Conflict of interest
The authors declare that they have no conflict of interest.
No animal testing was performed during this study.
Sampling and field studies
All necessary authorization for the observational field study and securing of the area was obtained from the competent authorities. Photographs in Fig. 1 a and b were provided by Bridgid Wickham who has agreed to their inclusion in this publication.
The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.
SR conceived the research, wrote the manuscript, and conducted field observations. All authors conducted field observations and read and approved the final manuscript.