; Facebook; https://fb.watch/aMDA94fK_z/).

Figure 4.

Frequency of visible thanatological responses. (a) Separated bar graph represents the relative frequency (%) of thanatological reactions observed in all 25 cases. (b) Bar plots represent some of the visual thanatological responses including: (i) changes in body posture, (ii) touch, (iii) exploratory, (iv) guarding/vigil, (v) audible vocal and non-vocal signals and (vi) epimeletic behaviours. The x-axes in (b) represent different types of responses and the y-axes (different scales for each plot) represent the frequency of occurrences of these reactions across all cases.