Indian Grey Hornbill bill grappling and aerial jousting

Raju Kasambe of Nagpur, India managed to photograph the bill grappling and aerial jousting of the Indian Grey Hornbill (Ocyceros birostris) in Nagpur, India. Raju has been studying this hornbill for the last three years but only on 20th March 2010 was he successful in obtaining good images.

The two hornbills indulged in such behaviour while perching on the same branch or on two nearby branches of a tree. They even bill-grapple when airborne, before landing on the branch of a tree. One male was seen tearing a short piece of branch from a tree it was perching on when confronting a nearby male.

Such behaviour has been described by Kemp (2001) as having “no obvious or immediate function.” It also includes mandibulating of sticks in the bill.

An earlier post describes the Malabar Pied Hornbills (Anthracoceros coronatus) indulging in locking bills between two males in northern Karnataka, India. Such play took place during flight to pre-roosting trees. Between different sexes, only gentle touching of bills was observed.

Over in Johor, Malaysia, interlocking of bills was reported in the Oriental Pied Hornbill (Anthracoceros albirostris).

Reference:
Kemp, A. C., 2001. Family Bucerotidae (Hornbills). In: del Hoyo, J., A. Elliott & J. Sargatal (eds.). Handbook of the birds of the world. Vol. 6. Mousebirds to Hornbills. Lynx Editions, Barcelona. Pp. 436-523.

Image by Raju Kasambe.