Results
We report four calf burial cases in different tea gardens in the study area (figure 1). We present the findings in two sections, through (1) internal examination through postmortem examination report and (2) external examination and field anecdotes.
Internal examination through postmortem report (see table 1):
External examination and Field anecdotes:
The most contrasting finding of this study is the positioning of elephant carcasses during burial. In all four cases, the legs were upright, and the head, trunk, and dorsal parts were fully buried. Due to the limited depth of the trenches in TGs, the legs of the dead calves were visible above ground level (see Figures 2-5). We observed footsteps of herd members on both sides of the trench and over the soil covering the body, indicating a combined effort in burying the carcasses. While mounting the carcass, the elephant herd vocalized for 30-40 minutes, as the TG night security guards reported. All the cases had minute contextual differences and are mentioned below as four different case reports:
Case 1 belongs to Devpara TG, which falls in the jurisdiction of the Jalpaiguri division. The burial site’s location (26.829477° N, 89.009466° E) was 350 m away from the nearest human settlement and approximately 4 km from the nearest reserve forest. It rained the night of burial, making it easier for the herd (N=20) to mount the carcass. Loud vocalization from the herd was observed distantly. Large petechial haemorrhagic lesions and contusions were found in the dorsal surface of the entire vertebral region (Supplementary Appendix 1). As per long-term observation, the frequency of the elephant movement reduced by up to seventy percent. Elephants have rather started using parallel pathways and clearly avoid the previous path where the carcass was mounted. One of the parallel routes also witnessed a human death in quick succession after the calf mounting. However, such human death incidents could have resulted from other socio-ecological and circumstantial factors. Fresh elephant dung boli of different sizes were also observed near the mounted carcass. The locals worshipped the deceased calf before the forest department officials took it away.
Case 2 belongs to Chunabhati TG under the Binnaguri range of the Jalpaiguri division. The burial site (26.860416° N, 89.072500° E) was 150 m away from the nearest human settlement and 4.5 km from the nearest forest. Subcutaneous tissues were damaged, and wide haemorrhages were observed on the dorsal side of the body (Supplementary Appendix 2). It rained heavily on the night of the incident, and the soft soil layer facilitated an easier burial process. No vocalization was reported in this case. Elephant dung boli of various sizes present indirect evidence that the herd (N=15) also consisted of adults, sub-adults, and young adults. Although it’s challenging to identify the particular herd at night, but elephants clearly avoid the pathway of the mounted carcass. Now, they take alternate routes to the nearby forest after night grazing.
Case 3 corresponds to Bharnabari TG under the jurisdiction of the Hamiltonganj range of the Buxa tiger reserve (Supplementary Appendix 3). This burial site (26.764752° N, 89.361850° E) was 300 m from the nearest human settlement. The tea garden management and the villagers observed the unusually prolonged vocalization of an elephant herd (N=15 to 20) during their entire journey inside the TG. This vocalization involved both trumpets and roars. A fracture in the right hind limb was also observed. Long-term observation on this particular pathway reflected that elephants scarcely used this pathway, and the frequency hasn’t changed after the burial incident.
This TG was declared ’sick’ in 2008 as the company was at a loss and could not fully support the welfare of the tea garden residents. Moreover, the TG was shut down between 2005-08 due to loss and management failure. These socio-economic and political reasons contribute to comparatively less human density in this TG, thus, facilitating easier passage for the elephants. Footsteps of herd members were recorded around the mounting site, and it seemed that the herd had attempted to bury the deceased to ground level.
Case 4 belongs to Majherdabri TG under the jurisdiction of the East Damanpur range of the Buxa tiger reserve (Supplementary Appendix 4). The burial site’s location (26.544368° N, 89.557619° E) was around 500 m away from the nearest human settlement and close to the national highway. The ’partially buried’ carcass was observed by the TG workers, which postmortem examination by the forest department followed. As per the postmortem report, the calf died 60-72 hours before the examination. We concretely suggest that the elephant herd must have roamed for 40-45 hours before finding an appropriate trench to bury the carcass; otherwise, it would’ve been noticed by the TG labours previously.
Conversely, we also report a time lag between the time of death and burial and that the carcass was dragged to the appropriate point. This forest adjoining site allowed the elephants to access the trench and return to the forest. As the carcass was detected after almost three days, the kidneys were partially putrefied. Moreover, there were bruises and contusions on the dorsal side of the carcass – more than that in the other reported cases. Thus, it indicates that the herd carried the carcass through the trunk or the legs for a longer time.
The soil eruptions over the body of the carcass represent that rigor mortis has passed, and the gaseous components blow out of the soil before the carcass was detected. This phenomenon refers to ”postmortem flatulence” or colloquially ”burial explosion”. Rigor mortis among elephants arrive after twelve hours and remain for the next twelve hours.
Similar to other cases, this case was also peculiar as the elephant herd abandoned this active migratory route after mounting the deceased calf. They are reported to use different parallel paths after the incident.
Overall, we also observed contusions, mainly in the neck and dorsal parts along the vertebral column in all the cases. It was accompanied by hemorrhagic fluids in the trunks of most carcasses. Other observations reveal that the mucous membrane was pale and dry, and the tongue was soiled, congested, and inflamed in all cases. The average depth of the trenches was found to be 0.65 m. No body part was missing. Field observation from south Bengal shows carrying behaviour through the trunk and legs (Figure 6).